diff --git a/libc/arch-arm/generic/bionic/strlen.c b/libc/arch-arm/generic/bionic/strlen.c
index f6b9209..dccd564 100644
--- a/libc/arch-arm/generic/bionic/strlen.c
+++ b/libc/arch-arm/generic/bionic/strlen.c
@@ -67,53 +67,46 @@
         "sub     %[t], %[v], %[mask], lsr #7\n"
         "and     %[t], %[t], %[mask]        \n"
         "bics    %[t], %[t], %[v]           \n"
-        "it      eq                         \n"
-        "ldreq   %[v], [%[s]], #4           \n"
+        "bne     1f                         \n"
+        "ldr     %[v], [%[s]], #4           \n"
 #if !defined(__OPTIMIZE_SIZE__)
-        "bne     1f                         \n"
         "sub     %[t], %[v], %[mask], lsr #7\n"
         "and     %[t], %[t], %[mask]        \n"
         "bics    %[t], %[t], %[v]           \n"
-        "it      eq                         \n"
-        "ldreq   %[v], [%[s]], #4           \n"
         "bne     1f                         \n"
+        "ldr     %[v], [%[s]], #4           \n"
         "sub     %[t], %[v], %[mask], lsr #7\n"
         "and     %[t], %[t], %[mask]        \n"
         "bics    %[t], %[t], %[v]           \n"
-        "it      eq                         \n"
-        "ldreq   %[v], [%[s]], #4           \n"
         "bne     1f                         \n"
+        "ldr     %[v], [%[s]], #4           \n"
         "sub     %[t], %[v], %[mask], lsr #7\n"
         "and     %[t], %[t], %[mask]        \n"
         "bics    %[t], %[t], %[v]           \n"
-        "it      eq                         \n"
-        "ldreq   %[v], [%[s]], #4           \n"
         "bne     1f                         \n"
+        "ldr     %[v], [%[s]], #4           \n"
         "sub     %[t], %[v], %[mask], lsr #7\n"
         "and     %[t], %[t], %[mask]        \n"
         "bics    %[t], %[t], %[v]           \n"
-        "it      eq                         \n"
-        "ldreq   %[v], [%[s]], #4           \n"
         "bne     1f                         \n"
+        "ldr     %[v], [%[s]], #4           \n"
         "sub     %[t], %[v], %[mask], lsr #7\n"
         "and     %[t], %[t], %[mask]        \n"
         "bics    %[t], %[t], %[v]           \n"
-        "it      eq                         \n"
-        "ldreq   %[v], [%[s]], #4           \n"
         "bne     1f                         \n"
+        "ldr     %[v], [%[s]], #4           \n"
         "sub     %[t], %[v], %[mask], lsr #7\n"
         "and     %[t], %[t], %[mask]        \n"
         "bics    %[t], %[t], %[v]           \n"
-        "it      eq                         \n"
-        "ldreq   %[v], [%[s]], #4           \n"
         "bne     1f                         \n"
+        "ldr     %[v], [%[s]], #4           \n"
         "sub     %[t], %[v], %[mask], lsr #7\n"
         "and     %[t], %[t], %[mask]        \n"
         "bics    %[t], %[t], %[v]           \n"
-        "it      eq                         \n"
-        "ldreq   %[v], [%[s]], #4           \n"
+        "bne     1f                         \n"
+        "ldr     %[v], [%[s]], #4           \n"
 #endif
-        "beq     0b                         \n"
+        "b       0b                         \n"
         "1:                                 \n"
         "add     %[l], %[l], %[s]           \n"
         "tst     %[v], #0xFF                \n"
diff --git a/libc/bionic/pthread_create.cpp b/libc/bionic/pthread_create.cpp
index 9197aa3..9be86f1 100644
--- a/libc/bionic/pthread_create.cpp
+++ b/libc/bionic/pthread_create.cpp
@@ -278,7 +278,7 @@
       munmap(thread->attr.stack_base, thread->mmap_size);
     }
     async_safe_format_log(ANDROID_LOG_WARN, "libc", "pthread_create failed: clone failed: %s",
-                          strerror(errno));
+                          strerror(clone_errno));
     return clone_errno;
   }
 
diff --git a/libc/include/android/dlext.h b/libc/include/android/dlext.h
index ca3bd25..c824544 100644
--- a/libc/include/android/dlext.h
+++ b/libc/include/android/dlext.h
@@ -129,7 +129,7 @@
   struct android_namespace_t* library_namespace;
 } android_dlextinfo;
 
-void* android_dlopen_ext(const char* filename, int flag, const android_dlextinfo* extinfo)
+void* android_dlopen_ext(const char* __filename, int __flags, const android_dlextinfo* __info)
   __INTRODUCED_IN(21);
 
 __END_DECLS
diff --git a/libc/include/android/legacy_signal_inlines.h b/libc/include/android/legacy_signal_inlines.h
index 09db2a6..4d474b0 100644
--- a/libc/include/android/legacy_signal_inlines.h
+++ b/libc/include/android/legacy_signal_inlines.h
@@ -39,7 +39,7 @@
 
 #if __ANDROID_API__ < __ANDROID_API_L__
 
-sighandler_t bsd_signal(int signum, sighandler_t handler) __REMOVED_IN(21);
+sighandler_t bsd_signal(int __signal, sighandler_t __handler) __REMOVED_IN(21);
 
 /* These weren't introduced until L. */
 int __libc_current_sigrtmax() __attribute__((__weak__)) __VERSIONER_NO_GUARD;
diff --git a/libc/include/android/legacy_sys_stat_inlines.h b/libc/include/android/legacy_sys_stat_inlines.h
index 23a9f07..bbf54c0 100644
--- a/libc/include/android/legacy_sys_stat_inlines.h
+++ b/libc/include/android/legacy_sys_stat_inlines.h
@@ -36,8 +36,8 @@
 
 __BEGIN_DECLS
 
-static __inline int mkfifo(const char *__p, mode_t __m) {
-  return mknod(__p, (__m & ~S_IFMT) | S_IFIFO, (dev_t)0);
+static __inline int mkfifo(const char* __path, mode_t __mode) {
+  return mknod(__path, (__mode & ~S_IFMT) | S_IFIFO, (dev_t)0);
 }
 
 __END_DECLS
diff --git a/libc/include/android/set_abort_message.h b/libc/include/android/set_abort_message.h
index 18881a3..3dde673 100644
--- a/libc/include/android/set_abort_message.h
+++ b/libc/include/android/set_abort_message.h
@@ -33,7 +33,7 @@
 
 __BEGIN_DECLS
 
-void android_set_abort_message(const char* msg) __INTRODUCED_IN(21);
+void android_set_abort_message(const char* __msg) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/arpa/inet.h b/libc/include/arpa/inet.h
index d137130..db054c9 100644
--- a/libc/include/arpa/inet.h
+++ b/libc/include/arpa/inet.h
@@ -36,18 +36,18 @@
 
 __BEGIN_DECLS
 
-in_addr_t inet_addr(const char*);
-int inet_aton(const char*, struct in_addr*);
-in_addr_t inet_lnaof(struct in_addr) __INTRODUCED_IN(21);
-struct in_addr inet_makeaddr(in_addr_t, in_addr_t) __INTRODUCED_IN(21);
-in_addr_t inet_netof(struct in_addr) __INTRODUCED_IN(21);
-in_addr_t inet_network(const char*) __INTRODUCED_IN(21);
-char* inet_ntoa(struct in_addr);
-const char* inet_ntop(int, const void*, char*, socklen_t);
-unsigned int inet_nsap_addr(const char*, unsigned char*, int);
-char* inet_nsap_ntoa(int, const unsigned char*, char*);
-int inet_pton(int, const char*, void*);
+in_addr_t inet_addr(const char* __s);
+int inet_aton(const char* __s, struct in_addr* __addr);
+in_addr_t inet_lnaof(struct in_addr __addr) __INTRODUCED_IN(21);
+struct in_addr inet_makeaddr(in_addr_t __net, in_addr_t __host) __INTRODUCED_IN(21);
+in_addr_t inet_netof(struct in_addr __addr) __INTRODUCED_IN(21);
+in_addr_t inet_network(const char* __s) __INTRODUCED_IN(21);
+char* inet_ntoa(struct in_addr __addr);
+const char* inet_ntop(int __af, const void* __src, char* __dst, socklen_t __size);
+unsigned int inet_nsap_addr(const char* __ascii, unsigned char* __binary, int __n);
+char* inet_nsap_ntoa(int __binary_length, const unsigned char* __binary, char* __ascii);
+int inet_pton(int __af, const char* __src, void* __dst);
 
 __END_DECLS
 
-#endif /* _ARPA_INET_H_ */
+#endif
diff --git a/libc/include/assert.h b/libc/include/assert.h
index 8c456ef..7a9d84d 100644
--- a/libc/include/assert.h
+++ b/libc/include/assert.h
@@ -60,6 +60,6 @@
 #endif
 
 __BEGIN_DECLS
-void __assert(const char*, int, const char*) __noreturn;
-void __assert2(const char*, int, const char*, const char*) __noreturn;
+void __assert(const char* __file, int __line, const char* __msg) __noreturn;
+void __assert2(const char* __file, int __line, const char* __function, const char* __msg) __noreturn;
 __END_DECLS
diff --git a/libc/include/bits/fcntl.h b/libc/include/bits/fcntl.h
index 604d35a..e3b0e8c 100644
--- a/libc/include/bits/fcntl.h
+++ b/libc/include/bits/fcntl.h
@@ -33,7 +33,7 @@
 
 __BEGIN_DECLS
 
-int fcntl(int, int, ...);
+int fcntl(int __fd, int __cmd, ...);
 
 __END_DECLS
 
diff --git a/libc/include/bits/fortify/stdlib.h b/libc/include/bits/fortify/stdlib.h
index cf4b7ea..8f3b02c 100644
--- a/libc/include/bits/fortify/stdlib.h
+++ b/libc/include/bits/fortify/stdlib.h
@@ -40,7 +40,8 @@
 #if defined(__clang__)
 char* realpath(const char* path, char* resolved)
         __clang_error_if(__bos(resolved) != __BIONIC_FORTIFY_UNKNOWN_SIZE &&
-                         __bos(resolved) < __PATH_MAX, __realpath_buf_too_small_str);
+                         __bos(resolved) < __PATH_MAX, __realpath_buf_too_small_str)
+        __clang_error_if(!path, "'realpath': NULL path is never correct; flipped arguments?");
 /* No need for a definition; the only issues we can catch are at compile-time. */
 
 #else /* defined(__clang__) */
diff --git a/libc/include/bits/getopt.h b/libc/include/bits/getopt.h
index 7153d48..5481449 100644
--- a/libc/include/bits/getopt.h
+++ b/libc/include/bits/getopt.h
@@ -33,9 +33,9 @@
 
 __BEGIN_DECLS
 
-int	 getopt(int, char * const [], const char *);
+int getopt(int __argc, char* const __argv[], const char* __options);
 
-extern char *optarg;			/* getopt(3) external variables */
+extern char* optarg;
 extern int optind, opterr, optopt;
 
 __END_DECLS
diff --git a/libc/include/bits/ioctl.h b/libc/include/bits/ioctl.h
index 53116ca..0cf87d2 100644
--- a/libc/include/bits/ioctl.h
+++ b/libc/include/bits/ioctl.h
@@ -33,7 +33,7 @@
 
 __BEGIN_DECLS
 
-int ioctl(int, int, ...);
+int ioctl(int __fd, int __request, ...);
 
 __END_DECLS
 
diff --git a/libc/include/bits/lockf.h b/libc/include/bits/lockf.h
index a8e273e..929c68c 100644
--- a/libc/include/bits/lockf.h
+++ b/libc/include/bits/lockf.h
@@ -39,8 +39,8 @@
 
 __BEGIN_DECLS
 
-int lockf(int, int, off_t) __RENAME_IF_FILE_OFFSET64(lockf64) __INTRODUCED_IN(24);
-int lockf64(int, int, off64_t) __INTRODUCED_IN(24);
+int lockf(int __fd, int __cmd, off_t __length) __RENAME_IF_FILE_OFFSET64(lockf64) __INTRODUCED_IN(24);
+int lockf64(int __fd, int __cmd, off64_t __length) __INTRODUCED_IN(24);
 
 __END_DECLS
 
diff --git a/libc/include/bits/strcasecmp.h b/libc/include/bits/strcasecmp.h
index df1a6b8..594046a 100644
--- a/libc/include/bits/strcasecmp.h
+++ b/libc/include/bits/strcasecmp.h
@@ -35,10 +35,10 @@
 
 __BEGIN_DECLS
 
-int strcasecmp(const char*, const char*) __attribute_pure__;
-int strcasecmp_l(const char*, const char*, locale_t) __attribute_pure__ __INTRODUCED_IN(23);
-int strncasecmp(const char*, const char*, size_t) __attribute_pure__;
-int strncasecmp_l(const char*, const char*, size_t, locale_t) __attribute_pure__ __INTRODUCED_IN(23);
+int strcasecmp(const char* __s1, const char* __s2) __attribute_pure__;
+int strcasecmp_l(const char* __s1, const char* __s2, locale_t __l) __attribute_pure__ __INTRODUCED_IN(23);
+int strncasecmp(const char* __s1, const char* __s2, size_t __n) __attribute_pure__;
+int strncasecmp_l(const char* __s1, const char* __s2, size_t __n, locale_t __l) __attribute_pure__ __INTRODUCED_IN(23);
 
 __END_DECLS
 
diff --git a/libc/include/bits/wctype.h b/libc/include/bits/wctype.h
index f21d46e..a51eca2 100644
--- a/libc/include/bits/wctype.h
+++ b/libc/include/bits/wctype.h
@@ -37,29 +37,29 @@
 
 #define WEOF __BIONIC_CAST(static_cast, wint_t, -1)
 
-int iswalnum(wint_t);
-int iswalpha(wint_t);
-int iswblank(wint_t) __INTRODUCED_IN(21);
-int iswcntrl(wint_t);
-int iswdigit(wint_t);
-int iswgraph(wint_t);
-int iswlower(wint_t);
-int iswprint(wint_t);
-int iswpunct(wint_t);
-int iswspace(wint_t);
-int iswupper(wint_t);
-int iswxdigit(wint_t);
+int iswalnum(wint_t __wc);
+int iswalpha(wint_t __wc);
+int iswblank(wint_t __wc) __INTRODUCED_IN(21);
+int iswcntrl(wint_t __wc);
+int iswdigit(wint_t __wc);
+int iswgraph(wint_t __wc);
+int iswlower(wint_t __wc);
+int iswprint(wint_t __wc);
+int iswpunct(wint_t __wc);
+int iswspace(wint_t __wc);
+int iswupper(wint_t __wc);
+int iswxdigit(wint_t __wc);
 
-wint_t towlower(wint_t);
-wint_t towupper(wint_t);
+wint_t towlower(wint_t __wc);
+wint_t towupper(wint_t __wc);
 
 typedef long wctype_t;
-wctype_t wctype(const char*);
-int iswctype(wint_t, wctype_t);
+wctype_t wctype(const char* __name);
+int iswctype(wint_t __wc, wctype_t __type);
 
 typedef const void* wctrans_t;
-wint_t towctrans(wint_t, wctrans_t) __INTRODUCED_IN(26) __VERSIONER_NO_GUARD;
-wctrans_t wctrans(const char*) __INTRODUCED_IN(26) __VERSIONER_NO_GUARD;
+wint_t towctrans(wint_t __wc, wctrans_t __transform) __INTRODUCED_IN(26) __VERSIONER_NO_GUARD;
+wctrans_t wctrans(const char* __name) __INTRODUCED_IN(26) __VERSIONER_NO_GUARD;
 
 __END_DECLS
 
diff --git a/libc/include/ctype.h b/libc/include/ctype.h
index 84dd5aa..df11cb1 100644
--- a/libc/include/ctype.h
+++ b/libc/include/ctype.h
@@ -61,45 +61,45 @@
 
 extern const char* _ctype_;
 
-int isalnum(int);
-int isalpha(int);
-int isblank(int);
-int iscntrl(int);
-int isdigit(int);
-int isgraph(int);
-int islower(int);
-int isprint(int);
-int ispunct(int);
-int isspace(int);
-int isupper(int);
-int isxdigit(int);
-int tolower(int);
-int toupper(int);
+int isalnum(int __ch);
+int isalpha(int __ch);
+int isblank(int __ch);
+int iscntrl(int __ch);
+int isdigit(int __ch);
+int isgraph(int __ch);
+int islower(int __ch);
+int isprint(int __ch);
+int ispunct(int __ch);
+int isspace(int __ch);
+int isupper(int __ch);
+int isxdigit(int __ch);
+int tolower(int __ch);
+int toupper(int __ch);
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
-int isalnum_l(int, locale_t) __INTRODUCED_IN(21);
-int isalpha_l(int, locale_t) __INTRODUCED_IN(21);
-int isblank_l(int, locale_t) __INTRODUCED_IN(21);
-int iscntrl_l(int, locale_t) __INTRODUCED_IN(21);
-int isdigit_l(int, locale_t) __INTRODUCED_IN(21);
-int isgraph_l(int, locale_t) __INTRODUCED_IN(21);
-int islower_l(int, locale_t) __INTRODUCED_IN(21);
-int isprint_l(int, locale_t) __INTRODUCED_IN(21);
-int ispunct_l(int, locale_t) __INTRODUCED_IN(21);
-int isspace_l(int, locale_t) __INTRODUCED_IN(21);
-int isupper_l(int, locale_t) __INTRODUCED_IN(21);
-int isxdigit_l(int, locale_t) __INTRODUCED_IN(21);
-int tolower_l(int, locale_t) __INTRODUCED_IN(21);
-int toupper_l(int, locale_t) __INTRODUCED_IN(21);
+int isalnum_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int isalpha_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int isblank_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int iscntrl_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int isdigit_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int isgraph_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int islower_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int isprint_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int ispunct_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int isspace_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int isupper_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int isxdigit_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int tolower_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
+int toupper_l(int __ch, locale_t __l) __INTRODUCED_IN(21);
 #else
 // Implemented as static inlines before 21.
 #endif
 
-int isascii(int);
-int toascii(int);
-int _tolower(int) __INTRODUCED_IN(21);
-int _toupper(int) __INTRODUCED_IN(21);
+int isascii(int __ch);
+int toascii(int __ch);
+int _tolower(int __ch) __INTRODUCED_IN(21);
+int _toupper(int __ch) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif /* !_CTYPE_H_ */
+#endif
diff --git a/libc/include/dirent.h b/libc/include/dirent.h
index ebcf085..7ac4ab7 100644
--- a/libc/include/dirent.h
+++ b/libc/include/dirent.h
@@ -76,30 +76,27 @@
 
 typedef struct DIR DIR;
 
-DIR* opendir(const char*);
-DIR* fdopendir(int);
-struct dirent* readdir(DIR*);
-struct dirent64* readdir64(DIR*) __INTRODUCED_IN(21);
-int readdir_r(DIR*, struct dirent*, struct dirent**);
-int readdir64_r(DIR*, struct dirent64*, struct dirent64**) __INTRODUCED_IN(21);
-int closedir(DIR*);
-void rewinddir(DIR*);
-void seekdir(DIR*, long) __INTRODUCED_IN(23);
-long telldir(DIR*) __INTRODUCED_IN(23);
-int dirfd(DIR*);
-int alphasort(const struct dirent**, const struct dirent**);
-int alphasort64(const struct dirent64**, const struct dirent64**) __INTRODUCED_IN(21);
-int scandir64(const char*, struct dirent64***, int (*)(const struct dirent64*),
-              int (*)(const struct dirent64**, const struct dirent64**)) __INTRODUCED_IN(21);
-int scandir(const char*, struct dirent***, int (*)(const struct dirent*), int (*)(const struct dirent**, const struct dirent**));
+DIR* opendir(const char* __path);
+DIR* fdopendir(int __dir_fd);
+struct dirent* readdir(DIR* __dir);
+struct dirent64* readdir64(DIR* __dir) __INTRODUCED_IN(21);
+int readdir_r(DIR* __dir, struct dirent* __entry, struct dirent** __buffer);
+int readdir64_r(DIR* __dir, struct dirent64* __entry, struct dirent64** __buffer) __INTRODUCED_IN(21);
+int closedir(DIR* __dir);
+void rewinddir(DIR* __dir);
+void seekdir(DIR* __dir, long __location) __INTRODUCED_IN(23);
+long telldir(DIR* __dir) __INTRODUCED_IN(23);
+int dirfd(DIR* __dir);
+int alphasort(const struct dirent** __lhs, const struct dirent** __rhs);
+int alphasort64(const struct dirent64** __lhs, const struct dirent64** __rhs) __INTRODUCED_IN(21);
+int scandir64(const char* __path, struct dirent64*** __name_list, int (*__filter)(const struct dirent64*), int (*__comparator)(const struct dirent64**, const struct dirent64**)) __INTRODUCED_IN(21);
+int scandir(const char* __path, struct dirent*** __name_list, int (*__filter)(const struct dirent*), int (*__comparator)(const struct dirent**, const struct dirent**));
 
 #if defined(__USE_GNU)
-int scandirat64(int, const char*, struct dirent64***, int (*)(const struct dirent64*),
-                int (*)(const struct dirent64**, const struct dirent64**)) __INTRODUCED_IN(24);
-int scandirat(int, const char*, struct dirent***, int (*)(const struct dirent*),
-              int (*)(const struct dirent**, const struct dirent**)) __INTRODUCED_IN(24);
+int scandirat64(int __dir_fd, const char* __path, struct dirent64*** __name_list, int (*__filter)(const struct dirent64*), int (*__comparator)(const struct dirent64**, const struct dirent64**)) __INTRODUCED_IN(24);
+int scandirat(int __dir_fd, const char* __path, struct dirent*** __name_list, int (*__filter)(const struct dirent*), int (*__comparator)(const struct dirent**, const struct dirent**)) __INTRODUCED_IN(24);
 #endif
 
 __END_DECLS
 
-#endif /* _DIRENT_H_ */
+#endif
diff --git a/libc/include/dlfcn.h b/libc/include/dlfcn.h
index 76bbdb8..68d8bc9 100644
--- a/libc/include/dlfcn.h
+++ b/libc/include/dlfcn.h
@@ -45,12 +45,12 @@
   void* dli_saddr;
 } Dl_info;
 
-void* dlopen(const char* filename, int flag);
-int dlclose(void* handle);
+void* dlopen(const char* __filename, int __flag);
+int dlclose(void* __handle);
 char* dlerror(void);
-void* dlsym(void* handle, const char* symbol);
-void* dlvsym(void* handle, const char* symbol, const char* version) __INTRODUCED_IN(24);
-int dladdr(const void* addr, Dl_info* info);
+void* dlsym(void* __handle, const char* __symbol);
+void* dlvsym(void* __handle, const char* __symbol, const char* __version) __INTRODUCED_IN(24);
+int dladdr(const void* __addr, Dl_info* __info);
 
 #define RTLD_LOCAL    0
 #define RTLD_LAZY     0x00001
@@ -77,4 +77,4 @@
 
 __END_DECLS
 
-#endif /* __DLFCN_H */
+#endif
diff --git a/libc/include/err.h b/libc/include/err.h
index 7ee3608..a64d01d 100644
--- a/libc/include/err.h
+++ b/libc/include/err.h
@@ -41,18 +41,14 @@
 
 __BEGIN_DECLS
 
-/* printf's format string isn't nullable; the err family's one is,
- * so we can't use __errlike here. */
-#define __errlike(x, y) __attribute__((__format__(printf, x, y)))
-
-__noreturn void err(int, const char *, ...) __errlike(2, 3);
-__noreturn void verr(int, const char *, va_list) __errlike(2, 0);
-__noreturn void errx(int, const char *, ...) __errlike(2, 3);
-__noreturn void verrx(int, const char *, va_list) __errlike(2, 0);
-void warn(const char *, ...) __errlike(1, 2);
-void vwarn(const char *, va_list) __errlike(1, 0);
-void warnx(const char *, ...) __errlike(1, 2);
-void vwarnx(const char *, va_list) __errlike(1, 0);
+__noreturn void err(int __status, const char* __fmt, ...) __printflike(2, 3);
+__noreturn void verr(int __status, const char* __fmt, va_list __args) __printflike(2, 0);
+__noreturn void errx(int __status, const char* __fmt, ...) __printflike(2, 3);
+__noreturn void verrx(int __status, const char* __fmt, va_list __args) __printflike(2, 0);
+void warn(const char* __fmt, ...) __printflike(1, 2);
+void vwarn(const char* __fmt, va_list __args) __printflike(1, 0);
+void warnx(const char* __fmt, ...) __printflike(1, 2);
+void vwarnx(const char* __fmt, va_list __args) __printflike(1, 0);
 
 __END_DECLS
 
diff --git a/libc/include/error.h b/libc/include/error.h
index b145afc..d612994 100644
--- a/libc/include/error.h
+++ b/libc/include/error.h
@@ -37,8 +37,8 @@
 extern unsigned int error_message_count __INTRODUCED_IN(23);
 extern int error_one_per_line __INTRODUCED_IN(23);
 
-void error(int, int, const char*, ...) __printflike(3, 4) __INTRODUCED_IN(23);
-void error_at_line(int, int, const char*, unsigned int, const char*, ...)
+void error(int __status, int __errno, const char* __fmt, ...) __printflike(3, 4) __INTRODUCED_IN(23);
+void error_at_line(int __status, int __errno, const char* __filename, unsigned int __line_number, const char* __fmt, ...)
     __printflike(5, 6) __INTRODUCED_IN(23);
 
 __END_DECLS
diff --git a/libc/include/fcntl.h b/libc/include/fcntl.h
index cd52b45..4852f5f 100644
--- a/libc/include/fcntl.h
+++ b/libc/include/fcntl.h
@@ -69,26 +69,26 @@
 #define SYNC_FILE_RANGE_WAIT_AFTER 4
 #endif
 
-int creat(const char*, mode_t);
-int creat64(const char*, mode_t) __INTRODUCED_IN(21);
-int openat(int, const char*, int, ...) __overloadable __RENAME_CLANG(openat);
-int openat64(int, const char*, int, ...) __INTRODUCED_IN(21);
-int open(const char*, int, ...) __overloadable __RENAME_CLANG(open);
-int open64(const char*, int, ...) __INTRODUCED_IN(21);
-ssize_t splice(int, off64_t*, int, off64_t*, size_t, unsigned int) __INTRODUCED_IN(21);
-ssize_t tee(int, int, size_t, unsigned int) __INTRODUCED_IN(21);
-ssize_t vmsplice(int, const struct iovec*, size_t, unsigned int) __INTRODUCED_IN(21);
+int creat(const char* __path, mode_t __mode);
+int creat64(const char* __path, mode_t __mode) __INTRODUCED_IN(21);
+int openat(int __dir_fd, const char* __path, int __flags, ...) __overloadable __RENAME_CLANG(openat);
+int openat64(int __dir_fd, const char* __path, int __flags, ...) __INTRODUCED_IN(21);
+int open(const char* __path, int __flags, ...) __overloadable __RENAME_CLANG(open);
+int open64(const char* __path, int __flags, ...) __INTRODUCED_IN(21);
+ssize_t splice(int __in_fd, off64_t* __in_offset, int __out_fd, off64_t* __out_offset, size_t __length, unsigned int __flags) __INTRODUCED_IN(21);
+ssize_t tee(int __in_fd, int __out_fd, size_t __length, unsigned int __flags) __INTRODUCED_IN(21);
+ssize_t vmsplice(int __fd, const struct iovec* __iov, size_t __count, unsigned int __flags) __INTRODUCED_IN(21);
 
-int fallocate(int, int, off_t, off_t) __RENAME_IF_FILE_OFFSET64(fallocate64) __INTRODUCED_IN(21);
-int fallocate64(int, int, off64_t, off64_t) __INTRODUCED_IN(21);
-int posix_fadvise(int, off_t, off_t, int) __RENAME_IF_FILE_OFFSET64(posix_fadvise64) __INTRODUCED_IN(21);
-int posix_fadvise64(int, off64_t, off64_t, int) __INTRODUCED_IN(21);
-int posix_fallocate(int, off_t, off_t) __RENAME_IF_FILE_OFFSET64(posix_fallocate64) __INTRODUCED_IN(21);
-int posix_fallocate64(int, off64_t, off64_t) __INTRODUCED_IN(21);
+int fallocate(int __fd, int __mode, off_t __offset, off_t __length) __RENAME_IF_FILE_OFFSET64(fallocate64) __INTRODUCED_IN(21);
+int fallocate64(int __fd, int __mode, off64_t __offset, off64_t __length) __INTRODUCED_IN(21);
+int posix_fadvise(int __fd, off_t __offset, off_t __length, int __advice) __RENAME_IF_FILE_OFFSET64(posix_fadvise64) __INTRODUCED_IN(21);
+int posix_fadvise64(int __fd, off64_t __offset, off64_t __length, int __advice) __INTRODUCED_IN(21);
+int posix_fallocate(int __fd, off_t __offset, off_t __length) __RENAME_IF_FILE_OFFSET64(posix_fallocate64) __INTRODUCED_IN(21);
+int posix_fallocate64(int __fd, off64_t __offset, off64_t __length) __INTRODUCED_IN(21);
 
 #if defined(__USE_GNU)
-ssize_t readahead(int, off64_t, size_t) __INTRODUCED_IN(16);
-int sync_file_range(int, off64_t, off64_t, unsigned int) __INTRODUCED_IN(26);
+ssize_t readahead(int __fd, off64_t __offset, size_t __length) __INTRODUCED_IN(16);
+int sync_file_range(int __fd, off64_t __offset, off64_t __length, unsigned int __flags) __INTRODUCED_IN(26);
 #endif
 
 #if defined(__BIONIC_INCLUDE_FORTIFY_HEADERS)
@@ -97,4 +97,4 @@
 
 __END_DECLS
 
-#endif /* _FCNTL_H */
+#endif
diff --git a/libc/include/fnmatch.h b/libc/include/fnmatch.h
index 1a5348b..3fcc665 100644
--- a/libc/include/fnmatch.h
+++ b/libc/include/fnmatch.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _FNMATCH_H
 #define _FNMATCH_H
 
@@ -44,8 +45,8 @@
 #define FNM_IGNORECASE   FNM_CASEFOLD
 #define FNM_FILE_NAME    FNM_PATHNAME
 
-int fnmatch(const char* pattern, const char* string, int flags);
+int fnmatch(const char* __pattern, const char* __string, int __flags);
 
 __END_DECLS
 
-#endif /* _FNMATCH_H */
+#endif
diff --git a/libc/include/fts.h b/libc/include/fts.h
index b46c19c..3649d3a 100644
--- a/libc/include/fts.h
+++ b/libc/include/fts.h
@@ -115,12 +115,13 @@
 } FTSENT;
 
 __BEGIN_DECLS
-FTSENT	*fts_children(FTS *, int);
-int	 fts_close(FTS *);
-FTS	*fts_open(char * const *, int,
-	    int (*)(const FTSENT **, const FTSENT **));
-FTSENT	*fts_read(FTS *);
-int	 fts_set(FTS *, FTSENT *, int);
+
+FTSENT* fts_children(FTS* __fts, int __options);
+int fts_close(FTS* __fts);
+FTS* fts_open(char* const* __path, int __options, int (*__comparator)(const FTSENT** __lhs, const FTSENT** __rhs));
+FTSENT* fts_read(FTS* __fts);
+int fts_set(FTS* __fts, FTSENT* __entry, int __options);
+
 __END_DECLS
 
 #endif /* !_FTS_H_ */
diff --git a/libc/include/ftw.h b/libc/include/ftw.h
index cb8ae7d..300f624 100644
--- a/libc/include/ftw.h
+++ b/libc/include/ftw.h
@@ -55,12 +55,12 @@
 };
 
 __BEGIN_DECLS
-int ftw(const char*, int (*)(const char*, const struct stat*, int), int) __INTRODUCED_IN(17);
-int nftw(const char*, int (*)(const char*, const struct stat*, int, struct FTW*), int, int)
+int ftw(const char* __dir_path, int (*__callback)(const char*, const struct stat*, int), int __max_fd_count) __INTRODUCED_IN(17);
+int nftw(const char* __dir_path, int (*__callback)(const char*, const struct stat*, int, struct FTW*), int __max_fd_count, int __flags)
   __INTRODUCED_IN(17);
-int ftw64(const char*, int (*)(const char*, const struct stat64*, int), int) __INTRODUCED_IN(21);
-int nftw64(const char*, int (*)(const char*, const struct stat64*, int, struct FTW*), int, int)
+int ftw64(const char* __dir_path, int (*__callback)(const char*, const struct stat64*, int), int __max_fd_count) __INTRODUCED_IN(21);
+int nftw64(const char* __dir_path, int (*__callback)(const char*, const struct stat64*, int, struct FTW*), int __max_fd_count, int __flags)
   __INTRODUCED_IN(21);
 __END_DECLS
 
-#endif	/* !_FTW_H */
+#endif
diff --git a/libc/include/getopt.h b/libc/include/getopt.h
index 46d2eb7..c5a6106 100644
--- a/libc/include/getopt.h
+++ b/libc/include/getopt.h
@@ -59,10 +59,8 @@
 };
 
 __BEGIN_DECLS
-int	getopt_long(int, char * const *, const char *,
-	const struct option *, int *);
-int	getopt_long_only(int, char * const *, const char *,
-	const struct option *, int *);
+int getopt_long(int __argc, char* const* __argv, const char* __options, const struct option* __long_options, int* __long_index);
+int getopt_long_only(int __argc, char* const* __argv, const char* __options, const struct option* __long_options, int* __long_index);
 
 #ifndef _OPTRESET_DECLARED
 #define	_OPTRESET_DECLARED
@@ -70,4 +68,4 @@
 #endif
 __END_DECLS
  
-#endif /* !_GETOPT_H_ */
+#endif
diff --git a/libc/include/grp.h b/libc/include/grp.h
index b727562..9d67adf 100644
--- a/libc/include/grp.h
+++ b/libc/include/grp.h
@@ -47,19 +47,19 @@
 
 __BEGIN_DECLS
 
-struct group* getgrgid(gid_t);
-struct group* getgrnam(const char*);
+struct group* getgrgid(gid_t __gid);
+struct group* getgrnam(const char* __name);
 
 /* Note: Android has thousands and thousands of ids to iterate through. */
 struct group* getgrent(void) __INTRODUCED_IN(26);
 
 void setgrent(void) __INTRODUCED_IN(26);
 void endgrent(void) __INTRODUCED_IN(26);
-int getgrgid_r(gid_t, struct group*, char*, size_t, struct group**) __INTRODUCED_IN(24);
-int getgrnam_r(const char*, struct group*, char*, size_t, struct group**) __INTRODUCED_IN(24);
-int getgrouplist (const char*, gid_t, gid_t*, int*);
-int initgroups (const char*, gid_t);
+int getgrgid_r(gid_t __gid, struct group* __group, char* __buf, size_t __n, struct group** __result) __INTRODUCED_IN(24);
+int getgrnam_r(const char* __name, struct group* __group, char* __buf, size_t __n, struct group** __result) __INTRODUCED_IN(24);
+int getgrouplist(const char* __user, gid_t __group, gid_t* __groups, int* __group_count);
+int initgroups(const char* __user, gid_t __group);
 
 __END_DECLS
 
-#endif /* !_GRP_H_ */
+#endif
diff --git a/libc/include/ifaddrs.h b/libc/include/ifaddrs.h
index 083b27a..0e2b0ea 100644
--- a/libc/include/ifaddrs.h
+++ b/libc/include/ifaddrs.h
@@ -51,8 +51,8 @@
 #define ifa_broadaddr ifa_ifu.ifu_broadaddr
 #define ifa_dstaddr ifa_ifu.ifu_dstaddr
 
-void freeifaddrs(struct ifaddrs*) __INTRODUCED_IN(24);
-int getifaddrs(struct ifaddrs**) __INTRODUCED_IN(24);
+void freeifaddrs(struct ifaddrs* __ptr) __INTRODUCED_IN(24);
+int getifaddrs(struct ifaddrs** __list_ptr) __INTRODUCED_IN(24);
 
 __END_DECLS
 
diff --git a/libc/include/inttypes.h b/libc/include/inttypes.h
index 43474df..7a409d8 100644
--- a/libc/include/inttypes.h
+++ b/libc/include/inttypes.h
@@ -255,12 +255,12 @@
 } imaxdiv_t;
 
 __BEGIN_DECLS
-intmax_t imaxabs(intmax_t) __attribute_const__ __INTRODUCED_IN(19);
-imaxdiv_t imaxdiv(intmax_t, intmax_t) __attribute_const__ __INTRODUCED_IN(19);
-intmax_t strtoimax(const char*, char**, int);
-uintmax_t strtoumax(const char*, char**, int);
-intmax_t wcstoimax(const wchar_t*, wchar_t**, int) __INTRODUCED_IN(21);
-uintmax_t wcstoumax(const wchar_t*, wchar_t**, int) __INTRODUCED_IN(21);
+intmax_t imaxabs(intmax_t __i) __attribute_const__ __INTRODUCED_IN(19);
+imaxdiv_t imaxdiv(intmax_t __numerator, intmax_t __denominator) __attribute_const__ __INTRODUCED_IN(19);
+intmax_t strtoimax(const char* __s, char** __end_ptr, int __base);
+uintmax_t strtoumax(const char* __s, char** __end_ptr, int __base);
+intmax_t wcstoimax(const wchar_t* __s, wchar_t** __end_ptr, int __base) __INTRODUCED_IN(21);
+uintmax_t wcstoumax(const wchar_t* __s, wchar_t** __end_ptr, int __base) __INTRODUCED_IN(21);
 __END_DECLS
 
-#endif /* _INTTYPES_H_ */
+#endif
diff --git a/libc/include/langinfo.h b/libc/include/langinfo.h
index c330117..d9d8c15 100644
--- a/libc/include/langinfo.h
+++ b/libc/include/langinfo.h
@@ -92,8 +92,8 @@
 #define NOEXPR 54
 #define CRNCYSTR 55
 
-char* nl_langinfo(nl_item) __INTRODUCED_IN(26);
-char* nl_langinfo_l(nl_item, locale_t) __INTRODUCED_IN(26);
+char* nl_langinfo(nl_item __item) __INTRODUCED_IN(26);
+char* nl_langinfo_l(nl_item __item, locale_t __l) __INTRODUCED_IN(26);
 
 __END_DECLS
 
diff --git a/libc/include/libgen.h b/libc/include/libgen.h
index f864ee1..5fa9089 100644
--- a/libc/include/libgen.h
+++ b/libc/include/libgen.h
@@ -32,7 +32,6 @@
 #include <sys/cdefs.h>
 #include <sys/types.h>
 
-
 __BEGIN_DECLS
 
 /*
@@ -42,19 +41,19 @@
  * Note that this has the wrong argument cv-qualifiers, but doesn't modify its
  * input and uses thread-local storage for the result if necessary.
  */
-char* __posix_basename(const char*) __RENAME(basename);
+char* __posix_basename(const char* __path) __RENAME(basename);
 
 #define basename __posix_basename
 
 /* This has the wrong argument cv-qualifiers, but doesn't modify its input and uses thread-local storage for the result if necessary. */
-char* dirname(const char*);
+char* dirname(const char* __path);
 
 #if !defined(__LP64__)
 /* These non-standard functions are not needed on Android; basename and dirname use thread-local storage. */
-int dirname_r(const char*, char*, size_t);
-int basename_r(const char*, char*, size_t);
+int dirname_r(const char* __path, char* __buf, size_t __n);
+int basename_r(const char* __path, char* __buf, size_t __n);
 #endif
 
 __END_DECLS
 
-#endif /* _LIBGEN_H */
+#endif
diff --git a/libc/include/link.h b/libc/include/link.h
index dd3b99f..072f093 100644
--- a/libc/include/link.h
+++ b/libc/include/link.h
@@ -50,9 +50,9 @@
 };
 
 #if defined(__arm__)
-int dl_iterate_phdr(int (*)(struct dl_phdr_info*, size_t, void*), void*) __INTRODUCED_IN(21);
+int dl_iterate_phdr(int (*__callback)(struct dl_phdr_info*, size_t, void*), void* __data) __INTRODUCED_IN(21);
 #else
-int dl_iterate_phdr(int (*)(struct dl_phdr_info*, size_t, void*), void*);
+int dl_iterate_phdr(int (*__callback)(struct dl_phdr_info*, size_t, void*), void* __data);
 #endif
 
 #ifdef __arm__
@@ -84,4 +84,4 @@
 
 __END_DECLS
 
-#endif /* _LINK_H_ */
+#endif
diff --git a/libc/include/locale.h b/libc/include/locale.h
index c1b6299..4290992 100644
--- a/libc/include/locale.h
+++ b/libc/include/locale.h
@@ -98,14 +98,14 @@
 
 struct lconv* localeconv(void) __INTRODUCED_IN(21) __VERSIONER_NO_GUARD;
 
-locale_t duplocale(locale_t) __INTRODUCED_IN(21);
-void freelocale(locale_t) __INTRODUCED_IN(21);
-locale_t newlocale(int, const char*, locale_t) __INTRODUCED_IN(21);
-char* setlocale(int, const char*);
-locale_t uselocale(locale_t) __INTRODUCED_IN(21);
+locale_t duplocale(locale_t __l) __INTRODUCED_IN(21);
+void freelocale(locale_t __l) __INTRODUCED_IN(21);
+locale_t newlocale(int __category_mask, const char* __locale_name, locale_t __base) __INTRODUCED_IN(21);
+char* setlocale(int __category, const char* __locale_name);
+locale_t uselocale(locale_t __l) __INTRODUCED_IN(21);
 
 #define LC_GLOBAL_LOCALE __BIONIC_CAST(reinterpret_cast, locale_t, -1L)
 
 __END_DECLS
 
-#endif /* _LOCALE_H_ */
+#endif
diff --git a/libc/include/malloc.h b/libc/include/malloc.h
index db5da04..80b08f6 100644
--- a/libc/include/malloc.h
+++ b/libc/include/malloc.h
@@ -30,13 +30,13 @@
 #define __BIONIC_ALLOC_SIZE(...) __attribute__((__alloc_size__(__VA_ARGS__)))
 #endif
 
-void* malloc(size_t byte_count) __mallocfunc __BIONIC_ALLOC_SIZE(1) __wur;
-void* calloc(size_t item_count, size_t item_size) __mallocfunc __BIONIC_ALLOC_SIZE(1,2) __wur;
-void* realloc(void* p, size_t byte_count) __BIONIC_ALLOC_SIZE(2) __wur;
-void free(void* p);
+void* malloc(size_t __byte_count) __mallocfunc __BIONIC_ALLOC_SIZE(1) __wur;
+void* calloc(size_t __item_count, size_t __item_size) __mallocfunc __BIONIC_ALLOC_SIZE(1,2) __wur;
+void* realloc(void* __ptr, size_t __byte_count) __BIONIC_ALLOC_SIZE(2) __wur;
+void free(void* __ptr);
 
-void* memalign(size_t alignment, size_t byte_count) __mallocfunc __BIONIC_ALLOC_SIZE(2) __wur;
-size_t malloc_usable_size(const void* p) __INTRODUCED_IN(17);
+void* memalign(size_t __alignment, size_t __byte_count) __mallocfunc __BIONIC_ALLOC_SIZE(2) __wur;
+size_t malloc_usable_size(const void* __ptr) __INTRODUCED_IN(17);
 
 #ifndef STRUCT_MALLINFO_DECLARED
 #define STRUCT_MALLINFO_DECLARED 1
@@ -75,12 +75,11 @@
  *   <!-- more heaps -->
  * </malloc>
  */
-int malloc_info(int, FILE*) __INTRODUCED_IN(23);
+int malloc_info(int __must_be_zero, FILE* __fp) __INTRODUCED_IN(23);
 
 /* mallopt options */
 #define M_DECAY_TIME -100
-
-int mallopt(int, int) __INTRODUCED_IN(26);
+int mallopt(int __option, int __value) __INTRODUCED_IN(26);
 
 __END_DECLS
 
diff --git a/libc/include/mntent.h b/libc/include/mntent.h
index 551a085..d5987dc 100644
--- a/libc/include/mntent.h
+++ b/libc/include/mntent.h
@@ -57,11 +57,11 @@
 
 __BEGIN_DECLS
 
-int endmntent(FILE*) __INTRODUCED_IN(21);
-struct mntent* getmntent(FILE*);
-struct mntent* getmntent_r(FILE*, struct mntent*, char*, int) __INTRODUCED_IN(21);
-FILE* setmntent(const char*, const char*) __INTRODUCED_IN(21);
-char* hasmntopt(const struct mntent*, const char*) __INTRODUCED_IN(26);
+int endmntent(FILE* __fp) __INTRODUCED_IN(21);
+struct mntent* getmntent(FILE* __fp);
+struct mntent* getmntent_r(FILE* __fp, struct mntent* __entry, char* __buf, int __size) __INTRODUCED_IN(21);
+FILE* setmntent(const char* __filename, const char* __type) __INTRODUCED_IN(21);
+char* hasmntopt(const struct mntent* __entry, const char* __option) __INTRODUCED_IN(26);
 
 __END_DECLS
 
diff --git a/libc/include/net/if.h b/libc/include/net/if.h
index eac7699..f261f71 100644
--- a/libc/include/net/if.h
+++ b/libc/include/net/if.h
@@ -44,10 +44,10 @@
   char* if_name;
 };
 
-char* if_indextoname(unsigned, char*);
-unsigned if_nametoindex(const char*);
+char* if_indextoname(unsigned __index, char* __buf);
+unsigned if_nametoindex(const char* __name);
 struct if_nameindex* if_nameindex(void) __INTRODUCED_IN(24);
-void if_freenameindex(struct if_nameindex*) __INTRODUCED_IN(24);
+void if_freenameindex(struct if_nameindex* __ptr) __INTRODUCED_IN(24);
 
 __END_DECLS
 
diff --git a/libc/include/netdb.h b/libc/include/netdb.h
index 816acc5..66ec8e3 100644
--- a/libc/include/netdb.h
+++ b/libc/include/netdb.h
@@ -196,37 +196,33 @@
 
 __BEGIN_DECLS
 
-/* BIONIC-BEGIN */
-#define  h_errno   (*__get_h_errno())
-int*  __get_h_errno(void);
-/* BIONIC-END */
+#define h_errno (*__get_h_errno())
+int* __get_h_errno(void);
 void endservent(void);
-struct hostent* gethostbyaddr(const void*, socklen_t, int);
-int gethostbyaddr_r(const void*, socklen_t, int, struct hostent*, char*, size_t, struct hostent**,
-                    int*) __INTRODUCED_IN(23);
-struct hostent* gethostbyname(const char*);
-int gethostbyname_r(const char*, struct hostent*, char*, size_t, struct hostent**, int*);
-struct hostent* gethostbyname2(const char*, int);
-int gethostbyname2_r(const char*, int, struct hostent*, char*, size_t, struct hostent**, int*)
-  __INTRODUCED_IN(23);
+struct hostent* gethostbyaddr(const void* __addr, socklen_t __length, int __type);
+int gethostbyaddr_r(const void* __addr, socklen_t __length, int __type, struct hostent* __ret, char* __buf, size_t __buf_size, struct hostent** __result, int* __h_errno_ptr) __INTRODUCED_IN(23);
+struct hostent* gethostbyname(const char* __name);
+int gethostbyname_r(const char* __name, struct hostent* __ret, char* __buf, size_t __buf_size, struct hostent** __result, int* __h_errno_ptr);
+struct hostent* gethostbyname2(const char* __name, int __af);
+int gethostbyname2_r(const char* __name, int __af, struct hostent* __ret, char* __buf, size_t __buf_size, struct hostent** __result, int* __h_errno_ptr) __INTRODUCED_IN(23);
 struct hostent* gethostent(void);
-struct netent* getnetbyaddr(uint32_t, int);
-struct netent* getnetbyname(const char*);
-struct protoent* getprotobyname(const char*);
-struct protoent* getprotobynumber(int);
-struct servent* getservbyname(const char*, const char*);
-struct servent* getservbyport(int, const char*);
+struct netent* getnetbyaddr(uint32_t __net, int __type);
+struct netent* getnetbyname(const char* __name);
+struct protoent* getprotobyname(const char* __name);
+struct protoent* getprotobynumber(int __proto);
+struct servent* getservbyname(const char* __name, const char* __proto);
+struct servent* getservbyport(int __port, const char* __proto);
 struct servent* getservent(void);
-void herror(const char*);
-const char* hstrerror(int);
+void herror(const char* __s);
+const char* hstrerror(int __error);
 
-int getaddrinfo(const char*, const char*, const struct addrinfo*, struct addrinfo**);
+int getaddrinfo(const char* __node, const char* __service, const struct addrinfo* __hints, struct addrinfo** __result);
 /* POSIX getnameinfo uses socklen_t, not size_t, but LP64 sizeof(socklen_t) != sizeof(size_t). */
-int getnameinfo(const struct sockaddr*, socklen_t, char*, size_t, char*, size_t, int);
-void freeaddrinfo(struct addrinfo*);
-const char* gai_strerror(int);
-void setservent(int);
+int getnameinfo(const struct sockaddr* __sa, socklen_t __sa_length, char* __host, size_t __host_length, char* __service, size_t __service_length, int __flags);
+void freeaddrinfo(struct addrinfo* __ptr);
+const char* gai_strerror(int __error);
+void setservent(int __stay_open);
 
 __END_DECLS
 
-#endif /* !_NETDB_H_ */
+#endif
diff --git a/libc/include/netinet/ether.h b/libc/include/netinet/ether.h
index e69cdaf..3e6a4e3 100644
--- a/libc/include/netinet/ether.h
+++ b/libc/include/netinet/ether.h
@@ -34,10 +34,10 @@
 
 __BEGIN_DECLS
 
-char* ether_ntoa(const struct ether_addr*) __INTRODUCED_IN(11);
-char* ether_ntoa_r(const struct ether_addr*, char*) __INTRODUCED_IN(11);
-struct ether_addr* ether_aton(const char*) __INTRODUCED_IN(11);
-struct ether_addr* ether_aton_r(const char*, struct ether_addr*) __INTRODUCED_IN(11);
+char* ether_ntoa(const struct ether_addr* __addr) __INTRODUCED_IN(11);
+char* ether_ntoa_r(const struct ether_addr* __addr, char* __buf) __INTRODUCED_IN(11);
+struct ether_addr* ether_aton(const char* __ascii) __INTRODUCED_IN(11);
+struct ether_addr* ether_aton_r(const char* __ascii, struct ether_addr* __addr) __INTRODUCED_IN(11);
 
 __END_DECLS
 
diff --git a/libc/include/netinet/in.h b/libc/include/netinet/in.h
index 10fbafa..0ca8c82 100644
--- a/libc/include/netinet/in.h
+++ b/libc/include/netinet/in.h
@@ -45,7 +45,7 @@
 typedef uint16_t in_port_t;
 typedef uint32_t in_addr_t;
 
-int bindresvport(int, struct sockaddr_in*);
+int bindresvport(int __fd, struct sockaddr_in* __sin);
 
 #if __ANDROID_API__ >= __ANDROID_API_N__
 extern const struct in6_addr in6addr_any __INTRODUCED_IN(24);
diff --git a/libc/include/nl_types.h b/libc/include/nl_types.h
index d478353..b25b7a3 100644
--- a/libc/include/nl_types.h
+++ b/libc/include/nl_types.h
@@ -39,9 +39,9 @@
 typedef void* nl_catd;
 typedef int nl_item;
 
-nl_catd catopen(const char*, int) __INTRODUCED_IN(26);
-char* catgets(nl_catd, int, int, const char*) __INTRODUCED_IN(26);
-int catclose(nl_catd) __INTRODUCED_IN(26);
+nl_catd catopen(const char* __name, int __flag) __INTRODUCED_IN(26);
+char* catgets(nl_catd __catalog, int __set_number, int __msg_number, const char* __msg) __INTRODUCED_IN(26);
+int catclose(nl_catd __catalog) __INTRODUCED_IN(26);
 
 __END_DECLS
 
diff --git a/libc/include/poll.h b/libc/include/poll.h
index 0f5758d..8517dc6 100644
--- a/libc/include/poll.h
+++ b/libc/include/poll.h
@@ -38,9 +38,8 @@
 
 typedef unsigned int nfds_t;
 
-int poll(struct pollfd*, nfds_t, int) __overloadable __RENAME_CLANG(poll);
-int ppoll(struct pollfd*, nfds_t, const struct timespec*, const sigset_t*)
-        __overloadable __RENAME_CLANG(ppoll) __INTRODUCED_IN(21);
+int poll(struct pollfd* __fds, nfds_t __count, int __timeout_ms) __overloadable __RENAME_CLANG(poll);
+int ppoll(struct pollfd* __fds, nfds_t __count, const struct timespec* __timeout, const sigset_t* __mask) __overloadable __RENAME_CLANG(ppoll) __INTRODUCED_IN(21);
 
 #if defined(__BIONIC_INCLUDE_FORTIFY_HEADERS)
 #include <bits/fortify/poll.h>
@@ -48,4 +47,4 @@
 
 __END_DECLS
 
-#endif /* _POLL_H_ */
+#endif
diff --git a/libc/include/pthread.h b/libc/include/pthread.h
index ccafd78..32315fe 100644
--- a/libc/include/pthread.h
+++ b/libc/include/pthread.h
@@ -39,14 +39,14 @@
 __BEGIN_DECLS
 
 enum {
-    PTHREAD_MUTEX_NORMAL = 0,
-    PTHREAD_MUTEX_RECURSIVE = 1,
-    PTHREAD_MUTEX_ERRORCHECK = 2,
+  PTHREAD_MUTEX_NORMAL = 0,
+  PTHREAD_MUTEX_RECURSIVE = 1,
+  PTHREAD_MUTEX_ERRORCHECK = 2,
 
-    PTHREAD_MUTEX_ERRORCHECK_NP = PTHREAD_MUTEX_ERRORCHECK,
-    PTHREAD_MUTEX_RECURSIVE_NP  = PTHREAD_MUTEX_RECURSIVE,
+  PTHREAD_MUTEX_ERRORCHECK_NP = PTHREAD_MUTEX_ERRORCHECK,
+  PTHREAD_MUTEX_RECURSIVE_NP  = PTHREAD_MUTEX_RECURSIVE,
 
-    PTHREAD_MUTEX_DEFAULT = PTHREAD_MUTEX_NORMAL
+  PTHREAD_MUTEX_DEFAULT = PTHREAD_MUTEX_NORMAL
 };
 
 #define PTHREAD_MUTEX_INITIALIZER { { ((PTHREAD_MUTEX_NORMAL & 3) << 14) } }
@@ -83,74 +83,74 @@
 #define PTHREAD_SCOPE_SYSTEM     0
 #define PTHREAD_SCOPE_PROCESS    1
 
-int pthread_atfork(void (*)(void), void (*)(void), void (*)(void)) __INTRODUCED_IN(12);
+int pthread_atfork(void (*__prepare)(void), void (*__parent)(void), void (*__child)(void)) __INTRODUCED_IN(12);
 
-int pthread_attr_destroy(pthread_attr_t*);
-int pthread_attr_getdetachstate(const pthread_attr_t*, int*);
-int pthread_attr_getguardsize(const pthread_attr_t*, size_t*);
-int pthread_attr_getschedparam(const pthread_attr_t*, struct sched_param*);
-int pthread_attr_getschedpolicy(const pthread_attr_t*, int*);
-int pthread_attr_getscope(const pthread_attr_t*, int*);
-int pthread_attr_getstack(const pthread_attr_t*, void**, size_t*);
-int pthread_attr_getstacksize(const pthread_attr_t*, size_t*);
-int pthread_attr_init(pthread_attr_t*);
-int pthread_attr_setdetachstate(pthread_attr_t*, int);
-int pthread_attr_setguardsize(pthread_attr_t*, size_t);
-int pthread_attr_setschedparam(pthread_attr_t*, const struct sched_param*);
-int pthread_attr_setschedpolicy(pthread_attr_t*, int);
-int pthread_attr_setscope(pthread_attr_t*, int);
-int pthread_attr_setstack(pthread_attr_t*, void*, size_t);
-int pthread_attr_setstacksize(pthread_attr_t*, size_t);
+int pthread_attr_destroy(pthread_attr_t* __attr);
+int pthread_attr_getdetachstate(const pthread_attr_t* __attr, int* __state);
+int pthread_attr_getguardsize(const pthread_attr_t* __attr, size_t* __size);
+int pthread_attr_getschedparam(const pthread_attr_t* __attr, struct sched_param* __param);
+int pthread_attr_getschedpolicy(const pthread_attr_t* __attr, int* __policy);
+int pthread_attr_getscope(const pthread_attr_t* __attr, int* __scope);
+int pthread_attr_getstack(const pthread_attr_t* __attr, void** __addr, size_t* __size);
+int pthread_attr_getstacksize(const pthread_attr_t* __attr, size_t* __size);
+int pthread_attr_init(pthread_attr_t* __attr);
+int pthread_attr_setdetachstate(pthread_attr_t* __attr, int __state);
+int pthread_attr_setguardsize(pthread_attr_t* __attr, size_t __size);
+int pthread_attr_setschedparam(pthread_attr_t* __attr, const struct sched_param* __param);
+int pthread_attr_setschedpolicy(pthread_attr_t* __attr, int __policy);
+int pthread_attr_setscope(pthread_attr_t* __attr, int __scope);
+int pthread_attr_setstack(pthread_attr_t* __attr, void* __addr, size_t __size);
+int pthread_attr_setstacksize(pthread_attr_t* __addr, size_t __size);
 
-int pthread_condattr_destroy(pthread_condattr_t*);
-int pthread_condattr_getclock(const pthread_condattr_t*, clockid_t*) __INTRODUCED_IN(21);
-int pthread_condattr_getpshared(const pthread_condattr_t*, int*);
-int pthread_condattr_init(pthread_condattr_t*);
-int pthread_condattr_setclock(pthread_condattr_t*, clockid_t) __INTRODUCED_IN(21);
-int pthread_condattr_setpshared(pthread_condattr_t*, int);
+int pthread_condattr_destroy(pthread_condattr_t* __attr);
+int pthread_condattr_getclock(const pthread_condattr_t* __attr, clockid_t* __clock) __INTRODUCED_IN(21);
+int pthread_condattr_getpshared(const pthread_condattr_t* __attr, int* __shared);
+int pthread_condattr_init(pthread_condattr_t* __attr);
+int pthread_condattr_setclock(pthread_condattr_t* __attr, clockid_t __clock) __INTRODUCED_IN(21);
+int pthread_condattr_setpshared(pthread_condattr_t* __attr, int __shared);
 
-int pthread_cond_broadcast(pthread_cond_t*);
-int pthread_cond_destroy(pthread_cond_t*);
-int pthread_cond_init(pthread_cond_t*, const pthread_condattr_t*);
-int pthread_cond_signal(pthread_cond_t*);
-int pthread_cond_timedwait(pthread_cond_t*, pthread_mutex_t*, const struct timespec*);
-int pthread_cond_wait(pthread_cond_t*, pthread_mutex_t*);
+int pthread_cond_broadcast(pthread_cond_t* __cond);
+int pthread_cond_destroy(pthread_cond_t* __cond);
+int pthread_cond_init(pthread_cond_t* __cond, const pthread_condattr_t* __attr);
+int pthread_cond_signal(pthread_cond_t* __cond);
+int pthread_cond_timedwait(pthread_cond_t* __cond, pthread_mutex_t* __mutex, const struct timespec* __timeout);
+int pthread_cond_wait(pthread_cond_t* __cond, pthread_mutex_t* __mutex);
 
-int pthread_create(pthread_t*, pthread_attr_t const*, void* (*start_routine)(void*), void*);
-int pthread_detach(pthread_t);
-void pthread_exit(void*) __noreturn;
+int pthread_create(pthread_t* __pthread_ptr, pthread_attr_t const* __attr, void* (*__start_routine)(void*), void*);
+int pthread_detach(pthread_t __pthread);
+void pthread_exit(void* __return_value) __noreturn;
 
-int pthread_equal(pthread_t, pthread_t);
+int pthread_equal(pthread_t __lhs, pthread_t __rhs);
 
-int pthread_getattr_np(pthread_t, pthread_attr_t*);
+int pthread_getattr_np(pthread_t __pthread, pthread_attr_t* __attr);
 
-int pthread_getcpuclockid(pthread_t, clockid_t*);
+int pthread_getcpuclockid(pthread_t __pthread, clockid_t* __clock);
 
-int pthread_getschedparam(pthread_t, int*, struct sched_param*);
+int pthread_getschedparam(pthread_t __pthread, int* __policy, struct sched_param* __param);
 
-void* pthread_getspecific(pthread_key_t);
+void* pthread_getspecific(pthread_key_t __key);
 
-pid_t pthread_gettid_np(pthread_t) __INTRODUCED_IN(21);
+pid_t pthread_gettid_np(pthread_t __pthread) __INTRODUCED_IN(21);
 
-int pthread_join(pthread_t, void**);
+int pthread_join(pthread_t __pthread, void** __return_value_ptr);
 
-int pthread_key_create(pthread_key_t*, void (*)(void*));
-int pthread_key_delete(pthread_key_t);
+int pthread_key_create(pthread_key_t* __key_ptr, void (*__key_destructor)(void*));
+int pthread_key_delete(pthread_key_t __key);
 
-int pthread_mutexattr_destroy(pthread_mutexattr_t*);
-int pthread_mutexattr_getpshared(const pthread_mutexattr_t*, int*);
-int pthread_mutexattr_gettype(const pthread_mutexattr_t*, int*);
-int pthread_mutexattr_init(pthread_mutexattr_t*);
-int pthread_mutexattr_setpshared(pthread_mutexattr_t*, int);
-int pthread_mutexattr_settype(pthread_mutexattr_t*, int);
+int pthread_mutexattr_destroy(pthread_mutexattr_t* __attr);
+int pthread_mutexattr_getpshared(const pthread_mutexattr_t* __attr, int* __shared);
+int pthread_mutexattr_gettype(const pthread_mutexattr_t* __attr, int* __type);
+int pthread_mutexattr_init(pthread_mutexattr_t* __attr);
+int pthread_mutexattr_setpshared(pthread_mutexattr_t* __attr, int __shared);
+int pthread_mutexattr_settype(pthread_mutexattr_t* __attr, int __type);
 
-int pthread_mutex_destroy(pthread_mutex_t*);
-int pthread_mutex_init(pthread_mutex_t*, const pthread_mutexattr_t*);
-int pthread_mutex_lock(pthread_mutex_t*);
-int pthread_mutex_timedlock(pthread_mutex_t*, const struct timespec* )
+int pthread_mutex_destroy(pthread_mutex_t* __mutex);
+int pthread_mutex_init(pthread_mutex_t* __mutex, const pthread_mutexattr_t* __attr);
+int pthread_mutex_lock(pthread_mutex_t* __mutex);
+int pthread_mutex_timedlock(pthread_mutex_t* __mutex, const struct timespec* __timeout)
   __INTRODUCED_IN(21);
-int pthread_mutex_trylock(pthread_mutex_t*);
-int pthread_mutex_unlock(pthread_mutex_t*);
+int pthread_mutex_trylock(pthread_mutex_t* __mutex);
+int pthread_mutex_unlock(pthread_mutex_t* __mutex);
 
 #if __ANDROID_API__ < 21
 /*
@@ -164,68 +164,64 @@
  *  * https://github.com/android-ndk/ndk/issues/423
  *  * https://stackoverflow.com/q/44580542/632035
  */
-int pthread_mutex_lock_timeout_np(pthread_mutex_t* mutex, unsigned msecs);
-int pthread_cond_timeout_np(pthread_cond_t* cond, pthread_mutex_t* mutex, unsigned msecs);
-int pthread_cond_timedwait_monotonic_np(pthread_cond_t*, pthread_mutex_t*, const struct timespec*);
-int pthread_cond_timedwait_relative_np(pthread_cond_t* cond, pthread_mutex_t* mutex,
-                                       const struct timespec* reltime);
+int pthread_mutex_lock_timeout_np(pthread_mutex_t* __mutex, unsigned __timeout_ms);
+int pthread_cond_timeout_np(pthread_cond_t* __cond, pthread_mutex_t* __mutex, unsigned __timeout_ms);
+int pthread_cond_timedwait_monotonic_np(pthread_cond_t* __cond, pthread_mutex_t* __mutex, const struct timespec* __timeout);
+int pthread_cond_timedwait_relative_np(pthread_cond_t* __cond, pthread_mutex_t* __mutex, const struct timespec* __relative_timeout);
 #endif
 
-int pthread_once(pthread_once_t*, void (*init_routine)(void));
+int pthread_once(pthread_once_t* __once, void (*__init_routine)(void));
 
-int pthread_rwlockattr_init(pthread_rwlockattr_t*);
-int pthread_rwlockattr_destroy(pthread_rwlockattr_t*);
-int pthread_rwlockattr_getpshared(const pthread_rwlockattr_t*, int*);
-int pthread_rwlockattr_setpshared(pthread_rwlockattr_t*, int);
-int pthread_rwlockattr_getkind_np(const pthread_rwlockattr_t*, int*)
+int pthread_rwlockattr_init(pthread_rwlockattr_t* __attr);
+int pthread_rwlockattr_destroy(pthread_rwlockattr_t* __attr);
+int pthread_rwlockattr_getpshared(const pthread_rwlockattr_t* __attr, int* __shared);
+int pthread_rwlockattr_setpshared(pthread_rwlockattr_t* __attr, int __shared);
+int pthread_rwlockattr_getkind_np(const pthread_rwlockattr_t* __attr, int* __kind)
   __INTRODUCED_IN(23);
-int pthread_rwlockattr_setkind_np(pthread_rwlockattr_t*, int) __INTRODUCED_IN(23);
+int pthread_rwlockattr_setkind_np(pthread_rwlockattr_t* __attr, int __kind) __INTRODUCED_IN(23);
 
-int pthread_rwlock_destroy(pthread_rwlock_t*);
-int pthread_rwlock_init(pthread_rwlock_t*, const pthread_rwlockattr_t*);
-int pthread_rwlock_rdlock(pthread_rwlock_t*);
-int pthread_rwlock_timedrdlock(pthread_rwlock_t*, const struct timespec*);
-int pthread_rwlock_timedwrlock(pthread_rwlock_t*, const struct timespec*);
-int pthread_rwlock_tryrdlock(pthread_rwlock_t*);
-int pthread_rwlock_trywrlock(pthread_rwlock_t*);
-int pthread_rwlock_unlock(pthread_rwlock_t*);
-int pthread_rwlock_wrlock(pthread_rwlock_t*);
+int pthread_rwlock_destroy(pthread_rwlock_t* __rwlock);
+int pthread_rwlock_init(pthread_rwlock_t* __rwlock, const pthread_rwlockattr_t* __attr);
+int pthread_rwlock_rdlock(pthread_rwlock_t* __rwlock);
+int pthread_rwlock_timedrdlock(pthread_rwlock_t* __rwlock, const struct timespec* __timeout);
+int pthread_rwlock_timedwrlock(pthread_rwlock_t* __rwlock, const struct timespec* __timeout);
+int pthread_rwlock_tryrdlock(pthread_rwlock_t* __rwlock);
+int pthread_rwlock_trywrlock(pthread_rwlock_t* __rwlock);
+int pthread_rwlock_unlock(pthread_rwlock_t* __rwlock);
+int pthread_rwlock_wrlock(pthread_rwlock_t* __rwlock);
 
 #if __ANDROID_API__ >= __ANDROID_API_N__
-int pthread_barrierattr_init(pthread_barrierattr_t* attr) __INTRODUCED_IN(24);
-int pthread_barrierattr_destroy(pthread_barrierattr_t* attr) __INTRODUCED_IN(24);
-int pthread_barrierattr_getpshared(const pthread_barrierattr_t* attr,
-                                   int* pshared) __INTRODUCED_IN(24);
-int pthread_barrierattr_setpshared(pthread_barrierattr_t* attr, int pshared)
-  __INTRODUCED_IN(24);
+int pthread_barrierattr_init(pthread_barrierattr_t* __attr) __INTRODUCED_IN(24);
+int pthread_barrierattr_destroy(pthread_barrierattr_t* __attr) __INTRODUCED_IN(24);
+int pthread_barrierattr_getpshared(const pthread_barrierattr_t* __attr, int* __shared) __INTRODUCED_IN(24);
+int pthread_barrierattr_setpshared(pthread_barrierattr_t* __attr, int __shared) __INTRODUCED_IN(24);
 #endif
 
 #if __ANDROID_API__ >= __ANDROID_API_N__
-int pthread_barrier_init(pthread_barrier_t*, const pthread_barrierattr_t*, unsigned)
-  __INTRODUCED_IN(24);
-int pthread_barrier_destroy(pthread_barrier_t*) __INTRODUCED_IN(24);
-int pthread_barrier_wait(pthread_barrier_t*) __INTRODUCED_IN(24);
+int pthread_barrier_init(pthread_barrier_t* __barrier, const pthread_barrierattr_t* __attr, unsigned __count) __INTRODUCED_IN(24);
+int pthread_barrier_destroy(pthread_barrier_t* __barrier) __INTRODUCED_IN(24);
+int pthread_barrier_wait(pthread_barrier_t* __barrier) __INTRODUCED_IN(24);
 #endif
 
 #if __ANDROID_API__ >= __ANDROID_API_N__
-int pthread_spin_destroy(pthread_spinlock_t*) __INTRODUCED_IN(24);
-int pthread_spin_init(pthread_spinlock_t*, int) __INTRODUCED_IN(24);
-int pthread_spin_lock(pthread_spinlock_t*) __INTRODUCED_IN(24);
-int pthread_spin_trylock(pthread_spinlock_t*) __INTRODUCED_IN(24);
-int pthread_spin_unlock(pthread_spinlock_t*) __INTRODUCED_IN(24);
+int pthread_spin_destroy(pthread_spinlock_t* __spinlock) __INTRODUCED_IN(24);
+int pthread_spin_init(pthread_spinlock_t* __spinlock, int __shared) __INTRODUCED_IN(24);
+int pthread_spin_lock(pthread_spinlock_t* __spinlock) __INTRODUCED_IN(24);
+int pthread_spin_trylock(pthread_spinlock_t* __spinlock) __INTRODUCED_IN(24);
+int pthread_spin_unlock(pthread_spinlock_t* __spinlock) __INTRODUCED_IN(24);
 #endif
 
 pthread_t pthread_self(void) __attribute_const__;
 
 #if defined(__USE_GNU)
-int pthread_getname_np(pthread_t, char*, size_t) __INTRODUCED_IN(26);
+int pthread_getname_np(pthread_t __pthread, char* __buf, size_t __n) __INTRODUCED_IN(26);
 #endif
 /* TODO: this should be __USE_GNU too. */
-int pthread_setname_np(pthread_t, const char*);
+int pthread_setname_np(pthread_t __pthread, const char* __name);
 
-int pthread_setschedparam(pthread_t, int, const struct sched_param*);
+int pthread_setschedparam(pthread_t __pthread, int __policy, const struct sched_param* __param);
 
-int pthread_setspecific(pthread_key_t, const void*);
+int pthread_setspecific(pthread_key_t __key, const void* __value);
 
 typedef void (*__pthread_cleanup_func_t)(void*);
 
@@ -255,4 +251,4 @@
 
 __END_DECLS
 
-#endif /* _PTHREAD_H_ */
+#endif
diff --git a/libc/include/pty.h b/libc/include/pty.h
index ec257a5..cf9ccb9 100644
--- a/libc/include/pty.h
+++ b/libc/include/pty.h
@@ -36,9 +36,9 @@
 
 __BEGIN_DECLS
 
-int openpty(int*, int*, char*, const struct termios*, const struct winsize*) __INTRODUCED_IN(23);
-int forkpty(int*, char*, const struct termios*, const struct winsize*) __INTRODUCED_IN(23);
+int openpty(int* __master_fd, int* __slave_fd, char* __slave_name, const struct termios* __termios_ptr, const struct winsize* __winsize_ptr) __INTRODUCED_IN(23);
+int forkpty(int* __master_fd, char* __slave_name, const struct termios* __termios_ptr, const struct winsize* __winsize_ptr) __INTRODUCED_IN(23);
 
 __END_DECLS
 
-#endif /* _PTY_H */
+#endif
diff --git a/libc/include/pwd.h b/libc/include/pwd.h
index e37c637..5c516d7 100644
--- a/libc/include/pwd.h
+++ b/libc/include/pwd.h
@@ -80,8 +80,8 @@
   char* pw_shell;
 };
 
-struct passwd* getpwnam(const char*);
-struct passwd* getpwuid(uid_t);
+struct passwd* getpwnam(const char* __name);
+struct passwd* getpwuid(uid_t __uid);
 
 /* Note: Android has thousands and thousands of ids to iterate through */
 struct passwd* getpwent(void) __INTRODUCED_IN(26);
@@ -89,8 +89,8 @@
 void setpwent(void) __INTRODUCED_IN(26);
 void endpwent(void) __INTRODUCED_IN(26);
 
-int getpwnam_r(const char*, struct passwd*, char*, size_t, struct passwd**) __INTRODUCED_IN(12);
-int getpwuid_r(uid_t, struct passwd*, char*, size_t, struct passwd**) __INTRODUCED_IN(12);
+int getpwnam_r(const char* __name, struct passwd* __pwd, char* __buf, size_t __n, struct passwd** __result) __INTRODUCED_IN(12);
+int getpwuid_r(uid_t __uid, struct passwd* __pwd, char* __buf, size_t __n, struct passwd** __result) __INTRODUCED_IN(12);
 
 __END_DECLS
 
diff --git a/libc/include/regex.h b/libc/include/regex.h
index b06a515..c4cc39c 100644
--- a/libc/include/regex.h
+++ b/libc/include/regex.h
@@ -97,10 +97,10 @@
 #define	REG_BACKR	02000	/* force use of backref code */
 
 __BEGIN_DECLS
-int	regcomp(regex_t *, const char *, int);
-size_t	regerror(int, const regex_t *, char *, size_t);
-int	regexec(const regex_t *, const char *, size_t, regmatch_t [], int);
-void	regfree(regex_t *);
+int regcomp(regex_t* __re, const char* __regex, int __flags);
+size_t regerror(int __error_code, const regex_t* __re, char* __buf, size_t __n);
+int regexec(const regex_t* __re, const char* __s, size_t __match_count, regmatch_t __matches[], int __flags);
+void regfree(regex_t* __re);
 __END_DECLS
 
-#endif /* !_REGEX_H_ */
+#endif
diff --git a/libc/include/sched.h b/libc/include/sched.h
index b8ef44b..de6969f8 100644
--- a/libc/include/sched.h
+++ b/libc/include/sched.h
@@ -42,22 +42,22 @@
   int sched_priority;
 };
 
-int sched_setscheduler(pid_t pid, int policy, const struct sched_param* param);
-int sched_getscheduler(pid_t pid);
+int sched_setscheduler(pid_t __pid, int __policy, const struct sched_param* __param);
+int sched_getscheduler(pid_t __pid);
 int sched_yield(void);
-int sched_get_priority_max(int policy);
-int sched_get_priority_min(int policy);
-int sched_setparam(pid_t pid, const struct sched_param* param);
-int sched_getparam(pid_t pid, struct sched_param* param);
-int sched_rr_get_interval(pid_t pid, struct timespec* quantum);
+int sched_get_priority_max(int __policy);
+int sched_get_priority_min(int __policy);
+int sched_setparam(pid_t __pid, const struct sched_param* __param);
+int sched_getparam(pid_t __pid, struct sched_param* __param);
+int sched_rr_get_interval(pid_t __pid, struct timespec* __quantum);
 
 #if defined(__USE_GNU)
 
-int clone(int (*fn)(void*), void* child_stack, int flags, void* arg, ...)
+int clone(int (*__fn)(void*), void* __child_stack, int __flags, void* __arg, ...)
     __INTRODUCED_IN_ARM(9) __INTRODUCED_IN_MIPS(12) __INTRODUCED_IN_X86(17);
-int unshare(int flags) __INTRODUCED_IN(17);
+int unshare(int __flags) __INTRODUCED_IN(17);
 int sched_getcpu(void) __INTRODUCED_IN(12);
-int setns(int fd, int ns_type) __INTRODUCED_IN(21);
+int setns(int __fd, int __ns_type) __INTRODUCED_IN(21);
 
 #ifdef __LP64__
 #define CPU_SETSIZE 1024
@@ -74,8 +74,8 @@
   __CPU_BITTYPE  __bits[ CPU_SETSIZE / __CPU_BITS ];
 } cpu_set_t;
 
-int sched_setaffinity(pid_t pid, size_t setsize, const cpu_set_t* set) __INTRODUCED_IN(12);
-int sched_getaffinity(pid_t pid, size_t setsize, cpu_set_t* set) __INTRODUCED_IN(12);
+int sched_setaffinity(pid_t __pid, size_t __set_size, const cpu_set_t* __set) __INTRODUCED_IN(12);
+int sched_getaffinity(pid_t __pid, size_t __set_size, cpu_set_t* __set) __INTRODUCED_IN(12);
 
 #define CPU_ZERO(set)          CPU_ZERO_S(sizeof(cpu_set_t), set)
 #define CPU_SET(cpu, set)      CPU_SET_S(cpu, sizeof(cpu_set_t), set)
@@ -98,8 +98,8 @@
 #define CPU_ALLOC(count)  __sched_cpualloc((count))
 #define CPU_FREE(set)     __sched_cpufree((set))
 
-cpu_set_t* __sched_cpualloc(size_t count) __INTRODUCED_IN(12);
-void __sched_cpufree(cpu_set_t* set) __INTRODUCED_IN(12);
+cpu_set_t* __sched_cpualloc(size_t __count) __INTRODUCED_IN(12);
+void __sched_cpufree(cpu_set_t* __set) __INTRODUCED_IN(12);
 
 #define CPU_ZERO_S(setsize, set)  __builtin_memset(set, 0, setsize)
 
@@ -143,7 +143,7 @@
 
 #define CPU_COUNT_S(setsize, set)  __sched_cpucount((setsize), (set))
 
-int __sched_cpucount(size_t setsize, cpu_set_t* set) __INTRODUCED_IN(12);
+int __sched_cpucount(size_t __set_size, cpu_set_t* __set) __INTRODUCED_IN(12);
 
 #endif /* __USE_GNU */
 
diff --git a/libc/include/search.h b/libc/include/search.h
index 46998d9..0015699 100644
--- a/libc/include/search.h
+++ b/libc/include/search.h
@@ -29,21 +29,20 @@
 
 __BEGIN_DECLS
 
-void insque(void*, void*) __INTRODUCED_IN(21);
-void remque(void*) __INTRODUCED_IN(21);
+void insque(void* __element, void* __previous) __INTRODUCED_IN(21);
+void remque(void* __element) __INTRODUCED_IN(21);
 
-void* lfind(const void*, const void*, size_t*, size_t, int (*)(const void*, const void*))
+void* lfind(const void* __key, const void* __base, size_t* __count, size_t __size, int (*__comparator)(const void*, const void*))
   __INTRODUCED_IN(21);
-void* lsearch(const void*, void*, size_t*, size_t, int (*)(const void*, const void*))
+void* lsearch(const void* __key, void* __base, size_t* __count, size_t __size, int (*__comparator)(const void*, const void*))
   __INTRODUCED_IN(21);
 
-void* tdelete(const void*, void**, int (*)(const void*, const void*))
-  __INTRODUCED_IN(16);
-void tdestroy(void*, void (*)(void*)) __INTRODUCED_IN(16);
-void* tfind(const void*, void* const*, int (*)(const void*, const void*)) __INTRODUCED_IN(16);
-void* tsearch(const void*, void**, int (*)(const void*, const void*)) __INTRODUCED_IN(16);
-void twalk(const void*, void (*)(const void*, VISIT, int)) __INTRODUCED_IN(21);
+void* tdelete(const void* __key, void** __root_ptr, int (*__comparator)(const void*, const void*)) __INTRODUCED_IN(16);
+void tdestroy(void* __root, void (*__free_fn)(void*)) __INTRODUCED_IN(16);
+void* tfind(const void* __key, void* const* __root_ptr, int (*__comparator)(const void*, const void*)) __INTRODUCED_IN(16);
+void* tsearch(const void* __key, void** __root_ptr, int (*__comparator)(const void*, const void*)) __INTRODUCED_IN(16);
+void twalk(const void* __root, void (*__visitor)(const void*, VISIT, int)) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif /* !_SEARCH_H_ */
+#endif
diff --git a/libc/include/semaphore.h b/libc/include/semaphore.h
index 218f22a..7e3dc1c 100644
--- a/libc/include/semaphore.h
+++ b/libc/include/semaphore.h
@@ -44,19 +44,19 @@
 
 #define SEM_FAILED __BIONIC_CAST(reinterpret_cast, sem_t*, 0)
 
-int sem_destroy(sem_t*);
-int sem_getvalue(sem_t*, int*);
-int sem_init(sem_t*, int, unsigned int);
-int sem_post(sem_t*);
-int sem_timedwait(sem_t*, const struct timespec*);
-int sem_trywait(sem_t*);
-int sem_wait(sem_t*);
+int sem_destroy(sem_t* __sem);
+int sem_getvalue(sem_t* __sem, int* __value);
+int sem_init(sem_t* __sem, int __shared, unsigned int __value);
+int sem_post(sem_t* __sem);
+int sem_timedwait(sem_t* __sem, const struct timespec* __ts);
+int sem_trywait(sem_t* __sem);
+int sem_wait(sem_t* __sem);
 
 /* These aren't actually implemented. */
-sem_t* sem_open(const char*, int, ...);
-int sem_close(sem_t*);
-int sem_unlink(const char*);
+sem_t* sem_open(const char* __name, int _flags, ...);
+int sem_close(sem_t* __sem);
+int sem_unlink(const char* __name);
 
 __END_DECLS
 
-#endif /* _SEMAPHORE_H */
+#endif
diff --git a/libc/include/setjmp.h b/libc/include/setjmp.h
index 7adeb35..12a3083 100644
--- a/libc/include/setjmp.h
+++ b/libc/include/setjmp.h
@@ -48,17 +48,17 @@
 
 __BEGIN_DECLS
 
-int     _setjmp(jmp_buf);
-void    _longjmp(jmp_buf, int);
+int _setjmp(jmp_buf __env);
+void _longjmp(jmp_buf __env, int __value);
 
-int     setjmp(jmp_buf);
-void    longjmp(jmp_buf, int);
+int setjmp(jmp_buf __env);
+void longjmp(jmp_buf __env, int __value);
 
-int sigsetjmp(sigjmp_buf, int) __INTRODUCED_IN_ARM(9) __INTRODUCED_IN_MIPS(12)
-    __INTRODUCED_IN_X86(12);
-void siglongjmp(sigjmp_buf, int) __INTRODUCED_IN_ARM(9) __INTRODUCED_IN_MIPS(12)
-    __INTRODUCED_IN_X86(12);
+int sigsetjmp(sigjmp_buf __env, int __save_signal_mask)
+    __INTRODUCED_IN_ARM(9) __INTRODUCED_IN_MIPS(12) __INTRODUCED_IN_X86(12);
+void siglongjmp(sigjmp_buf __env, int __value)
+    __INTRODUCED_IN_ARM(9) __INTRODUCED_IN_MIPS(12) __INTRODUCED_IN_X86(12);
 
 __END_DECLS
 
-#endif /* !_SETJMP_H_ */
+#endif
diff --git a/libc/include/signal.h b/libc/include/signal.h
index 89d85fc..ece2916 100644
--- a/libc/include/signal.h
+++ b/libc/include/signal.h
@@ -109,55 +109,55 @@
 
 #endif
 
-int sigaction(int, const struct sigaction*, struct sigaction*);
+int sigaction(int __signal, const struct sigaction* __new_action, struct sigaction* __old_action);
 
-int siginterrupt(int, int);
+int siginterrupt(int __signal, int __flag);
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
-sighandler_t signal(int, sighandler_t) __INTRODUCED_IN(21);
-int sigaddset(sigset_t*, int) __INTRODUCED_IN(21);
-int sigdelset(sigset_t*, int) __INTRODUCED_IN(21);
-int sigemptyset(sigset_t*) __INTRODUCED_IN(21);
-int sigfillset(sigset_t*) __INTRODUCED_IN(21);
-int sigismember(const sigset_t*, int) __INTRODUCED_IN(21);
+sighandler_t signal(int __signal, sighandler_t __handler) __INTRODUCED_IN(21);
+int sigaddset(sigset_t* __set, int __signal) __INTRODUCED_IN(21);
+int sigdelset(sigset_t* __set, int __signal) __INTRODUCED_IN(21);
+int sigemptyset(sigset_t* __set) __INTRODUCED_IN(21);
+int sigfillset(sigset_t* __set) __INTRODUCED_IN(21);
+int sigismember(const sigset_t* __set, int __signal) __INTRODUCED_IN(21);
 #else
 // Implemented as static inlines before 21.
 #endif
 
-int sigpending(sigset_t*);
-int sigprocmask(int, const sigset_t*, sigset_t*);
-int sigsuspend(const sigset_t*);
-int sigwait(const sigset_t*, int*);
+int sigpending(sigset_t* __set);
+int sigprocmask(int __how, const sigset_t* __new_set, sigset_t* __old_set);
+int sigsuspend(const sigset_t* __mask);
+int sigwait(const sigset_t* __set, int* __signal);
 
-int sighold(int)
+int sighold(int __signal)
   __attribute__((deprecated("use sigprocmask() or pthread_sigmask() instead")))
   __INTRODUCED_IN(26);
-int sigignore(int)
+int sigignore(int __signal)
   __attribute__((deprecated("use sigaction() instead"))) __INTRODUCED_IN(26);
-int sigpause(int)
+int sigpause(int __signal)
   __attribute__((deprecated("use sigsuspend() instead"))) __INTRODUCED_IN(26);
-int sigrelse(int)
+int sigrelse(int __signal)
   __attribute__((deprecated("use sigprocmask() or pthread_sigmask() instead")))
   __INTRODUCED_IN(26);
-sighandler_t sigset(int, sighandler_t)
+sighandler_t sigset(int __signal, sighandler_t __handler)
   __attribute__((deprecated("use sigaction() instead"))) __INTRODUCED_IN(26);
 
-int raise(int);
-int kill(pid_t, int);
-int killpg(int, int);
-int tgkill(int tgid, int tid, int sig) __INTRODUCED_IN_32(16);
+int raise(int __signal);
+int kill(pid_t __pid, int __signal);
+int killpg(int __pgrp, int __signal);
+int tgkill(int __tgid, int __tid, int __signal) __INTRODUCED_IN_32(16);
 
-int sigaltstack(const stack_t*, stack_t*);
+int sigaltstack(const stack_t* __new_signal_stack, stack_t* __old_signal_stack);
 
-void psiginfo(const siginfo_t*, const char*) __INTRODUCED_IN(17);
-void psignal(int, const char*) __INTRODUCED_IN(17);
+void psiginfo(const siginfo_t* __info, const char* __msg) __INTRODUCED_IN(17);
+void psignal(int __signal, const char* __msg) __INTRODUCED_IN(17);
 
-int pthread_kill(pthread_t, int);
-int pthread_sigmask(int, const sigset_t*, sigset_t*);
+int pthread_kill(pthread_t __pthread, int __signal);
+int pthread_sigmask(int __how, const sigset_t* __new_set, sigset_t* __old_set);
 
-int sigqueue(pid_t, int, const union sigval) __INTRODUCED_IN(23);
-int sigtimedwait(const sigset_t*, siginfo_t*, const struct timespec*) __INTRODUCED_IN(23);
-int sigwaitinfo(const sigset_t*, siginfo_t*) __INTRODUCED_IN(23);
+int sigqueue(pid_t __pid, int __signal, const union sigval __value) __INTRODUCED_IN(23);
+int sigtimedwait(const sigset_t* __set, siginfo_t* __info, const struct timespec* __timeout) __INTRODUCED_IN(23);
+int sigwaitinfo(const sigset_t* __set, siginfo_t* __info) __INTRODUCED_IN(23);
 
 __END_DECLS
 
diff --git a/libc/include/stdio.h b/libc/include/stdio.h
index 4dff48d..559e52a 100644
--- a/libc/include/stdio.h
+++ b/libc/include/stdio.h
@@ -103,48 +103,42 @@
 #define L_tmpnam 4096
 #define TMP_MAX 308915776
 
-/*
- * Functions defined in ANSI C standard.
- */
-void	 clearerr(FILE *);
-int	 fclose(FILE *);
-int	 feof(FILE *);
-int	 ferror(FILE *);
-int	 fflush(FILE *);
-int	 fgetc(FILE *);
-char	*fgets(char *, int, FILE *) __overloadable
-  __RENAME_CLANG(fgets);
-int	 fprintf(FILE * , const char *, ...) __printflike(2, 3);
-int	 fputc(int, FILE *);
-int	 fputs(const char *, FILE *);
-size_t	 fread(void *, size_t, size_t, FILE *)
-      __overloadable __RENAME_CLANG(fread);
-int	 fscanf(FILE *, const char *, ...) __scanflike(2, 3);
-size_t	 fwrite(const void *, size_t, size_t, FILE *)
-    __overloadable __RENAME_CLANG(fwrite);
-int	 getc(FILE *);
-int	 getchar(void);
-ssize_t getdelim(char**, size_t*, int, FILE*) __INTRODUCED_IN(18);
-ssize_t getline(char**, size_t*, FILE*) __INTRODUCED_IN(18);
+void clearerr(FILE* __fp);
+int fclose(FILE* __fp);
+int feof(FILE* __fp);
+int ferror(FILE* __fp);
+int fflush(FILE* __fp);
+int fgetc(FILE* __fp);
+char* fgets(char* __buf, int __size, FILE* __fp) __overloadable __RENAME_CLANG(fgets);
+int fprintf(FILE* __fp , const char* __fmt, ...) __printflike(2, 3);
+int fputc(int __ch, FILE* __fp);
+int fputs(const char* __s, FILE* __fp);
+size_t fread(void* __buf, size_t __size, size_t __count, FILE* __fp) __overloadable __RENAME_CLANG(fread);
+int fscanf(FILE* __fp, const char* __fmt, ...) __scanflike(2, 3);
+size_t fwrite(const void* __buf, size_t __size, size_t __count, FILE* __fp) __overloadable __RENAME_CLANG(fwrite);
+int getc(FILE* __fp);
+int getchar(void);
+ssize_t getdelim(char** __line_ptr, size_t* __line_length_ptr, int __delimiter, FILE* __fp) __INTRODUCED_IN(18);
+ssize_t getline(char** __line_ptr, size_t* __line_length_ptr, FILE* __fp) __INTRODUCED_IN(18);
 
-void	 perror(const char *);
-int	 printf(const char *, ...) __printflike(1, 2);
-int	 putc(int, FILE *);
-int	 putchar(int);
-int	 puts(const char *);
-int	 remove(const char *);
-void	 rewind(FILE *);
-int	 scanf(const char *, ...) __scanflike(1, 2);
-void	 setbuf(FILE *, char *);
-int	 setvbuf(FILE *, char *, int, size_t);
-int	 sscanf(const char *, const char *, ...) __scanflike(2, 3);
-int	 ungetc(int, FILE *);
-int	 vfprintf(FILE *, const char *, va_list) __printflike(2, 0);
-int	 vprintf(const char *, va_list) __printflike(1, 0);
+void perror(const char* __msg);
+int printf(const char* __fmt, ...) __printflike(1, 2);
+int putc(int __ch, FILE* __fp);
+int putchar(int __ch);
+int puts(const char* __s);
+int remove(const char* __path);
+void rewind(FILE* __fp);
+int scanf(const char* __fmt, ...) __scanflike(1, 2);
+void setbuf(FILE* __fp, char* __buf);
+int setvbuf(FILE* __fp, char* __buf, int __mode, size_t __size);
+int sscanf(const char* __s, const char* __fmt, ...) __scanflike(2, 3);
+int ungetc(int __ch, FILE* __fp);
+int vfprintf(FILE* __fp, const char* __fmt, va_list __args) __printflike(2, 0);
+int vprintf(const char* __fp, va_list __args) __printflike(1, 0);
 
 #if __ANDROID_API__ >= 21
-int dprintf(int, const char*, ...) __printflike(2, 3) __INTRODUCED_IN(21);
-int vdprintf(int, const char*, va_list) __printflike(2, 0) __INTRODUCED_IN(21);
+int dprintf(int __fd, const char* __fmt, ...) __printflike(2, 3) __INTRODUCED_IN(21);
+int vdprintf(int __fd, const char* __fmt, va_list __args) __printflike(2, 0) __INTRODUCED_IN(21);
 #else
 /*
  * Old versions of Android called these fdprintf and vfdprintf out of fears that the glibc names
@@ -153,111 +147,113 @@
  * Allow users to just use dprintf and vfdprintf on any version by renaming those calls to their
  * legacy equivalents if needed.
  */
-int dprintf(int, const char*, ...) __RENAME(fdprintf) __printflike(2, 3);
-int vdprintf(int, const char*, va_list) __RENAME(vfdprintf) __printflike(2, 0);
+int dprintf(int __fd, const char* __fmt, ...) __RENAME(fdprintf) __printflike(2, 3);
+int vdprintf(int __fd, const char* __fmt, va_list __args) __RENAME(vfdprintf) __printflike(2, 0);
 #endif
 
 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ < 201112L) || \
     (defined(__cplusplus) && __cplusplus <= 201103L)
-char* gets(char*) __attribute__((deprecated("gets is unsafe, use fgets instead")));
+char* gets(char* __buf) __attribute__((deprecated("gets is unsafe, use fgets instead")));
 #endif
-int sprintf(char*, const char*, ...)
+int sprintf(char* __s, const char* __fmt, ...)
     __printflike(2, 3) __warnattr_strict("sprintf is often misused; please use snprintf")
     __overloadable __RENAME_CLANG(sprintf);
-int vsprintf(char*, const char*, va_list)
+int vsprintf(char* __s, const char* __fmt, va_list __args)
     __overloadable __printflike(2, 0) __RENAME_CLANG(vsprintf)
     __warnattr_strict("vsprintf is often misused; please use vsnprintf");
-char* tmpnam(char*)
+char* tmpnam(char* __s)
     __warnattr("tempnam is unsafe, use mkstemp or tmpfile instead");
 #define P_tmpdir "/tmp/" /* deprecated */
-char* tempnam(const char*, const char*)
+char* tempnam(const char* __dir, const char* __prefix)
     __warnattr("tempnam is unsafe, use mkstemp or tmpfile instead");
 
-int rename(const char*, const char*);
-int renameat(int, const char*, int, const char*);
+int rename(const char* __old_path, const char* __new_path);
+int renameat(int __old_dir_fd, const char* __old_path, int __new_dir_fd, const char* __new_path);
 
-int fseek(FILE*, long, int);
-long ftell(FILE*);
+int fseek(FILE* __fp, long __offset, int __whence);
+long ftell(FILE* __fp);
 
 #if defined(__USE_FILE_OFFSET64)
-int fgetpos(FILE*, fpos_t*) __RENAME(fgetpos64) __INTRODUCED_IN(24);
-int fsetpos(FILE*, const fpos_t*) __RENAME(fsetpos64) __INTRODUCED_IN(24);
-int fseeko(FILE*, off_t, int) __RENAME(fseeko64) __INTRODUCED_IN(24);
-off_t ftello(FILE*) __RENAME(ftello64) __INTRODUCED_IN(24);
+int fgetpos(FILE* __fp, fpos_t* __pos) __RENAME(fgetpos64) __INTRODUCED_IN(24);
+int fsetpos(FILE* __fp, const fpos_t* __pos) __RENAME(fsetpos64) __INTRODUCED_IN(24);
+int fseeko(FILE* __fp, off_t __offset, int __whence) __RENAME(fseeko64) __INTRODUCED_IN(24);
+off_t ftello(FILE* __fp) __RENAME(ftello64) __INTRODUCED_IN(24);
 #  if defined(__USE_BSD)
-FILE* funopen(const void*,
-              int (*)(void*, char*, int),
-              int (*)(void*, const char*, int),
-              fpos_t (*)(void*, fpos_t, int),
-              int (*)(void*)) __RENAME(funopen64) __INTRODUCED_IN(24);
+FILE* funopen(const void* __cookie,
+              int (*__read_fn)(void*, char*, int),
+              int (*__write_fn)(void*, const char*, int),
+              fpos_t (*__seek_fn)(void*, fpos_t, int),
+              int (*__close_fn)(void*)) __RENAME(funopen64) __INTRODUCED_IN(24);
 #  endif
 #else
-int fgetpos(FILE*, fpos_t*);
-int fsetpos(FILE*, const fpos_t*);
-int fseeko(FILE*, off_t, int);
-off_t ftello(FILE*);
+int fgetpos(FILE* __fp, fpos_t* __pos);
+int fsetpos(FILE* __fp, const fpos_t* __pos);
+int fseeko(FILE* __fp, off_t __offset, int __whence);
+off_t ftello(FILE* __fp);
 #  if defined(__USE_BSD)
-FILE* funopen(const void*,
-              int (*)(void*, char*, int),
-              int (*)(void*, const char*, int),
-              fpos_t (*)(void*, fpos_t, int),
-              int (*)(void*));
+FILE* funopen(const void* __cookie,
+              int (*__read_fn)(void*, char*, int),
+              int (*__write_fn)(void*, const char*, int),
+              fpos_t (*__seek_fn)(void*, fpos_t, int),
+              int (*__close_fn)(void*));
 #  endif
 #endif
-int fgetpos64(FILE*, fpos64_t*) __INTRODUCED_IN(24);
-int fsetpos64(FILE*, const fpos64_t*) __INTRODUCED_IN(24);
-int fseeko64(FILE*, off64_t, int) __INTRODUCED_IN(24);
-off64_t ftello64(FILE*) __INTRODUCED_IN(24);
+int fgetpos64(FILE* __fp, fpos64_t* __pos) __INTRODUCED_IN(24);
+int fsetpos64(FILE* __fp, const fpos64_t* __pos) __INTRODUCED_IN(24);
+int fseeko64(FILE* __fp, off64_t __offset, int __whence) __INTRODUCED_IN(24);
+off64_t ftello64(FILE* __fp) __INTRODUCED_IN(24);
 #if defined(__USE_BSD)
-FILE* funopen64(const void*, int (*)(void*, char*, int), int (*)(void*, const char*, int),
-                fpos64_t (*)(void*, fpos64_t, int), int (*)(void*)) __INTRODUCED_IN(24);
+FILE* funopen64(const void* __cookie,
+                int (*__read_fn)(void*, char*, int),
+                int (*__write_fn)(void*, const char*, int),
+                fpos64_t (*__seek_fn)(void*, fpos64_t, int),
+                int (*__close_fn)(void*)) __INTRODUCED_IN(24);
 #endif
 
-FILE* fopen(const char*, const char*);
-FILE* fopen64(const char*, const char*) __INTRODUCED_IN(24);
-FILE* freopen(const char*, const char*, FILE*);
-FILE* freopen64(const char*, const char*, FILE*)
-  __INTRODUCED_IN(24);
+FILE* fopen(const char* __path, const char* __mode);
+FILE* fopen64(const char* __path, const char* __mode) __INTRODUCED_IN(24);
+FILE* freopen(const char* __path, const char* __mode, FILE* __fp);
+FILE* freopen64(const char* __path, const char* __mode, FILE* __fp) __INTRODUCED_IN(24);
 FILE* tmpfile(void);
 FILE* tmpfile64(void) __INTRODUCED_IN(24);
 
-int snprintf(char*, size_t, const char*, ...)
+int snprintf(char* __buf, size_t __size, const char* __fmt, ...)
     __printflike(3, 4) __overloadable __RENAME_CLANG(snprintf);
-int vfscanf(FILE*, const char*, va_list) __scanflike(2, 0);
-int vscanf(const char* , va_list) __scanflike(1, 0);
-int vsnprintf(char*, size_t, const char*, va_list)
+int vfscanf(FILE* __fp, const char* __fmt, va_list __args) __scanflike(2, 0);
+int vscanf(const char* __fmt , va_list __args) __scanflike(1, 0);
+int vsnprintf(char* __buf, size_t __size, const char* __fmt, va_list __args)
     __printflike(3, 0) __overloadable __RENAME_CLANG(vsnprintf);
-int vsscanf(const char*, const char*, va_list) __scanflike(2, 0);
+int vsscanf(const char* __s, const char* __fmt, va_list __args) __scanflike(2, 0);
 
 #define L_ctermid 1024 /* size for ctermid() */
-char* ctermid(char*) __INTRODUCED_IN(26);
+char* ctermid(char* __buf) __INTRODUCED_IN(26);
 
-FILE* fdopen(int, const char*);
-int fileno(FILE*);
-int pclose(FILE*);
-FILE* popen(const char*, const char*);
-void flockfile(FILE*);
-int ftrylockfile(FILE*);
-void funlockfile(FILE*);
-int getc_unlocked(FILE*);
+FILE* fdopen(int __fd, const char* __mode);
+int fileno(FILE* __fp);
+int pclose(FILE* __fp);
+FILE* popen(const char* __command, const char* __mode);
+void flockfile(FILE* __fp);
+int ftrylockfile(FILE* __fp);
+void funlockfile(FILE* __fp);
+int getc_unlocked(FILE* __fp);
 int getchar_unlocked(void);
-int putc_unlocked(int, FILE*);
-int putchar_unlocked(int);
+int putc_unlocked(int __ch, FILE* __fp);
+int putchar_unlocked(int __ch);
 
-FILE* fmemopen(void*, size_t, const char*) __INTRODUCED_IN(23);
-FILE* open_memstream(char**, size_t*) __INTRODUCED_IN(23);
+FILE* fmemopen(void* __buf, size_t __size, const char* __mode) __INTRODUCED_IN(23);
+FILE* open_memstream(char** __ptr, size_t* __size_ptr) __INTRODUCED_IN(23);
 
 #if defined(__USE_BSD) || defined(__BIONIC__) /* Historically bionic exposed these. */
-int  asprintf(char**, const char*, ...) __printflike(2, 3);
-char* fgetln(FILE*, size_t*);
-int fpurge(FILE*);
-void setbuffer(FILE*, char*, int);
-int setlinebuf(FILE*);
-int vasprintf(char**, const char*, va_list) __printflike(2, 0);
-void clearerr_unlocked(FILE*) __INTRODUCED_IN(23);
-int feof_unlocked(FILE*) __INTRODUCED_IN(23);
-int ferror_unlocked(FILE*) __INTRODUCED_IN(23);
-int fileno_unlocked(FILE*) __INTRODUCED_IN(24);
+int  asprintf(char** __s_ptr, const char* __fmt, ...) __printflike(2, 3);
+char* fgetln(FILE* __fp, size_t* __length_ptr);
+int fpurge(FILE* __fp);
+void setbuffer(FILE* __fp, char* __buf, int __size);
+int setlinebuf(FILE* __fp);
+int vasprintf(char** __s_ptr, const char* __fmt, va_list __args) __printflike(2, 0);
+void clearerr_unlocked(FILE* __fp) __INTRODUCED_IN(23);
+int feof_unlocked(FILE* __fp) __INTRODUCED_IN(23);
+int ferror_unlocked(FILE* __fp) __INTRODUCED_IN(23);
+int fileno_unlocked(FILE* __fp) __INTRODUCED_IN(24);
 #define fropen(cookie, fn) funopen(cookie, fn, 0, 0, 0)
 #define fwopen(cookie, fn) funopen(cookie, 0, fn, 0, 0)
 #endif /* __USE_BSD */
@@ -268,4 +264,4 @@
 
 __END_DECLS
 
-#endif /* _STDIO_H_ */
+#endif
diff --git a/libc/include/stdio_ext.h b/libc/include/stdio_ext.h
index 3c5abc3..66a3ab9 100644
--- a/libc/include/stdio_ext.h
+++ b/libc/include/stdio_ext.h
@@ -32,22 +32,23 @@
 #include <sys/cdefs.h>
 #include <stdio.h>
 
-#define FSETLOCKING_QUERY 0
-#define FSETLOCKING_INTERNAL 1
-#define FSETLOCKING_BYCALLER 2
 
 __BEGIN_DECLS
 
-size_t __fbufsize(FILE*) __INTRODUCED_IN(23);
-int __freadable(FILE*) __INTRODUCED_IN(23);
-int __freading(FILE*) __INTRODUCED_IN_FUTURE;
-int __fwritable(FILE*) __INTRODUCED_IN(23);
-int __fwriting(FILE*) __INTRODUCED_IN_FUTURE;
-int __flbf(FILE*) __INTRODUCED_IN(23);
-void __fpurge(FILE*) __INTRODUCED_IN(23);
-size_t __fpending(FILE*) __INTRODUCED_IN(23);
+size_t __fbufsize(FILE* __fp) __INTRODUCED_IN(23);
+int __freadable(FILE* __fp) __INTRODUCED_IN(23);
+int __freading(FILE* __fp) __INTRODUCED_IN_FUTURE;
+int __fwritable(FILE* __fp) __INTRODUCED_IN(23);
+int __fwriting(FILE* __fp) __INTRODUCED_IN_FUTURE;
+int __flbf(FILE* __fp) __INTRODUCED_IN(23);
+void __fpurge(FILE* __fp) __INTRODUCED_IN(23);
+size_t __fpending(FILE* __fp) __INTRODUCED_IN(23);
 void _flushlbf(void) __INTRODUCED_IN(23);
-int __fsetlocking(FILE*, int) __INTRODUCED_IN(23);
+
+#define FSETLOCKING_QUERY 0
+#define FSETLOCKING_INTERNAL 1
+#define FSETLOCKING_BYCALLER 2
+int __fsetlocking(FILE* __fp, int __type) __INTRODUCED_IN(23);
 
 __END_DECLS
 
diff --git a/libc/include/stdlib.h b/libc/include/stdlib.h
index 13c9d37..4182f2d 100644
--- a/libc/include/stdlib.h
+++ b/libc/include/stdlib.h
@@ -42,115 +42,114 @@
 #define EXIT_SUCCESS 0
 
 __noreturn void abort(void);
-__noreturn void exit(int);
-__noreturn void _Exit(int) __INTRODUCED_IN(21);
-int atexit(void (*)(void));
+__noreturn void exit(int __status);
+__noreturn void _Exit(int __status) __INTRODUCED_IN(21);
+int atexit(void (*__fn)(void));
 
-int at_quick_exit(void (*)(void)) __INTRODUCED_IN(21);
-void quick_exit(int) __noreturn __INTRODUCED_IN(21);
+int at_quick_exit(void (*__fn)(void)) __INTRODUCED_IN(21);
+void quick_exit(int __status) __noreturn __INTRODUCED_IN(21);
 
-char* getenv(const char*);
-int putenv(char*);
-int setenv(const char*, const char*, int);
-int unsetenv(const char*);
+char* getenv(const char* __name);
+int putenv(char* __assignment);
+int setenv(const char* __name, const char* __value, int __overwrite);
+int unsetenv(const char* __name);
 int clearenv(void);
 
-char* mkdtemp(char*);
-char* mktemp(char*) __attribute__((deprecated("mktemp is unsafe, use mkstemp or tmpfile instead")));
+char* mkdtemp(char* __template);
+char* mktemp(char* __template) __attribute__((deprecated("mktemp is unsafe, use mkstemp or tmpfile instead")));
 
-int mkostemp64(char*, int) __INTRODUCED_IN(23);
-int mkostemp(char*, int) __INTRODUCED_IN(23);
-int mkostemps64(char*, int, int) __INTRODUCED_IN(23);
-int mkostemps(char*, int, int) __INTRODUCED_IN(23);
-int mkstemp64(char*) __INTRODUCED_IN(21);
-int mkstemp(char*);
-int mkstemps64(char*, int) __INTRODUCED_IN(23);
-int mkstemps(char*, int);
+int mkostemp64(char* __template, int __flags) __INTRODUCED_IN(23);
+int mkostemp(char* __template, int __flags) __INTRODUCED_IN(23);
+int mkostemps64(char* __template, int __suffix_length, int __flags) __INTRODUCED_IN(23);
+int mkostemps(char* __template, int __suffix_length, int __flags) __INTRODUCED_IN(23);
+int mkstemp64(char* __template) __INTRODUCED_IN(21);
+int mkstemp(char* __template);
+int mkstemps64(char* __template, int __flags) __INTRODUCED_IN(23);
+int mkstemps(char* __template, int __flags);
 
-long strtol(const char *, char **, int);
-long long strtoll(const char *, char **, int);
-unsigned long strtoul(const char *, char **, int);
-unsigned long long strtoull(const char *, char **, int);
+long strtol(const char* __s, char** __end_ptr, int __base);
+long long strtoll(const char* __s, char** __end_ptr, int __base);
+unsigned long strtoul(const char* __s, char** __end_ptr, int __base);
+unsigned long long strtoull(const char* __s, char** __end_ptr, int __base);
 
-int posix_memalign(void** memptr, size_t alignment, size_t size) __INTRODUCED_IN(16);
+int posix_memalign(void** __memptr, size_t __alignment, size_t __size) __INTRODUCED_IN(16);
 
-double strtod(const char*, char**);
-long double strtold(const char*, char**) __INTRODUCED_IN(21);
+double strtod(const char* __s, char** __end_ptr);
+long double strtold(const char* __s, char** __end_ptr) __INTRODUCED_IN(21);
 
-unsigned long strtoul_l(const char*, char**, int, locale_t) __INTRODUCED_IN(26);
+unsigned long strtoul_l(const char* __s, char** __end_ptr, int __base, locale_t __l) __INTRODUCED_IN(26);
 
-int atoi(const char*) __attribute_pure__;
-long atol(const char*) __attribute_pure__;
-long long atoll(const char*) __attribute_pure__;
+int atoi(const char* __s) __attribute_pure__;
+long atol(const char* __s) __attribute_pure__;
+long long atoll(const char* __s) __attribute_pure__;
 
-char* realpath(const char* path, char* resolved);
-int system(const char *string);
+char* realpath(const char* __path, char* __resolved);
+int system(const char* __command);
 
-void* bsearch(const void* key, const void* base0, size_t nmemb, size_t size,
-              int (*compar)(const void*, const void*));
+void* bsearch(const void* __key, const void* __base, size_t __nmemb, size_t __size, int (*__comparator)(const void* __lhs, const void* __rhs));
 
-void qsort(void*, size_t, size_t, int (*)(const void*, const void*));
+void qsort(void* __base, size_t __nmemb, size_t __size, int (*__comparator)(const void* __lhs, const void* __rhs));
 
 uint32_t arc4random(void);
-uint32_t arc4random_uniform(uint32_t);
-void arc4random_buf(void*, size_t);
+uint32_t arc4random_uniform(uint32_t __upper_bound);
+void arc4random_buf(void* __buf, size_t __n);
 
 #define RAND_MAX 0x7fffffff
 
-int rand_r(unsigned int*) __INTRODUCED_IN(21);
+int rand_r(unsigned int* __seed_ptr) __INTRODUCED_IN(21);
 
 double drand48(void);
-double erand48(unsigned short[3]);
-long jrand48(unsigned short[3]);
-void lcong48(unsigned short[7]) __INTRODUCED_IN(23);
+double erand48(unsigned short __xsubi[3]);
+long jrand48(unsigned short __xsubi[3]);
+void lcong48(unsigned short __param[7]) __INTRODUCED_IN(23);
 long lrand48(void);
 long mrand48(void);
-long nrand48(unsigned short[3]);
-unsigned short* seed48(unsigned short[3]);
-void srand48(long);
+long nrand48(unsigned short __xsubi[3]);
+unsigned short* seed48(unsigned short __seed16v[3]);
+void srand48(long __seed);
 
-char* initstate(unsigned int, char*, size_t) __INTRODUCED_IN(21);
-char* setstate(char*) __INTRODUCED_IN(21);
+char* initstate(unsigned int __seed, char* __state, size_t __n) __INTRODUCED_IN(21);
+char* setstate(char* __state) __INTRODUCED_IN(21);
 
 int getpt(void);
-int posix_openpt(int) __INTRODUCED_IN(21);
-char* ptsname(int);
-int ptsname_r(int, char*, size_t);
-int unlockpt(int);
+int posix_openpt(int __flags) __INTRODUCED_IN(21);
+char* ptsname(int __fd);
+int ptsname_r(int __fd, char* __buf, size_t __n);
+int unlockpt(int __fd);
 
-int getsubopt(char**, char* const*, char**) __INTRODUCED_IN(26);
+int getsubopt(char** __option, char* const* __tokens, char** __value_ptr) __INTRODUCED_IN(26);
 
 typedef struct {
-    int  quot;
-    int  rem;
+  int quot;
+  int rem;
 } div_t;
 
-div_t div(int, int) __attribute_const__;
+div_t div(int __numerator, int __denominator) __attribute_const__;
 
 typedef struct {
-    long int  quot;
-    long int  rem;
+  long int quot;
+  long int rem;
 } ldiv_t;
 
-ldiv_t ldiv(long, long) __attribute_const__;
+ldiv_t ldiv(long __numerator, long __denominator) __attribute_const__;
 
 typedef struct {
-    long long int  quot;
-    long long int  rem;
+  long long int quot;
+  long long int rem;
 } lldiv_t;
 
-lldiv_t lldiv(long long, long long) __attribute_const__;
+lldiv_t lldiv(long long __numerator, long long __denominator) __attribute_const__;
 
 /* BSD compatibility. */
 const char* getprogname(void) __INTRODUCED_IN(21);
-void setprogname(const char*) __INTRODUCED_IN(21);
+void setprogname(const char* __name) __INTRODUCED_IN(21);
 
-int mblen(const char*, size_t) __INTRODUCED_IN(26) __VERSIONER_NO_GUARD;
-size_t mbstowcs(wchar_t*, const char*, size_t);
-int mbtowc(wchar_t*, const char*, size_t) __INTRODUCED_IN(21) __VERSIONER_NO_GUARD;
-int wctomb(char*, wchar_t) __INTRODUCED_IN(21) __VERSIONER_NO_GUARD;
+int mblen(const char* __s, size_t __n) __INTRODUCED_IN(26) __VERSIONER_NO_GUARD;
+size_t mbstowcs(wchar_t* __dst, const char* __src, size_t __n);
+int mbtowc(wchar_t* __wc_ptr, const char* __s, size_t __n) __INTRODUCED_IN(21) __VERSIONER_NO_GUARD;
+int wctomb(char* __dst, wchar_t __wc) __INTRODUCED_IN(21) __VERSIONER_NO_GUARD;
 
-size_t wcstombs(char*, const wchar_t*, size_t);
+size_t wcstombs(char* __dst, const wchar_t* __src, size_t __n);
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
 size_t __ctype_get_mb_cur_max(void) __INTRODUCED_IN(21);
@@ -169,28 +168,28 @@
 #endif
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
-float strtof(const char*, char**) __INTRODUCED_IN(21);
-double atof(const char*) __attribute_pure__ __INTRODUCED_IN(21);
-int abs(int) __attribute_const__ __INTRODUCED_IN(21);
-long labs(long) __attribute_const__ __INTRODUCED_IN(21);
-long long llabs(long long) __attribute_const__ __INTRODUCED_IN(21);
+float strtof(const char* __s, char** __end_ptr) __INTRODUCED_IN(21);
+double atof(const char* __s) __attribute_pure__ __INTRODUCED_IN(21);
+int abs(int __x) __attribute_const__ __INTRODUCED_IN(21);
+long labs(long __x) __attribute_const__ __INTRODUCED_IN(21);
+long long llabs(long long __x) __attribute_const__ __INTRODUCED_IN(21);
 int rand(void) __INTRODUCED_IN(21);
-void srand(unsigned int) __INTRODUCED_IN(21);
+void srand(unsigned int __seed) __INTRODUCED_IN(21);
 long random(void) __INTRODUCED_IN(21);
-void srandom(unsigned int) __INTRODUCED_IN(21);
-int grantpt(int) __INTRODUCED_IN(21);
+void srandom(unsigned int __seed) __INTRODUCED_IN(21);
+int grantpt(int __fd) __INTRODUCED_IN(21);
 
-long long strtoll_l(const char*, char**, int, locale_t) __INTRODUCED_IN(21);
-unsigned long long strtoull_l(const char*, char**, int, locale_t) __INTRODUCED_IN(21);
-long double strtold_l(const char*, char**, locale_t) __INTRODUCED_IN(21);
+long long strtoll_l(const char* __s, char** __end_ptr, int __base, locale_t __l) __INTRODUCED_IN(21);
+unsigned long long strtoull_l(const char* __s, char** __end_ptr, int __base, locale_t __l) __INTRODUCED_IN(21);
+long double strtold_l(const char* __s, char** __end_ptr, locale_t __l) __INTRODUCED_IN(21);
 #else
 // Implemented as static inlines before 21.
 #endif
 
 #if __ANDROID_API__ >= __ANDROID_API_O__
-double strtod_l(const char*, char**, locale_t) __INTRODUCED_IN(26);
-float strtof_l(const char*, char**, locale_t) __INTRODUCED_IN(26);
-long strtol_l(const char*, char**, int, locale_t) __INTRODUCED_IN(26);
+double strtod_l(const char* __s, char** __end_ptr, locale_t __l) __INTRODUCED_IN(26);
+float strtof_l(const char* __s, char** __end_ptr, locale_t __l) __INTRODUCED_IN(26);
+long strtol_l(const char* __s, char** __end_ptr, int, locale_t __l) __INTRODUCED_IN(26);
 #else
 // Implemented as static inlines before 26.
 #endif
diff --git a/libc/include/string.h b/libc/include/string.h
index 631b3dd..164146d 100644
--- a/libc/include/string.h
+++ b/libc/include/string.h
@@ -58,8 +58,11 @@
 char* __strchr_chk(const char*, int, size_t) __INTRODUCED_IN(18);
 #if defined(__USE_GNU)
 #if defined(__cplusplus)
+/* The versioner doesn't handle C++ blocks yet, so manually guarded. */
+#if __ANDROID_API__ >= 24
 extern "C++" char* strchrnul(char*, int) __RENAME(strchrnul) __attribute_pure__ __INTRODUCED_IN(24);
 extern "C++" const char* strchrnul(const char*, int) __RENAME(strchrnul) __attribute_pure__ __INTRODUCED_IN(24);
+#endif  /* __ANDROID_API__ >= 24 */
 #else
 char* strchrnul(const char*, int) __attribute_pure__ __INTRODUCED_IN(24);
 #endif
@@ -125,8 +128,11 @@
  * It doesn't modify its argument, and in C++ it's const-correct.
  */
 #if defined(__cplusplus)
+/* The versioner doesn't handle C++ blocks yet, so manually guarded. */
+#if __ANDROID_API__ >= 23
 extern "C++" char* basename(char*) __RENAME(__gnu_basename) __INTRODUCED_IN(23);
 extern "C++" const char* basename(const char*) __RENAME(__gnu_basename) __INTRODUCED_IN(23);
+#endif  /* __ANDROID_API__ >= 23 */
 #else
 char* basename(const char*) __RENAME(__gnu_basename) __INTRODUCED_IN(23);
 #endif
diff --git a/libc/include/strings.h b/libc/include/strings.h
index 11f3213..c2e0a5e 100644
--- a/libc/include/strings.h
+++ b/libc/include/strings.h
@@ -55,11 +55,11 @@
 #endif
 
 #if !defined(__i386__) || __ANDROID_API__ >= __ANDROID_API_J_MR2__
-int ffs(int) __INTRODUCED_IN_X86(18);
+int ffs(int __i) __INTRODUCED_IN_X86(18);
 #endif
 
 __END_DECLS
 
 #include <android/legacy_strings_inlines.h>
 
-#endif /* !defined(_STRINGS_H_) */
+#endif
diff --git a/libc/include/sys/_system_properties.h b/libc/include/sys/_system_properties.h
index f8dbd33..67beb9a 100644
--- a/libc/include/sys/_system_properties.h
+++ b/libc/include/sys/_system_properties.h
@@ -61,14 +61,14 @@
 ** Map the property area from the specified filename.  This
 ** method is for testing only.
 */
-int __system_property_set_filename(const char *filename);
+int __system_property_set_filename(const char* __filename);
 
 /*
 ** Initialize the area to be used to store properties.  Can
 ** only be done by a single process that has write access to
 ** the property area.
 */
-int __system_property_area_init();
+int __system_property_area_init(void);
 
 /* Read the global serial number of the system properties
 **
@@ -92,7 +92,7 @@
 **
 ** Returns the serial number on success, -1 on error.
 */
-uint32_t __system_property_area_serial();
+uint32_t __system_property_area_serial(void);
 
 /* Add a new system property.  Can only be done by a single
 ** process that has write access to the property area, and
@@ -102,7 +102,7 @@
 **
 ** Returns 0 on success, -1 if the property area is full.
 */
-int __system_property_add(const char *name, unsigned int namelen, const char *value, unsigned int valuelen);
+int __system_property_add(const char* __name, unsigned int __name_length, const char* __value, unsigned int __value_length);
 
 /* Update the value of a system property returned by
 ** __system_property_find.  Can only be done by a single process
@@ -112,14 +112,14 @@
 **
 ** Returns 0 on success, -1 if the parameters are incorrect.
 */
-int __system_property_update(prop_info *pi, const char *value, unsigned int len);
+int __system_property_update(prop_info* __pi, const char* __value, unsigned int __value_length);
 
 /* Read the serial number of a system property returned by
 ** __system_property_find.
 **
 ** Returns the serial number on success, -1 on error.
 */
-uint32_t __system_property_serial(const prop_info* pi);
+uint32_t __system_property_serial(const prop_info* __pi);
 
 /* Initialize the system properties area in read only mode.
  * Should be done by all processes that need to read system
@@ -127,10 +127,10 @@
  *
  * Returns 0 on success, -1 otherwise.
  */
-int __system_properties_init();
+int __system_properties_init(void);
 
 /* Deprecated: use __system_property_wait instead. */
-uint32_t __system_property_wait_any(uint32_t old_serial);
+uint32_t __system_property_wait_any(uint32_t __old_serial);
 
 __END_DECLS
 
diff --git a/libc/include/sys/auxv.h b/libc/include/sys/auxv.h
index ab5a39d..9251390 100644
--- a/libc/include/sys/auxv.h
+++ b/libc/include/sys/auxv.h
@@ -35,8 +35,8 @@
 
 __BEGIN_DECLS
 
-unsigned long int getauxval(unsigned long int type) __INTRODUCED_IN(18);
+unsigned long int getauxval(unsigned long int __type) __INTRODUCED_IN(18);
 
 __END_DECLS
 
-#endif /* _SYS_AUXV_H_ */
+#endif
diff --git a/libc/include/sys/cachectl.h b/libc/include/sys/cachectl.h
index 5b20c19..9235327 100644
--- a/libc/include/sys/cachectl.h
+++ b/libc/include/sys/cachectl.h
@@ -34,4 +34,4 @@
 #include <asm/cachectl.h>
 #endif
 
-#endif /* sys/cachectl.h */
+#endif
diff --git a/libc/include/sys/capability.h b/libc/include/sys/capability.h
index b9a40b3..637c844 100644
--- a/libc/include/sys/capability.h
+++ b/libc/include/sys/capability.h
@@ -34,9 +34,9 @@
 
 __BEGIN_DECLS
 
-int capget(cap_user_header_t hdrp, cap_user_data_t datap);
-int capset(cap_user_header_t hdrp, const cap_user_data_t datap);
+int capget(cap_user_header_t __hdr_ptr, cap_user_data_t __data_ptr);
+int capset(cap_user_header_t __hdr_ptr, const cap_user_data_t __data_ptr);
 
 __END_DECLS
 
-#endif /* _BIONIC_SYS_CAPABILITY_H */
+#endif
diff --git a/libc/include/sys/cdefs.h b/libc/include/sys/cdefs.h
index 9541520..71d8426 100644
--- a/libc/include/sys/cdefs.h
+++ b/libc/include/sys/cdefs.h
@@ -239,7 +239,8 @@
 
 #define __BIONIC_FORTIFY_UNKNOWN_SIZE ((size_t) -1)
 
-#if defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0 && defined(__OPTIMIZE__) && __OPTIMIZE__ > 0
+#if defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0 && \
+      (defined(__clang__) || (defined(__OPTIMIZE__) && __OPTIMIZE__ > 0))
 #  define __BIONIC_FORTIFY 1
 #  if _FORTIFY_SOURCE == 2
 #    define __bos_level 1
@@ -281,8 +282,7 @@
 #define __pass_object_size __pass_object_size_n(__bos_level)
 #define __pass_object_size0 __pass_object_size_n(0)
 
-/* FIXME: This should be __BIONIC_FORTIFY, but we don't enable FORTIFY in -O0. */
-#if (defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0) || defined(__BIONIC_DECLARE_FORTIFY_HELPERS)
+#if defined(__BIONIC_FORTIFY) || defined(__BIONIC_DECLARE_FORTIFY_HELPERS)
 #  define __BIONIC_INCLUDE_FORTIFY_HEADERS 1
 #endif
 
diff --git a/libc/include/sys/endian.h b/libc/include/sys/endian.h
index de172fe..799a6f2 100644
--- a/libc/include/sys/endian.h
+++ b/libc/include/sys/endian.h
@@ -49,10 +49,10 @@
 
 /* glibc compatibility. */
 __BEGIN_DECLS
-uint32_t htonl(uint32_t) __attribute_const__ __INTRODUCED_IN(21);
-uint16_t htons(uint16_t) __attribute_const__ __INTRODUCED_IN(21);
-uint32_t ntohl(uint32_t) __attribute_const__ __INTRODUCED_IN(21);
-uint16_t ntohs(uint16_t) __attribute_const__ __INTRODUCED_IN(21);
+uint32_t htonl(uint32_t __x) __attribute_const__ __INTRODUCED_IN(21);
+uint16_t htons(uint16_t __x) __attribute_const__ __INTRODUCED_IN(21);
+uint32_t ntohl(uint32_t __x) __attribute_const__ __INTRODUCED_IN(21);
+uint16_t ntohs(uint16_t __x) __attribute_const__ __INTRODUCED_IN(21);
 __END_DECLS
 
 #define htonl(x) __swap32(x)
@@ -103,4 +103,4 @@
 #define le64toh(x) htole64(x)
 #endif /* __USE_BSD */
 
-#endif /* _SYS_ENDIAN_H_ */
+#endif
diff --git a/libc/include/sys/epoll.h b/libc/include/sys/epoll.h
index fcdab43..6ecd93f 100644
--- a/libc/include/sys/epoll.h
+++ b/libc/include/sys/epoll.h
@@ -53,8 +53,8 @@
 #endif
 ;
 
-int epoll_create(int);
-int epoll_create1(int) __INTRODUCED_IN(21);
+int epoll_create(int __size);
+int epoll_create1(int __flags) __INTRODUCED_IN(21);
 
 /*
  * Some third-party code uses the existence of EPOLL_CLOEXEC to detect the
@@ -71,10 +71,10 @@
 #undef EPOLL_CLOEXEC
 #endif
 
-int epoll_ctl(int, int, int, struct epoll_event*);
-int epoll_wait(int, struct epoll_event*, int, int);
-int epoll_pwait(int, struct epoll_event*, int, int, const sigset_t*) __INTRODUCED_IN(21);
+int epoll_ctl(int __epoll_fd, int __op, int __fd, struct epoll_event* __event);
+int epoll_wait(int __epoll_fd, struct epoll_event* __events, int __event_count, int __timeout_ms);
+int epoll_pwait(int __epoll_fd, struct epoll_event* __events, int __event_count, int __timeout_ms, const sigset_t* __mask) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif  /* _SYS_EPOLL_H_ */
+#endif
diff --git a/libc/include/sys/eventfd.h b/libc/include/sys/eventfd.h
index 6b9749a..3cfb5e7 100644
--- a/libc/include/sys/eventfd.h
+++ b/libc/include/sys/eventfd.h
@@ -37,14 +37,13 @@
 #define EFD_CLOEXEC O_CLOEXEC
 #define EFD_NONBLOCK O_NONBLOCK
 
-/* type of event counter */
 typedef uint64_t eventfd_t;
 
-int eventfd(unsigned int initial_value, int flags);
+int eventfd(unsigned int __initial_value, int __flags);
 
-int eventfd_read(int fd, eventfd_t* value);
-int eventfd_write(int fd, eventfd_t value);
+int eventfd_read(int __fd, eventfd_t* __value);
+int eventfd_write(int __fd, eventfd_t __value);
 
 __END_DECLS
 
-#endif /* _SYS_EVENTFD_H */
+#endif
diff --git a/libc/include/sys/file.h b/libc/include/sys/file.h
index f414d34..a420021 100644
--- a/libc/include/sys/file.h
+++ b/libc/include/sys/file.h
@@ -36,8 +36,8 @@
 
 __BEGIN_DECLS
 
-int flock(int, int);
+int flock(int __fd, int __op);
 
 __END_DECLS
 
-#endif /* _SYS_FILE_H_ */
+#endif
diff --git a/libc/include/sys/fsuid.h b/libc/include/sys/fsuid.h
index e4d9ebc..bb7a58d 100644
--- a/libc/include/sys/fsuid.h
+++ b/libc/include/sys/fsuid.h
@@ -34,9 +34,9 @@
 
 __BEGIN_DECLS
 
-int setfsuid(uid_t) __INTRODUCED_IN(21);
-int setfsgid(gid_t) __INTRODUCED_IN(21);
+int setfsuid(uid_t __uid) __INTRODUCED_IN(21);
+int setfsgid(gid_t __gid) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif /* _SYS_FSUID_H_ */
+#endif
diff --git a/libc/include/sys/inotify.h b/libc/include/sys/inotify.h
index 98f7198..32e16d9 100644
--- a/libc/include/sys/inotify.h
+++ b/libc/include/sys/inotify.h
@@ -54,10 +54,10 @@
 #endif
 
 int inotify_init(void);
-int inotify_init1(int) __INTRODUCED_IN(21);
-int inotify_add_watch(int, const char*, uint32_t);
-int inotify_rm_watch(int, uint32_t);
+int inotify_init1(int __flags) __INTRODUCED_IN(21);
+int inotify_add_watch(int __fd, const char* __path, uint32_t __mask);
+int inotify_rm_watch(int __fd, uint32_t __watch_descriptor);
 
 __END_DECLS
 
-#endif /* _SYS_INOTIFY_H_ */
+#endif
diff --git a/libc/include/sys/ioctl.h b/libc/include/sys/ioctl.h
index efbcb0c..76dc1ff 100644
--- a/libc/include/sys/ioctl.h
+++ b/libc/include/sys/ioctl.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_IOCTL_H_
 #define _SYS_IOCTL_H_
 
@@ -41,4 +42,4 @@
 
 #include <bits/ioctl.h>
 
-#endif /* _SYS_IOCTL_H_ */
+#endif
diff --git a/libc/include/sys/ipc.h b/libc/include/sys/ipc.h
index 3d6c45f..dee7c8a 100644
--- a/libc/include/sys/ipc.h
+++ b/libc/include/sys/ipc.h
@@ -42,8 +42,8 @@
 
 __BEGIN_DECLS
 
-key_t ftok(const char* path, int id);
+key_t ftok(const char* __path, int __id);
 
 __END_DECLS
 
-#endif /* _SYS_IPC_H */
+#endif
diff --git a/libc/include/sys/klog.h b/libc/include/sys/klog.h
index 47eb3a4..ed746fc 100644
--- a/libc/include/sys/klog.h
+++ b/libc/include/sys/klog.h
@@ -46,8 +46,8 @@
 #define KLOG_SIZE_UNREAD   9
 #define KLOG_SIZE_BUFFER   10
 
-int klogctl(int, char *, int);
+int klogctl(int __type, char* __buf, int __buf_size);
 
 __END_DECLS
 
-#endif /* _SYS_KLOG_H_ */
+#endif
diff --git a/libc/include/sys/mman.h b/libc/include/sys/mman.h
index 1440dc6..1e752c4 100644
--- a/libc/include/sys/mman.h
+++ b/libc/include/sys/mman.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_MMAN_H_
 #define _SYS_MMAN_H_
 
@@ -44,27 +45,27 @@
 #define MREMAP_FIXED    2
 
 #if defined(__USE_FILE_OFFSET64)
-void* mmap(void*, size_t, int, int, int, off_t) __RENAME(mmap64) __INTRODUCED_IN(21);
+void* mmap(void* __addr, size_t __size, int __prot, int __flags, int __fd, off_t __offset) __RENAME(mmap64) __INTRODUCED_IN(21);
 #else
-void* mmap(void*, size_t, int, int, int, off_t);
+void* mmap(void* __addr, size_t __size, int __prot, int __flags, int __fd, off_t __offset);
 #endif
 
-void* mmap64(void*, size_t, int, int, int, off64_t) __INTRODUCED_IN(21);
+void* mmap64(void* __addr, size_t __size, int __prot, int __flags, int __fd, off64_t __offset) __INTRODUCED_IN(21);
 
-int munmap(void*, size_t);
-int msync(void*, size_t, int);
-int mprotect(void*, size_t, int);
-void* mremap(void*, size_t, size_t, int, ...);
+int munmap(void* __addr, size_t __size);
+int msync(void* __addr, size_t __size, int __flags);
+int mprotect(void* __addr, size_t __size, int __prot);
+void* mremap(void* __old_addr, size_t __old_size, size_t __new_size, int __flags, ...);
 
-int mlockall(int) __INTRODUCED_IN(17);
+int mlockall(int __flags) __INTRODUCED_IN(17);
 int munlockall(void) __INTRODUCED_IN(17);
 
-int mlock(const void*, size_t);
-int munlock(const void*, size_t);
+int mlock(const void* __addr, size_t __size);
+int munlock(const void* __addr, size_t __size);
 
-int mincore(void*, size_t, unsigned char*);
+int mincore(void* __addr, size_t __size, unsigned char* __vector);
 
-int madvise(void*, size_t, int);
+int madvise(void* __addr, size_t __size, int __advice);
 
 #if __ANDROID_API__ >= __ANDROID_API_M__
 /*
@@ -81,8 +82,8 @@
 #define POSIX_MADV_WILLNEED   MADV_WILLNEED
 #define POSIX_MADV_DONTNEED   MADV_DONTNEED
 #endif
-int posix_madvise(void*, size_t, int) __INTRODUCED_IN(23);
+int posix_madvise(void* __addr, size_t __size, int __advice) __INTRODUCED_IN(23);
 
 __END_DECLS
 
-#endif /* _SYS_MMAN_H_ */
+#endif
diff --git a/libc/include/sys/mount.h b/libc/include/sys/mount.h
index 26c0e0f..c0c084b 100644
--- a/libc/include/sys/mount.h
+++ b/libc/include/sys/mount.h
@@ -41,10 +41,10 @@
 #define MNT_EXPIRE 4
 #define UMOUNT_NOFOLLOW 8
 
-int mount(const char*, const char*, const char*, unsigned long, const void*);
-int umount(const char*);
-int umount2(const char*, int);
+int mount(const char* __source, const char* __target, const char* __fs_type, unsigned long __flags, const void* __data);
+int umount(const char* __target);
+int umount2(const char* __target, int __flags);
 
 __END_DECLS
 
-#endif /* _SYS_MOUNT_H */
+#endif
diff --git a/libc/include/sys/msg.h b/libc/include/sys/msg.h
index ced5a3e..0273499 100644
--- a/libc/include/sys/msg.h
+++ b/libc/include/sys/msg.h
@@ -41,11 +41,11 @@
 typedef __kernel_ulong_t msgqnum_t;
 typedef __kernel_ulong_t msglen_t;
 
-int msgctl(int, int, struct msqid_ds*) __INTRODUCED_IN(26);
-int msgget(key_t, int) __INTRODUCED_IN(26);
-ssize_t msgrcv(int, void*, size_t, long, int) __INTRODUCED_IN(26);
-int msgsnd(int, const void*, size_t, int) __INTRODUCED_IN(26);
+int msgctl(int __msg_id, int __cmd, struct msqid_ds* __buf) __INTRODUCED_IN(26);
+int msgget(key_t __key, int __flags) __INTRODUCED_IN(26);
+ssize_t msgrcv(int __msg_id, void* __msgbuf_ptr, size_t __size, long __type, int __flags) __INTRODUCED_IN(26);
+int msgsnd(int __msg_id, const void* __msgbuf_ptr, size_t __size, int __flags) __INTRODUCED_IN(26);
 
 __END_DECLS
 
-#endif /* _SYS_MSG_H_ */
+#endif
diff --git a/libc/include/sys/param.h b/libc/include/sys/param.h
index d3686e0..ec50da2 100644
--- a/libc/include/sys/param.h
+++ b/libc/include/sys/param.h
@@ -49,4 +49,4 @@
 #define MIN(a,b) (((a)<(b))?(a):(b))
 #define MAX(a,b) (((a)>(b))?(a):(b))
 
-#endif /* _SYS_PARAM_H_ */
+#endif
diff --git a/libc/include/sys/personality.h b/libc/include/sys/personality.h
index 6f3a3c9..51b5cd7 100644
--- a/libc/include/sys/personality.h
+++ b/libc/include/sys/personality.h
@@ -34,8 +34,8 @@
 
 __BEGIN_DECLS
 
-int personality(unsigned int persona) __INTRODUCED_IN(15);
+int personality(unsigned int __persona) __INTRODUCED_IN(15);
 
 __END_DECLS
 
-#endif /* _SYS_PERSONALITY_H_ */
+#endif
diff --git a/libc/include/sys/prctl.h b/libc/include/sys/prctl.h
index 742ed57..64f5954 100644
--- a/libc/include/sys/prctl.h
+++ b/libc/include/sys/prctl.h
@@ -35,8 +35,8 @@
 
 __BEGIN_DECLS
 
-int prctl(int option, ...);
+int prctl(int __option, ...);
 
 __END_DECLS
 
-#endif /* _SYS_PRCTL_H */
+#endif
diff --git a/libc/include/sys/procfs.h b/libc/include/sys/procfs.h
index eff39e2..75a1e98 100644
--- a/libc/include/sys/procfs.h
+++ b/libc/include/sys/procfs.h
@@ -59,4 +59,4 @@
 
 __END_DECLS
 
-#endif /* _SYS_PROCFS_H_ */
+#endif
diff --git a/libc/include/sys/ptrace.h b/libc/include/sys/ptrace.h
index 4b881e7..022fc3a 100644
--- a/libc/include/sys/ptrace.h
+++ b/libc/include/sys/ptrace.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_PTRACE_H_
 #define _SYS_PTRACE_H_
 
@@ -58,8 +59,8 @@
 #define PT_GETSIGINFO PTRACE_GETSIGINFO
 #define PT_SETSIGINFO PTRACE_SETSIGINFO
 
-long ptrace(int, ...);
+long ptrace(int __request, ...);
 
 __END_DECLS
 
-#endif /* _SYS_PTRACE_H_ */
+#endif
diff --git a/libc/include/sys/quota.h b/libc/include/sys/quota.h
index 51f7675..157c2d9 100644
--- a/libc/include/sys/quota.h
+++ b/libc/include/sys/quota.h
@@ -40,7 +40,7 @@
 
 __BEGIN_DECLS
 
-int quotactl(int, const char*, int, char*) __INTRODUCED_IN(26);
+int quotactl(int __cmd, const char* __special, int __id, char* __addr) __INTRODUCED_IN(26);
 
 __END_DECLS
 
diff --git a/libc/include/sys/reboot.h b/libc/include/sys/reboot.h
index df4739e..c0c4860 100644
--- a/libc/include/sys/reboot.h
+++ b/libc/include/sys/reboot.h
@@ -42,8 +42,8 @@
 #define RB_DISABLE_CAD  LINUX_REBOOT_CMD_CAD_OFF
 #define RB_POWER_OFF    LINUX_REBOOT_CMD_POWER_OFF
 
-int reboot(int reboot_type);
+int reboot(int __cmd);
 
 __END_DECLS
 
-#endif /* _SYS_REBOOT_H_ */
+#endif
diff --git a/libc/include/sys/reg.h b/libc/include/sys/reg.h
index 1066b6d..6c496ba 100644
--- a/libc/include/sys/reg.h
+++ b/libc/include/sys/reg.h
@@ -83,4 +83,4 @@
 
 #endif
 
-#endif /* _SYS_REG_H_ */
+#endif
diff --git a/libc/include/sys/resource.h b/libc/include/sys/resource.h
index 7c43ca3..9181125 100644
--- a/libc/include/sys/resource.h
+++ b/libc/include/sys/resource.h
@@ -42,21 +42,20 @@
 
 typedef unsigned long rlim_t;
 
-int getrlimit(int, struct rlimit*);
-int setrlimit(int, const struct rlimit*);
+int getrlimit(int __resource, struct rlimit* __limit);
+int setrlimit(int __resource, const struct rlimit* __limit);
 
-int getrlimit64(int, struct rlimit64*) __INTRODUCED_IN(21);
-int setrlimit64(int, const struct rlimit64*) __INTRODUCED_IN(21);
+int getrlimit64(int __resource, struct rlimit64* __limit) __INTRODUCED_IN(21);
+int setrlimit64(int __resource, const struct rlimit64* __limit) __INTRODUCED_IN(21);
 
-int getpriority(int, id_t);
-int setpriority(int, id_t, int);
+int getpriority(int __which, id_t __who);
+int setpriority(int __which, id_t __who, int __priority);
 
-int getrusage(int, struct rusage*);
+int getrusage(int __who, struct rusage* __usage);
 
-int prlimit(pid_t, int, const struct rlimit*, struct rlimit*) __INTRODUCED_IN_32(24)
-  __INTRODUCED_IN_64(21);
-int prlimit64(pid_t, int, const struct rlimit64*, struct rlimit64*) __INTRODUCED_IN(21);
+int prlimit(pid_t __pid, int __resource, const struct rlimit* __new_limit, struct rlimit* __old_limit) __INTRODUCED_IN_32(24) __INTRODUCED_IN_64(21);
+int prlimit64(pid_t __pid, int __resource, const struct rlimit64* __new_limit, struct rlimit64* __old_limit) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif /* _SYS_RESOURCE_H_ */
+#endif
diff --git a/libc/include/sys/select.h b/libc/include/sys/select.h
index 40bd32e..e919188 100644
--- a/libc/include/sys/select.h
+++ b/libc/include/sys/select.h
@@ -72,9 +72,9 @@
 #define FD_ISSET(fd, set) ((__FDS_BITS(set)[__FDELT(fd)] & __FDMASK(fd)) != 0)
 #endif /* defined(__BIONIC_FORTIFY) && __ANDROID_API >= 21 */
 
-int select(int, fd_set*, fd_set*, fd_set*, struct timeval*);
-int pselect(int, fd_set*, fd_set*, fd_set*, const struct timespec*, const sigset_t*);
+int select(int __fd_count, fd_set* __read_fds, fd_set* __write_fds, fd_set* __exception_fds, struct timeval* __timeout);
+int pselect(int __fd_count, fd_set* __read_fds, fd_set* __write_fds, fd_set* __exception_fds, const struct timespec* __timeout, const sigset_t* __mask);
 
 __END_DECLS
 
-#endif /* _SYS_SELECT_H_ */
+#endif
diff --git a/libc/include/sys/sem.h b/libc/include/sys/sem.h
index be0e22d..cd62242 100644
--- a/libc/include/sys/sem.h
+++ b/libc/include/sys/sem.h
@@ -51,12 +51,12 @@
   void* __pad;
 };
 
-int semctl(int, int, int, ...) __INTRODUCED_IN(26);
-int semget(key_t, int, int) __INTRODUCED_IN(26);
-int semop(int, struct sembuf*, size_t) __INTRODUCED_IN(26);
+int semctl(int __sem_id, int __sem_num, int __cmd, ...) __INTRODUCED_IN(26);
+int semget(key_t __key, int __sem_count, int __flags) __INTRODUCED_IN(26);
+int semop(int __sem_id, struct sembuf* __ops, size_t __op_count) __INTRODUCED_IN(26);
 
 #if defined(__USE_GNU)
-int semtimedop(int, struct sembuf*, size_t, const struct timespec*) __INTRODUCED_IN(26);
+int semtimedop(int __sem_id, struct sembuf* __ops, size_t __op_count, const struct timespec* __timeout) __INTRODUCED_IN(26);
 #endif
 
 __END_DECLS
diff --git a/libc/include/sys/sendfile.h b/libc/include/sys/sendfile.h
index 43b334c..ecdb76c 100644
--- a/libc/include/sys/sendfile.h
+++ b/libc/include/sys/sendfile.h
@@ -35,12 +35,12 @@
 __BEGIN_DECLS
 
 #if defined(__USE_FILE_OFFSET64)
-ssize_t sendfile(int out_fd, int in_fd, off_t* offset, size_t count) __RENAME(sendfile64) __INTRODUCED_IN(21);
+ssize_t sendfile(int __out_fd, int __in_fd, off_t* __offset, size_t __count) __RENAME(sendfile64) __INTRODUCED_IN(21);
 #else
-ssize_t sendfile(int out_fd, int in_fd, off_t* offset, size_t count);
+ssize_t sendfile(int __out_fd, int __in_fd, off_t* __offset, size_t __count);
 #endif
-ssize_t sendfile64(int out_fd, int in_fd, off64_t* offset, size_t count) __INTRODUCED_IN(21);
+ssize_t sendfile64(int __out_fd, int __in_fd, off64_t* __offset, size_t __count) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif /* _SYS_SENDFILE_H_ */
+#endif
diff --git a/libc/include/sys/shm.h b/libc/include/sys/shm.h
index ccd3b36..4723eba 100644
--- a/libc/include/sys/shm.h
+++ b/libc/include/sys/shm.h
@@ -42,10 +42,10 @@
 
 typedef unsigned long shmatt_t;
 
-void* shmat(int, const void*, int) __INTRODUCED_IN(26);
-int shmctl(int, int, struct shmid_ds*) __INTRODUCED_IN(26);
-int shmdt(const void*) __INTRODUCED_IN(26);
-int shmget(key_t, size_t, int) __INTRODUCED_IN(26);
+void* shmat(int __shm_id, const void* __addr, int __flags) __INTRODUCED_IN(26);
+int shmctl(int __shm_id, int __cmd, struct shmid_ds* __buf) __INTRODUCED_IN(26);
+int shmdt(const void* __addr) __INTRODUCED_IN(26);
+int shmget(key_t __key, size_t __size, int __flags) __INTRODUCED_IN(26);
 
 __END_DECLS
 
diff --git a/libc/include/sys/signalfd.h b/libc/include/sys/signalfd.h
index 1e4d464..315622c 100644
--- a/libc/include/sys/signalfd.h
+++ b/libc/include/sys/signalfd.h
@@ -36,8 +36,8 @@
 
 __BEGIN_DECLS
 
-int signalfd(int fd, const sigset_t* mask, int flags) __INTRODUCED_IN(18);
+int signalfd(int __fd, const sigset_t* __mask, int __flags) __INTRODUCED_IN(18);
 
 __END_DECLS
 
-#endif /* _SYS_SIGNALFD_H */
+#endif
diff --git a/libc/include/sys/socket.h b/libc/include/sys/socket.h
index 6875d7f..ed851a2 100644
--- a/libc/include/sys/socket.h
+++ b/libc/include/sys/socket.h
@@ -115,7 +115,7 @@
 #define CMSG_OK(mhdr, cmsg) ((cmsg)->cmsg_len >= sizeof(struct cmsghdr) &&   (cmsg)->cmsg_len <= (unsigned long)   ((mhdr)->msg_controllen -   ((char*)(cmsg) - (char*)(mhdr)->msg_control)))
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
-struct cmsghdr* __cmsg_nxthdr(struct msghdr*, struct cmsghdr*) __INTRODUCED_IN(21);
+struct cmsghdr* __cmsg_nxthdr(struct msghdr* __msg, struct cmsghdr* __cmsg) __INTRODUCED_IN(21);
 #else
 /* TODO(danalbert): Move this into libandroid_support. */
 static inline struct cmsghdr* __cmsg_nxthdr(struct msghdr* msg, struct cmsghdr* cmsg) {
@@ -299,31 +299,30 @@
 # define __socketcall extern
 #endif
 
-__socketcall int accept(int, struct sockaddr*, socklen_t*);
-__socketcall int accept4(int, struct sockaddr*, socklen_t*, int) __INTRODUCED_IN(21);
-__socketcall int bind(int, const struct sockaddr*, socklen_t);
-__socketcall int connect(int, const struct sockaddr*, socklen_t);
-__socketcall int getpeername(int, struct sockaddr*, socklen_t*);
-__socketcall int getsockname(int, struct sockaddr*, socklen_t*);
-__socketcall int getsockopt(int, int, int, void*, socklen_t*);
-__socketcall int listen(int, int);
-__socketcall int recvmmsg(int, struct mmsghdr*, unsigned int, int, const struct timespec*)
+__socketcall int accept(int __fd, struct sockaddr* __addr, socklen_t* __addr_length);
+__socketcall int accept4(int __fd, struct sockaddr* __addr, socklen_t* __addr_length, int __flags) __INTRODUCED_IN(21);
+__socketcall int bind(int __fd, const struct sockaddr* __addr, socklen_t __addr_length);
+__socketcall int connect(int __fd, const struct sockaddr* __addr, socklen_t __addr_length);
+__socketcall int getpeername(int __fd, struct sockaddr* __addr, socklen_t* __addr_length);
+__socketcall int getsockname(int __fd, struct sockaddr* __addr, socklen_t* __addr_length);
+__socketcall int getsockopt(int __fd, int __level, int __option, void* __value, socklen_t* __value_length);
+__socketcall int listen(int __fd, int __backlog);
+__socketcall int recvmmsg(int __fd, struct mmsghdr* __msgs, unsigned int __msg_count, int __flags, const struct timespec* __timeout)
   __INTRODUCED_IN(21);
-__socketcall ssize_t recvmsg(int, struct msghdr*, int);
-__socketcall int sendmmsg(int, const struct mmsghdr*, unsigned int, int) __INTRODUCED_IN(21);
-__socketcall ssize_t sendmsg(int, const struct msghdr*, int);
-__socketcall int setsockopt(int, int, int, const void*, socklen_t);
-__socketcall int shutdown(int, int);
-__socketcall int socket(int, int, int);
-__socketcall int socketpair(int, int, int, int*);
+__socketcall ssize_t recvmsg(int __fd, struct msghdr* __msg, int __flags);
+__socketcall int sendmmsg(int __fd, const struct mmsghdr* __msgs, unsigned int __msg_count, int __flags) __INTRODUCED_IN(21);
+__socketcall ssize_t sendmsg(int __fd, const struct msghdr* __msg, int __flags);
+__socketcall int setsockopt(int __fd, int __level, int __option, const void* __value, socklen_t __value_length);
+__socketcall int shutdown(int __fd, int __how);
+__socketcall int socket(int __af, int __type, int __protocol);
+__socketcall int socketpair(int __af, int __type, int __protocol, int __fds[2]);
 
-ssize_t recv(int, void*, size_t, int) __overloadable __RENAME_CLANG(recv);
-ssize_t send(int, const void*, size_t, int) __overloadable __RENAME_CLANG(send);
+ssize_t recv(int __fd, void* __buf, size_t __n, int __flags) __overloadable __RENAME_CLANG(recv);
+ssize_t send(int __fd, const void* __buf, size_t __n, int __flags) __overloadable __RENAME_CLANG(send);
 
-__socketcall ssize_t sendto(int, const void*, size_t, int, const struct sockaddr*, socklen_t)
+__socketcall ssize_t sendto(int __fd, const void* __buf, size_t __n, int __flags, const struct sockaddr* __dst_addr, socklen_t __dst_addr_length)
         __overloadable __RENAME_CLANG(sendto);
-__socketcall ssize_t recvfrom(int, void*, size_t, int, struct sockaddr*,
-        socklen_t*) __overloadable __RENAME_CLANG(recvfrom);
+__socketcall ssize_t recvfrom(int __fd, void* __buf, size_t __n, int __flags, struct sockaddr* __src_addr, socklen_t* __src_addr_length) __overloadable __RENAME_CLANG(recvfrom);
 
 #if defined(__BIONIC_INCLUDE_FORTIFY_HEADERS)
 #include <bits/fortify/socket.h>
@@ -333,4 +332,4 @@
 
 __END_DECLS
 
-#endif /* _SYS_SOCKET_H */
+#endif
diff --git a/libc/include/sys/stat.h b/libc/include/sys/stat.h
index b8e3cb1..14b5224 100644
--- a/libc/include/sys/stat.h
+++ b/libc/include/sys/stat.h
@@ -151,46 +151,46 @@
 #define S_TYPEISSHM(__sb) 0
 #define S_TYPEISTMO(__sb) 0
 
-int chmod(const char*, mode_t);
-int fchmod(int, mode_t);
-int mkdir(const char*, mode_t);
+int chmod(const char* __path, mode_t __mode);
+int fchmod(int __fd, mode_t __mode);
+int mkdir(const char* __path, mode_t __mode);
 
-int fstat(int, struct stat*);
-int fstat64(int, struct stat64*) __INTRODUCED_IN(21);
-int fstatat(int, const char*, struct stat*, int);
-int fstatat64(int, const char*, struct stat64*, int) __INTRODUCED_IN(21);
-int lstat(const char*, struct stat*);
-int lstat64(const char*, struct stat64*) __INTRODUCED_IN(21);
-int stat(const char*, struct stat*);
-int stat64(const char*, struct stat64*) __INTRODUCED_IN(21);
+int fstat(int __fd, struct stat* __buf);
+int fstat64(int __fd, struct stat64* __buf) __INTRODUCED_IN(21);
+int fstatat(int __dir_fd, const char* __path, struct stat* __buf, int __flags);
+int fstatat64(int __dir_fd, const char* __path, struct stat64* __buf, int __flags) __INTRODUCED_IN(21);
+int lstat(const char* __path, struct stat* __buf);
+int lstat64(const char* __path, struct stat64* __buf) __INTRODUCED_IN(21);
+int stat(const char* __path, struct stat* __buf);
+int stat64(const char* __path, struct stat64* __buf) __INTRODUCED_IN(21);
 
-int mknod(const char*, mode_t, dev_t);
-mode_t umask(mode_t) __overloadable __RENAME_CLANG(umask);
+int mknod(const char* __path, mode_t __mode, dev_t __dev);
+mode_t umask(mode_t __mask) __overloadable __RENAME_CLANG(umask);
 
 #if defined(__BIONIC_INCLUDE_FORTIFY_HEADERS)
 #include <bits/fortify/stat.h>
 #endif
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
-int mkfifo(const char*, mode_t) __INTRODUCED_IN(21);
+int mkfifo(const char* __path, mode_t __mode) __INTRODUCED_IN(21);
 #else
 // Implemented as a static inline before 21.
 #endif
 
-int mkfifoat(int, const char*, mode_t) __INTRODUCED_IN(23);
+int mkfifoat(int __dir_fd, const char* __path, mode_t __mode) __INTRODUCED_IN(23);
 
-int fchmodat(int, const char*, mode_t, int);
-int mkdirat(int, const char*, mode_t);
-int mknodat(int, const char*, mode_t, dev_t) __INTRODUCED_IN(21);
+int fchmodat(int __dir_fd, const char* __path, mode_t __mode, int __flags);
+int mkdirat(int __dir_fd, const char* __path, mode_t __mode);
+int mknodat(int __dir_fd, const char* __path, mode_t __mode, dev_t __dev) __INTRODUCED_IN(21);
 
 #define UTIME_NOW  ((1L << 30) - 1L)
 #define UTIME_OMIT ((1L << 30) - 2L)
-int utimensat(int fd, const char* path, const struct timespec times[2], int flags)
+int utimensat(int __dir_fd, const char* __path, const struct timespec __times[2], int __flags)
   __INTRODUCED_IN(12);
-int futimens(int fd, const struct timespec times[2]) __INTRODUCED_IN(19);
+int futimens(int __dir_fd, const struct timespec __times[2]) __INTRODUCED_IN(19);
 
 __END_DECLS
 
 #include <android/legacy_sys_stat_inlines.h>
 
-#endif /* _SYS_STAT_H_ */
+#endif
diff --git a/libc/include/sys/statvfs.h b/libc/include/sys/statvfs.h
index 0f421a4..e60cadc 100644
--- a/libc/include/sys/statvfs.h
+++ b/libc/include/sys/statvfs.h
@@ -59,11 +59,11 @@
 #define ST_NODIRATIME  0x0800
 #define ST_RELATIME    0x1000
 
-int statvfs(const char*, struct statvfs*) __INTRODUCED_IN(19);
-int statvfs64(const char*, struct statvfs64*) __INTRODUCED_IN(21);
-int fstatvfs(int, struct statvfs*) __INTRODUCED_IN(19);
-int fstatvfs64(int, struct statvfs64*) __INTRODUCED_IN(21);
+int statvfs(const char* __path, struct statvfs* __buf) __INTRODUCED_IN(19);
+int statvfs64(const char* __path, struct statvfs64* __buf) __INTRODUCED_IN(21);
+int fstatvfs(int __fd, struct statvfs* __buf) __INTRODUCED_IN(19);
+int fstatvfs64(int __fd, struct statvfs64* __buf) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif /* _SYS_STATVFS_H_ */
+#endif
diff --git a/libc/include/sys/swap.h b/libc/include/sys/swap.h
index e79af97..8a30cce 100644
--- a/libc/include/sys/swap.h
+++ b/libc/include/sys/swap.h
@@ -38,9 +38,9 @@
 #define SWAP_FLAG_PRIO_MASK 0x7fff
 #define SWAP_FLAG_PRIO_SHIFT 0
 
-int swapon(const char*, int) __INTRODUCED_IN(19);
-int swapoff(const char*) __INTRODUCED_IN(19);
+int swapon(const char* __path,  int __flags) __INTRODUCED_IN(19);
+int swapoff(const char* __path) __INTRODUCED_IN(19);
 
 __END_DECLS
 
-#endif /* _SYS_SWAP_H_ */
+#endif
diff --git a/libc/include/sys/sysinfo.h b/libc/include/sys/sysinfo.h
index 9a10d64..6da02ee 100644
--- a/libc/include/sys/sysinfo.h
+++ b/libc/include/sys/sysinfo.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_SYSINFO_H_
 #define _SYS_SYSINFO_H_
 
@@ -33,16 +34,12 @@
 
 __BEGIN_DECLS
 
-int sysinfo(struct sysinfo* info);
-
+int sysinfo(struct sysinfo* __info);
 int get_nprocs_conf(void) __INTRODUCED_IN(23);
-
 int get_nprocs(void) __INTRODUCED_IN(23);
-
 long get_phys_pages(void) __INTRODUCED_IN(23);
-
 long get_avphys_pages(void) __INTRODUCED_IN(23);
 
 __END_DECLS
 
-#endif /* _SYS_SYSINFO_H_ */
+#endif
diff --git a/libc/include/sys/system_properties.h b/libc/include/sys/system_properties.h
index d075859..f469599 100644
--- a/libc/include/sys/system_properties.h
+++ b/libc/include/sys/system_properties.h
@@ -41,9 +41,9 @@
 #define PROP_VALUE_MAX  92
 
 /*
- * Sets system property `key` to `value`, creating the system property if it doesn't already exist.
+ * Sets system property `name` to `value`, creating the system property if it doesn't already exist.
  */
-int __system_property_set(const char* key, const char* value) __INTRODUCED_IN(12);
+int __system_property_set(const char* __name, const char* __value) __INTRODUCED_IN(12);
 
 /*
  * Returns a `prop_info` corresponding system property `name`, or nullptr if it doesn't exist.
@@ -51,14 +51,14 @@
  *
  * Property lookup is expensive, so it can be useful to cache the result of this function.
  */
-const prop_info* __system_property_find(const char* name);
+const prop_info* __system_property_find(const char* __name);
 
 /*
  * Calls `callback` with a consistent trio of name, value, and serial number for property `pi`.
  */
-void __system_property_read_callback(const prop_info *pi,
-    void (*callback)(void* cookie, const char *name, const char *value, uint32_t serial),
-    void* cookie) __INTRODUCED_IN(26);
+void __system_property_read_callback(const prop_info* __pi,
+    void (*__callback)(void* __cookie, const char* __name, const char* __value, uint32_t __serial),
+    void* __cookie) __INTRODUCED_IN(26);
 
 /*
  * Passes a `prop_info` for each system property to the provided
@@ -66,7 +66,7 @@
  *
  * This method is for inspecting and debugging the property system, and not generally useful.
  */
-int __system_property_foreach(void (*propfn)(const prop_info* pi, void* cookie), void* cookie)
+int __system_property_foreach(void (*__callback)(const prop_info* __pi, void* __cookie), void* __cookie)
   __INTRODUCED_IN(19);
 
 /*
@@ -82,20 +82,17 @@
  * timed out.
  */
 struct timespec;
-bool __system_property_wait(const prop_info* pi,
-                            uint32_t old_serial,
-                            uint32_t* new_serial_ptr,
-                            const struct timespec* relative_timeout)
+bool __system_property_wait(const prop_info* __pi, uint32_t __old_serial, uint32_t* __new_serial_ptr, const struct timespec* __relative_timeout)
     __INTRODUCED_IN(26);
 
 /* Deprecated. In Android O and above, there's no limit on property name length. */
 #define PROP_NAME_MAX   32
 /* Deprecated. Use __system_property_read_callback instead. */
-int __system_property_read(const prop_info* pi, char* name, char* value);
+int __system_property_read(const prop_info* __pi, char* __name, char* __value);
 /* Deprecated. Use __system_property_read_callback instead. */
-int __system_property_get(const char* name, char* value);
+int __system_property_get(const char* __name, char* __value);
 /* Deprecated. Use __system_property_foreach instead. */
-const prop_info* __system_property_find_nth(unsigned n);
+const prop_info* __system_property_find_nth(unsigned __n);
 
 __END_DECLS
 
diff --git a/libc/include/sys/time.h b/libc/include/sys/time.h
index 4d477e1..45190c3 100644
--- a/libc/include/sys/time.h
+++ b/libc/include/sys/time.h
@@ -38,21 +38,21 @@
 
 __BEGIN_DECLS
 
-int gettimeofday(struct timeval*, struct timezone*);
-int settimeofday(const struct timeval*, const struct timezone*);
+int gettimeofday(struct timeval* __tv, struct timezone* __tz);
+int settimeofday(const struct timeval* __tv, const struct timezone* __tz);
 
-int getitimer(int, struct itimerval*);
-int setitimer(int, const struct itimerval*, struct itimerval*);
+int getitimer(int __which, struct itimerval* __current_value);
+int setitimer(int __which, const struct itimerval* __new_value, struct itimerval* __old_value);
 
-int utimes(const char*, const struct timeval*);
+int utimes(const char* __path, const struct timeval __times[2]);
 
 #if defined(__USE_BSD)
-int futimes(int, const struct timeval[2]) __INTRODUCED_IN(26);
-int lutimes(const char*, const struct timeval[2]) __INTRODUCED_IN(26);
+int futimes(int __fd, const struct timeval __times[2]) __INTRODUCED_IN(26);
+int lutimes(const char* __path, const struct timeval __times[2]) __INTRODUCED_IN(26);
 #endif
 
 #if defined(__USE_GNU)
-int futimesat(int, const char*, const struct timeval[2]) __INTRODUCED_IN(26);
+int futimesat(int __dir_fd, const char* __path, const struct timeval __times[2]) __INTRODUCED_IN(26);
 #endif
 
 #define timerclear(a)   \
@@ -97,4 +97,4 @@
 
 __END_DECLS
 
-#endif /* _SYS_TIME_H_ */
+#endif
diff --git a/libc/include/sys/timerfd.h b/libc/include/sys/timerfd.h
index a500060..7bf675b 100644
--- a/libc/include/sys/timerfd.h
+++ b/libc/include/sys/timerfd.h
@@ -42,10 +42,10 @@
 #define TFD_CLOEXEC O_CLOEXEC
 #define TFD_NONBLOCK O_NONBLOCK
 
-int timerfd_create(clockid_t, int) __INTRODUCED_IN(19);
-int timerfd_settime(int, int, const struct itimerspec*, struct itimerspec*) __INTRODUCED_IN(19);
-int timerfd_gettime(int, struct itimerspec*) __INTRODUCED_IN(19);
+int timerfd_create(clockid_t __clock, int __flags) __INTRODUCED_IN(19);
+int timerfd_settime(int __fd, int __flags, const struct itimerspec* __new_value, struct itimerspec* __old_value) __INTRODUCED_IN(19);
+int timerfd_gettime(int __fd, struct itimerspec* __current_value) __INTRODUCED_IN(19);
 
 __END_DECLS
 
-#endif /* _SYS_TIMERFD_H */
+#endif
diff --git a/libc/include/sys/times.h b/libc/include/sys/times.h
index f52db1f..3c8a4ef 100644
--- a/libc/include/sys/times.h
+++ b/libc/include/sys/times.h
@@ -35,8 +35,8 @@
 
 __BEGIN_DECLS
 
-clock_t times(struct tms*);
+clock_t times(struct tms* __buf);
 
 __END_DECLS
 
-#endif /* _SYS_TIMES_H_ */
+#endif
diff --git a/libc/include/sys/timex.h b/libc/include/sys/timex.h
index f704ce8..74c8611 100644
--- a/libc/include/sys/timex.h
+++ b/libc/include/sys/timex.h
@@ -35,9 +35,9 @@
 
 __BEGIN_DECLS
 
-int adjtimex(struct timex*) __INTRODUCED_IN(24);
-int clock_adjtime(clockid_t, struct timex*) __INTRODUCED_IN(24);
+int adjtimex(struct timex* __buf) __INTRODUCED_IN(24);
+int clock_adjtime(clockid_t __clock, struct timex* __tx) __INTRODUCED_IN(24);
 
 __END_DECLS
 
-#endif /* _SYS_TIMEX_H_ */
+#endif
diff --git a/libc/include/sys/uio.h b/libc/include/sys/uio.h
index b166277..37961e3 100644
--- a/libc/include/sys/uio.h
+++ b/libc/include/sys/uio.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_UIO_H_
 #define _SYS_UIO_H_
 
@@ -34,23 +35,21 @@
 
 __BEGIN_DECLS
 
-ssize_t readv(int, const struct iovec*, int);
-ssize_t writev(int, const struct iovec*, int);
+ssize_t readv(int __fd, const struct iovec* __iov, int __count);
+ssize_t writev(int __fd, const struct iovec* __iov, int __count);
 
 #if defined(__USE_GNU)
-ssize_t preadv(int, const struct iovec*, int, off_t) __RENAME_IF_FILE_OFFSET64(preadv64) __INTRODUCED_IN(24);
-ssize_t pwritev(int, const struct iovec*, int, off_t) __RENAME_IF_FILE_OFFSET64(pwritev64) __INTRODUCED_IN(24);
-ssize_t preadv64(int, const struct iovec*, int, off64_t) __INTRODUCED_IN(24);
-ssize_t pwritev64(int, const struct iovec*, int, off64_t) __INTRODUCED_IN(24);
+ssize_t preadv(int __fd, const struct iovec* __iov, int __count, off_t __offset) __RENAME_IF_FILE_OFFSET64(preadv64) __INTRODUCED_IN(24);
+ssize_t pwritev(int __fd, const struct iovec* __iov, int __count, off_t __offset) __RENAME_IF_FILE_OFFSET64(pwritev64) __INTRODUCED_IN(24);
+ssize_t preadv64(int __fd, const struct iovec* __iov, int __count, off64_t __offset) __INTRODUCED_IN(24);
+ssize_t pwritev64(int __fd, const struct iovec* __iov, int __count, off64_t __offset) __INTRODUCED_IN(24);
 #endif
 
 #if defined(__USE_GNU)
-ssize_t process_vm_readv(pid_t, const struct iovec*, unsigned long, const struct iovec*,
-                         unsigned long, unsigned long) __INTRODUCED_IN(23);
-ssize_t process_vm_writev(pid_t, const struct iovec*, unsigned long, const struct iovec*,
-                          unsigned long, unsigned long) __INTRODUCED_IN(23);
+ssize_t process_vm_readv(pid_t __pid, const struct iovec* __local_iov, unsigned long __local_iov_count, const struct iovec* __remote_iov, unsigned long __remote_iov_count, unsigned long __flags) __INTRODUCED_IN(23);
+ssize_t process_vm_writev(pid_t __pid, const struct iovec* __local_iov, unsigned long __local_iov_count, const struct iovec* __remote_iov, unsigned long __remote_iov_count, unsigned long __flags) __INTRODUCED_IN(23);
 #endif
 
 __END_DECLS
 
-#endif /* _SYS_UIO_H_ */
+#endif
diff --git a/libc/include/sys/utsname.h b/libc/include/sys/utsname.h
index b3856a7..2420fb4 100644
--- a/libc/include/sys/utsname.h
+++ b/libc/include/sys/utsname.h
@@ -36,16 +36,16 @@
 #define SYS_NMLN 65
 
 struct utsname {
-    char  sysname   [SYS_NMLN];
-    char  nodename  [SYS_NMLN];
-    char  release   [SYS_NMLN];
-    char  version   [SYS_NMLN];
-    char  machine   [SYS_NMLN];
-    char  domainname[SYS_NMLN];
+  char sysname[SYS_NMLN];
+  char nodename[SYS_NMLN];
+  char release[SYS_NMLN];
+  char version[SYS_NMLN];
+  char machine[SYS_NMLN];
+  char domainname[SYS_NMLN];
 };
 
-int uname(struct utsname*);
+int uname(struct utsname* __buf);
 
 __END_DECLS
 
-#endif /* _SYS_UTSNAME_H_ */
+#endif
diff --git a/libc/include/sys/vfs.h b/libc/include/sys/vfs.h
index 3078683..9237ee6 100644
--- a/libc/include/sys/vfs.h
+++ b/libc/include/sys/vfs.h
@@ -137,11 +137,11 @@
 #define XENIX_SUPER_MAGIC     0x012FF7B4
 #define XFS_SUPER_MAGIC       0x58465342
 
-int statfs(const char*, struct statfs*);
-int statfs64(const char*, struct statfs64*) __INTRODUCED_IN(21);
-int fstatfs(int, struct statfs*);
-int fstatfs64(int, struct statfs64*) __INTRODUCED_IN(21);
+int statfs(const char* __path, struct statfs* __buf);
+int statfs64(const char* __path, struct statfs64* __buf) __INTRODUCED_IN(21);
+int fstatfs(int __fd, struct statfs* __buf);
+int fstatfs64(int __fd, struct statfs64* __buf) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif /* _SYS_VFS_H_ */
+#endif
diff --git a/libc/include/sys/wait.h b/libc/include/sys/wait.h
index 0247b2b..e259e31 100644
--- a/libc/include/sys/wait.h
+++ b/libc/include/sys/wait.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_WAIT_H_
 #define _SYS_WAIT_H_
 
@@ -49,10 +50,10 @@
 #define W_EXITCODE(ret, sig)    ((ret) << 8 | (sig))
 #define W_STOPCODE(sig)         ((sig) << 8 | 0x7f)
 
-pid_t wait(int*);
-pid_t waitpid(pid_t, int*, int);
+pid_t wait(int* __status);
+pid_t waitpid(pid_t __pid, int* __status, int __options);
 #if __ANDROID_API__ >= __ANDROID_API_J_MR2__
-pid_t wait4(pid_t, int*, int, struct rusage*) __INTRODUCED_IN(18);
+pid_t wait4(pid_t __pid, int* __status, int __options, struct rusage* __rusage) __INTRODUCED_IN(18);
 #else
 // Implemented as a static inline before 18.
 #endif
@@ -63,10 +64,10 @@
  */
 typedef int idtype_t;
 
-int waitid(idtype_t which, id_t id, siginfo_t* info, int options);
+int waitid(idtype_t __type, id_t __id, siginfo_t* __info, int __options);
 
 __END_DECLS
 
 #include <android/legacy_sys_wait_inlines.h>
 
-#endif /* _SYS_WAIT_H_ */
+#endif
diff --git a/libc/include/sys/xattr.h b/libc/include/sys/xattr.h
index 37e352d..d15b3fc 100644
--- a/libc/include/sys/xattr.h
+++ b/libc/include/sys/xattr.h
@@ -35,25 +35,25 @@
 
 __BEGIN_DECLS
 
-int fsetxattr(int fd, const char* name, const void* value, size_t size, int flags)
+int fsetxattr(int __fd, const char* __name, const void* __value, size_t __size, int __flags)
   __INTRODUCED_IN(16);
-int setxattr(const char* path, const char* name, const void* value, size_t size, int flags)
+int setxattr(const char* __path, const char* __name, const void* __value, size_t __size, int __flags)
   __INTRODUCED_IN(16);
-int lsetxattr(const char* path, const char* name, const void* value, size_t size, int flags)
+int lsetxattr(const char* __path, const char* __name, const void* __value, size_t __size, int __flags)
   __INTRODUCED_IN(16);
 
-ssize_t fgetxattr(int fd, const char* name, void* value, size_t size) __INTRODUCED_IN(16);
-ssize_t getxattr(const char* path, const char* name, void* value, size_t size) __INTRODUCED_IN(16);
-ssize_t lgetxattr(const char* path, const char* name, void* value, size_t size) __INTRODUCED_IN(16);
+ssize_t fgetxattr(int __fd, const char* __name, void* __value, size_t __size) __INTRODUCED_IN(16);
+ssize_t getxattr(const char* __path, const char* __name, void* __value, size_t __size) __INTRODUCED_IN(16);
+ssize_t lgetxattr(const char* __path, const char* __name, void* __value, size_t __size) __INTRODUCED_IN(16);
 
-ssize_t listxattr(const char* path, char* list, size_t size) __INTRODUCED_IN(16);
-ssize_t llistxattr(const char* path, char* list, size_t size) __INTRODUCED_IN(16);
-ssize_t flistxattr(int fd, char* list, size_t size) __INTRODUCED_IN(16);
+ssize_t listxattr(const char* __path, char* __list, size_t __size) __INTRODUCED_IN(16);
+ssize_t llistxattr(const char* __path, char* __list, size_t __size) __INTRODUCED_IN(16);
+ssize_t flistxattr(int __fd, char* __list, size_t __size) __INTRODUCED_IN(16);
 
-int removexattr(const char* path, const char* name) __INTRODUCED_IN(16);
-int lremovexattr(const char* path, const char* name) __INTRODUCED_IN(16);
-int fremovexattr(int fd, const char* name) __INTRODUCED_IN(16);
+int removexattr(const char* __path, const char* __name) __INTRODUCED_IN(16);
+int lremovexattr(const char* __path, const char* __name) __INTRODUCED_IN(16);
+int fremovexattr(int __fd, const char* __name) __INTRODUCED_IN(16);
 
 __END_DECLS
 
-#endif /* _SYS_XATTR_H_ */
+#endif
diff --git a/libc/include/syslog.h b/libc/include/syslog.h
index a320352..fff565e 100644
--- a/libc/include/syslog.h
+++ b/libc/include/syslog.h
@@ -87,10 +87,10 @@
 #define LOG_PERROR 0x20
 
 void closelog(void);
-void openlog(const char*, int, int);
-int setlogmask(int);
-void syslog(int, const char*, ...) __printflike(2, 3);
-void vsyslog(int, const char*, va_list) __printflike(2, 0);
+void openlog(const char* __prefix, int __option, int __facility);
+int setlogmask(int __mask);
+void syslog(int __priority, const char* __fmt, ...) __printflike(2, 3);
+void vsyslog(int __priority, const char* __fmt, va_list __args) __printflike(2, 0);
 
 __END_DECLS
 
diff --git a/libc/include/termios.h b/libc/include/termios.h
index 66ae71c..3eaab00 100644
--- a/libc/include/termios.h
+++ b/libc/include/termios.h
@@ -37,23 +37,23 @@
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
 // Implemented as static inlines before 21.
-speed_t cfgetispeed(const struct termios*) __INTRODUCED_IN(21);
-speed_t cfgetospeed(const struct termios*) __INTRODUCED_IN(21);
-void cfmakeraw(struct termios*) __INTRODUCED_IN(21);
-int cfsetspeed(struct termios*, speed_t) __INTRODUCED_IN(21);
-int cfsetispeed(struct termios*, speed_t) __INTRODUCED_IN(21);
-int cfsetospeed(struct termios*, speed_t) __INTRODUCED_IN(21);
-int tcdrain(int) __INTRODUCED_IN(21);
-int tcflow(int, int) __INTRODUCED_IN(21);
-int tcflush(int, int) __INTRODUCED_IN(21);
-int tcgetattr(int, struct termios*) __INTRODUCED_IN(21);
-pid_t tcgetsid(int) __INTRODUCED_IN(21);
-int tcsendbreak(int, int) __INTRODUCED_IN(21);
-int tcsetattr(int, int, const struct termios*) __INTRODUCED_IN(21);
+speed_t cfgetispeed(const struct termios* __t) __INTRODUCED_IN(21);
+speed_t cfgetospeed(const struct termios* __t) __INTRODUCED_IN(21);
+void cfmakeraw(struct termios* __t) __INTRODUCED_IN(21);
+int cfsetspeed(struct termios* __t, speed_t __speed) __INTRODUCED_IN(21);
+int cfsetispeed(struct termios* __t, speed_t __speed) __INTRODUCED_IN(21);
+int cfsetospeed(struct termios* __t, speed_t __speed) __INTRODUCED_IN(21);
+int tcdrain(int __fd) __INTRODUCED_IN(21);
+int tcflow(int __fd, int __action) __INTRODUCED_IN(21);
+int tcflush(int __fd, int __queue) __INTRODUCED_IN(21);
+int tcgetattr(int __fd, struct termios* __t) __INTRODUCED_IN(21);
+pid_t tcgetsid(int __fd) __INTRODUCED_IN(21);
+int tcsendbreak(int __fd, int __duration) __INTRODUCED_IN(21);
+int tcsetattr(int __fd, int __optional_actions, const struct termios* __t) __INTRODUCED_IN(21);
 #endif
 
 __END_DECLS
 
 #include <android/legacy_termios_inlines.h>
 
-#endif /* _TERMIOS_H_ */
+#endif
diff --git a/libc/include/time.h b/libc/include/time.h
index 9fde77e..8e78949 100644
--- a/libc/include/time.h
+++ b/libc/include/time.h
@@ -59,54 +59,54 @@
 
 #define TM_ZONE tm_zone
 
-time_t time(time_t*);
-int nanosleep(const struct timespec*, struct timespec*);
+time_t time(time_t* __t);
+int nanosleep(const struct timespec* __request, struct timespec* __remainder);
 
-char* asctime(const struct tm*);
-char* asctime_r(const struct tm*, char*);
+char* asctime(const struct tm* __tm);
+char* asctime_r(const struct tm* __tm, char* __buf);
 
-double difftime(time_t, time_t);
-time_t mktime(struct tm*);
+double difftime(time_t __lhs, time_t __rhs);
+time_t mktime(struct tm* __tm);
 
-struct tm* localtime(const time_t*);
-struct tm* localtime_r(const time_t*, struct tm*);
+struct tm* localtime(const time_t* __t);
+struct tm* localtime_r(const time_t* __t, struct tm* __tm);
 
-struct tm* gmtime(const time_t*);
-struct tm* gmtime_r(const time_t*, struct tm*);
+struct tm* gmtime(const time_t* __t);
+struct tm* gmtime_r(const time_t* __t, struct tm* __tm);
 
-char* strptime(const char*, const char*, struct tm*);
-size_t strftime(char*, size_t, const char*, const struct tm*);
+char* strptime(const char* __s, const char* __fmt, struct tm* __tm);
+size_t strftime(char* __buf, size_t __n, const char* __fmt, const struct tm* __tm);
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
-size_t strftime_l(char*, size_t, const char*, const struct tm*, locale_t) __INTRODUCED_IN(21);
+size_t strftime_l(char* __buf, size_t __n, const char* __fmt, const struct tm* __tm, locale_t __l) __INTRODUCED_IN(21);
 #else
 // Implemented as static inline before 21.
 #endif
 
-char* ctime(const time_t*);
-char* ctime_r(const time_t*, char*);
+char* ctime(const time_t* __t);
+char* ctime_r(const time_t* __t, char* __buf);
 
 void tzset(void);
 
 clock_t clock(void);
 
-int clock_getcpuclockid(pid_t, clockid_t*) __INTRODUCED_IN(23);
+int clock_getcpuclockid(pid_t __pid, clockid_t* __clock) __INTRODUCED_IN(23);
 
-int clock_getres(clockid_t, struct timespec*);
-int clock_gettime(clockid_t, struct timespec*);
-int clock_nanosleep(clockid_t, int, const struct timespec*, struct timespec*);
-int clock_settime(clockid_t, const struct timespec*);
+int clock_getres(clockid_t __clock, struct timespec* __resolution);
+int clock_gettime(clockid_t __clock, struct timespec* __ts);
+int clock_nanosleep(clockid_t __clock, int __flags, const struct timespec* __request, struct timespec* __remainder);
+int clock_settime(clockid_t __clock, const struct timespec* __ts);
 
-int timer_create(int, struct sigevent*, timer_t*);
-int timer_delete(timer_t);
-int timer_settime(timer_t, int, const struct itimerspec*, struct itimerspec*);
-int timer_gettime(timer_t, struct itimerspec*);
-int timer_getoverrun(timer_t);
+int timer_create(clockid_t __clock, struct sigevent* __event, timer_t* __timer_ptr);
+int timer_delete(timer_t __timer);
+int timer_settime(timer_t __timer, int __flags, const struct itimerspec* __new_value, struct itimerspec* __old_value);
+int timer_gettime(timer_t __timer, struct itimerspec* __ts);
+int timer_getoverrun(timer_t __timer);
 
 /* Non-standard extensions that are in the BSDs and glibc. */
-time_t timelocal(struct tm*) __INTRODUCED_IN(12);
-time_t timegm(struct tm*) __INTRODUCED_IN(12);
+time_t timelocal(struct tm* __tm) __INTRODUCED_IN(12);
+time_t timegm(struct tm* __tm) __INTRODUCED_IN(12);
 
 __END_DECLS
 
-#endif /* _TIME_H_ */
+#endif
diff --git a/libc/include/uchar.h b/libc/include/uchar.h
index ac0cf1d..e59d6a9 100644
--- a/libc/include/uchar.h
+++ b/libc/include/uchar.h
@@ -43,11 +43,11 @@
 #define __STD_UTF_16__ 1
 #define __STD_UTF_32__ 1
 
-size_t c16rtomb(char*, char16_t, mbstate_t*) __INTRODUCED_IN(21);
-size_t c32rtomb(char*, char32_t, mbstate_t*) __INTRODUCED_IN(21);
-size_t mbrtoc16(char16_t*, const char*, size_t, mbstate_t*) __INTRODUCED_IN(21);
-size_t mbrtoc32(char32_t*, const char*, size_t, mbstate_t*) __INTRODUCED_IN(21);
+size_t c16rtomb(char* __buf, char16_t __ch16, mbstate_t* __ps) __INTRODUCED_IN(21);
+size_t c32rtomb(char* __buf, char32_t __ch32, mbstate_t* __ps) __INTRODUCED_IN(21);
+size_t mbrtoc16(char16_t* __ch16, const char* __s, size_t __n, mbstate_t* __ps) __INTRODUCED_IN(21);
+size_t mbrtoc32(char32_t* __ch32, const char* __s, size_t __n, mbstate_t* __ps) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif /* _UCHAR_H_ */
+#endif
diff --git a/libc/include/utime.h b/libc/include/utime.h
index 9783859..be6b894 100644
--- a/libc/include/utime.h
+++ b/libc/include/utime.h
@@ -35,8 +35,8 @@
 
 __BEGIN_DECLS
 
-int utime(const char*, const struct utimbuf*);
+int utime(const char* __filename, const struct utimbuf* __times);
 
 __END_DECLS
 
-#endif /* _UTIME_H_ */
+#endif
diff --git a/libc/include/utmp.h b/libc/include/utmp.h
index 62e8d59..6a52511 100644
--- a/libc/include/utmp.h
+++ b/libc/include/utmp.h
@@ -96,12 +96,12 @@
 
 __BEGIN_DECLS
 
-int utmpname(const char*);
+int utmpname(const char* __path);
 void setutent(void);
 struct utmp* getutent(void);
 void endutent(void);
 
-int login_tty(int) __INTRODUCED_IN(23);
+int login_tty(int __fd) __INTRODUCED_IN(23);
 
 __END_DECLS
 
diff --git a/libc/include/wchar.h b/libc/include/wchar.h
index 4494cb0..1dda4bd 100644
--- a/libc/include/wchar.h
+++ b/libc/include/wchar.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _WCHAR_H_
 #define _WCHAR_H_
 
@@ -42,98 +43,98 @@
 
 __BEGIN_DECLS
 
-wint_t            btowc(int);
-int               fwprintf(FILE *, const wchar_t *, ...);
-int               fwscanf(FILE *, const wchar_t *, ...);
-wint_t            fgetwc(FILE *);
-wchar_t          *fgetws(wchar_t *, int, FILE *);
-wint_t            fputwc(wchar_t, FILE *);
-int               fputws(const wchar_t *, FILE *);
-int               fwide(FILE *, int);
-wint_t            getwc(FILE *);
-wint_t            getwchar(void);
-int               mbsinit(const mbstate_t *);
-size_t            mbrlen(const char *, size_t, mbstate_t *);
-size_t            mbrtowc(wchar_t *, const char *, size_t, mbstate_t *);
-size_t mbsrtowcs(wchar_t*, const char**, size_t, mbstate_t*);
-size_t mbsnrtowcs(wchar_t*, const char**, size_t, size_t, mbstate_t*) __INTRODUCED_IN(21);
-wint_t            putwc(wchar_t, FILE *);
-wint_t            putwchar(wchar_t);
-int               swprintf(wchar_t *, size_t, const wchar_t *, ...);
-int               swscanf(const wchar_t *, const wchar_t *, ...);
-wint_t            ungetwc(wint_t, FILE *);
-int vfwprintf(FILE*, const wchar_t*, va_list);
-int vfwscanf(FILE*, const wchar_t*, va_list) __INTRODUCED_IN(21);
-int vswprintf(wchar_t*, size_t, const wchar_t*, va_list);
-int vswscanf(const wchar_t*, const wchar_t*, va_list) __INTRODUCED_IN(21);
-int vwprintf(const wchar_t*, va_list);
-int vwscanf(const wchar_t*, va_list) __INTRODUCED_IN(21);
-wchar_t* wcpcpy (wchar_t*, const wchar_t *);
-wchar_t* wcpncpy (wchar_t*, const wchar_t *, size_t);
-size_t            wcrtomb(char *, wchar_t, mbstate_t *);
-int               wcscasecmp(const wchar_t *, const wchar_t *);
-int wcscasecmp_l(const wchar_t*, const wchar_t*, locale_t) __INTRODUCED_IN(23);
-wchar_t          *wcscat(wchar_t *, const wchar_t *);
-wchar_t          *wcschr(const wchar_t *, wchar_t);
-int               wcscmp(const wchar_t *, const wchar_t *);
-int               wcscoll(const wchar_t *, const wchar_t *);
-wchar_t          *wcscpy(wchar_t *, const wchar_t *);
-size_t            wcscspn(const wchar_t *, const wchar_t *);
-size_t            wcsftime(wchar_t *, size_t, const wchar_t *, const struct tm *);
-size_t            wcslen(const wchar_t *);
-int               wcsncasecmp(const wchar_t *, const wchar_t *, size_t);
-int wcsncasecmp_l(const wchar_t*, const wchar_t*, size_t, locale_t) __INTRODUCED_IN(23);
-wchar_t          *wcsncat(wchar_t *, const wchar_t *, size_t);
-int               wcsncmp(const wchar_t *, const wchar_t *, size_t);
-wchar_t          *wcsncpy(wchar_t *, const wchar_t *, size_t);
-size_t wcsnrtombs(char*, const wchar_t**, size_t, size_t, mbstate_t*) __INTRODUCED_IN(21);
-wchar_t          *wcspbrk(const wchar_t *, const wchar_t *);
-wchar_t          *wcsrchr(const wchar_t *, wchar_t);
-size_t wcsrtombs(char*, const wchar_t**, size_t, mbstate_t*);
-size_t            wcsspn(const wchar_t *, const wchar_t *);
-wchar_t          *wcsstr(const wchar_t *, const wchar_t *);
-double wcstod(const wchar_t*, wchar_t**);
-float wcstof(const wchar_t*, wchar_t**) __INTRODUCED_IN(21);
-wchar_t* wcstok(wchar_t*, const wchar_t*, wchar_t**);
-long wcstol(const wchar_t*, wchar_t**, int);
-long long wcstoll(const wchar_t*, wchar_t**, int) __INTRODUCED_IN(21);
-long double wcstold(const wchar_t*, wchar_t**) __INTRODUCED_IN(21);
-unsigned long wcstoul(const wchar_t*, wchar_t**, int);
-unsigned long long wcstoull(const wchar_t*, wchar_t**, int) __INTRODUCED_IN(21);
-int               wcswidth(const wchar_t *, size_t);
-size_t            wcsxfrm(wchar_t *, const wchar_t *, size_t);
-int               wctob(wint_t);
-int               wcwidth(wchar_t);
-wchar_t          *wmemchr(const wchar_t *, wchar_t, size_t);
-int               wmemcmp(const wchar_t *, const wchar_t *, size_t);
-wchar_t          *wmemcpy(wchar_t *, const wchar_t *, size_t);
+wint_t btowc(int __ch);
+int fwprintf(FILE* __fp, const wchar_t* __fmt, ...);
+int fwscanf(FILE* __fp, const wchar_t* __fmt, ...);
+wint_t fgetwc(FILE* __fp);
+wchar_t* fgetws(wchar_t* __buf, int __size, FILE* __fp);
+wint_t fputwc(wchar_t __wc, FILE* __fp);
+int fputws(const wchar_t* __s, FILE* __fp);
+int fwide(FILE* __fp, int __mode);
+wint_t getwc(FILE* __fp);
+wint_t getwchar(void);
+int mbsinit(const mbstate_t* __ps);
+size_t mbrlen(const char* __s, size_t __n, mbstate_t* __ps);
+size_t mbrtowc(wchar_t* __buf, const char* __s, size_t __n, mbstate_t* __ps);
+size_t mbsrtowcs(wchar_t* __dst, const char** __src, size_t __dst_n, mbstate_t* __ps);
+size_t mbsnrtowcs(wchar_t* __dst, const char** __src, size_t __src_n, size_t __dst_n, mbstate_t* __ps) __INTRODUCED_IN(21);
+wint_t putwc(wchar_t __wc, FILE* __fp);
+wint_t putwchar(wchar_t __wc);
+int swprintf(wchar_t* __buf, size_t __n, const wchar_t* __fmt, ...);
+int swscanf(const wchar_t* __s, const wchar_t* __fmt, ...);
+wint_t ungetwc(wint_t __wc, FILE* __fp);
+int vfwprintf(FILE* __fp, const wchar_t* __fmt, va_list __args);
+int vfwscanf(FILE* __fp, const wchar_t* __fmt, va_list __args) __INTRODUCED_IN(21);
+int vswprintf(wchar_t* __buf, size_t __n, const wchar_t* __fmt, va_list __args);
+int vswscanf(const wchar_t* __s, const wchar_t* __fmt, va_list __args) __INTRODUCED_IN(21);
+int vwprintf(const wchar_t* __fmt, va_list __args);
+int vwscanf(const wchar_t* __fmt, va_list __args) __INTRODUCED_IN(21);
+wchar_t* wcpcpy(wchar_t* __dst, const wchar_t* __src);
+wchar_t* wcpncpy(wchar_t* __dst, const wchar_t* __src, size_t __n);
+size_t wcrtomb(char* __buf, wchar_t __wc, mbstate_t* __ps);
+int wcscasecmp(const wchar_t* __lhs, const wchar_t* __rhs);
+int wcscasecmp_l(const wchar_t* __lhs, const wchar_t* __rhs, locale_t __l) __INTRODUCED_IN(23);
+wchar_t* wcscat(wchar_t* __dst, const wchar_t* __src);
+wchar_t* wcschr(const wchar_t* __s, wchar_t __wc);
+int wcscmp(const wchar_t* __lhs, const wchar_t* __rhs);
+int wcscoll(const wchar_t* __lhs, const wchar_t* __rhs);
+wchar_t* wcscpy(wchar_t* __dst, const wchar_t* __src);
+size_t wcscspn(const wchar_t* __s, const wchar_t* __accept);
+size_t wcsftime(wchar_t* __buf, size_t __n, const wchar_t* __fmt, const struct tm* __tm);
+size_t wcslen(const wchar_t* __s);
+int wcsncasecmp(const wchar_t* __lhs, const wchar_t* __rhs, size_t __n);
+int wcsncasecmp_l(const wchar_t* __lhs, const wchar_t* __rhs, size_t __n, locale_t __l) __INTRODUCED_IN(23);
+wchar_t* wcsncat(wchar_t* __dst, const wchar_t* __src, size_t __n);
+int wcsncmp(const wchar_t* __lhs, const wchar_t* __rhs, size_t __n);
+wchar_t* wcsncpy(wchar_t* __dst, const wchar_t* __src, size_t __n);
+size_t wcsnrtombs(char* __dst, const wchar_t** __src, size_t __src_n, size_t __dst_n, mbstate_t* __ps) __INTRODUCED_IN(21);
+wchar_t* wcspbrk(const wchar_t* __s, const wchar_t* __accept);
+wchar_t* wcsrchr(const wchar_t* __s, wchar_t __wc);
+size_t wcsrtombs(char* __dst, const wchar_t** __src, size_t __dst_n, mbstate_t* __ps);
+size_t wcsspn(const wchar_t* __s, const wchar_t* __accept);
+wchar_t* wcsstr(const wchar_t* __haystack, const wchar_t* __needle);
+double wcstod(const wchar_t* __s, wchar_t** __end_ptr);
+float wcstof(const wchar_t* __s, wchar_t** __end_ptr) __INTRODUCED_IN(21);
+wchar_t* wcstok(wchar_t* __s, const wchar_t* __delimiter, wchar_t** __ptr);
+long wcstol(const wchar_t* __s, wchar_t** __end_ptr, int __base);
+long long wcstoll(const wchar_t* __s, wchar_t** __end_ptr, int __base) __INTRODUCED_IN(21);
+long double wcstold(const wchar_t* __s, wchar_t** __end_ptr) __INTRODUCED_IN(21);
+unsigned long wcstoul(const wchar_t* __s, wchar_t** __end_ptr, int __base);
+unsigned long long wcstoull(const wchar_t* __s, wchar_t** __end_ptr, int __base) __INTRODUCED_IN(21);
+int wcswidth(const wchar_t* __s, size_t __n);
+size_t wcsxfrm(wchar_t* __dst, const wchar_t* __src, size_t __n);
+int wctob(wint_t __wc);
+int wcwidth(wchar_t __wc);
+wchar_t* wmemchr(const wchar_t* __src, wchar_t __wc, size_t __n);
+int wmemcmp(const wchar_t* __lhs, const wchar_t* __rhs, size_t __n);
+wchar_t* wmemcpy(wchar_t* __dst, const wchar_t* __src, size_t __n);
 #if defined(__USE_GNU)
-wchar_t* wmempcpy(wchar_t*, const wchar_t*, size_t) __INTRODUCED_IN(23);
+wchar_t* wmempcpy(wchar_t* __dst, const wchar_t* __src, size_t __n) __INTRODUCED_IN(23);
 #endif
-wchar_t          *wmemmove(wchar_t *, const wchar_t *, size_t);
-wchar_t          *wmemset(wchar_t *, wchar_t, size_t);
-int               wprintf(const wchar_t *, ...);
-int               wscanf(const wchar_t *, ...);
+wchar_t* wmemmove(wchar_t* __dst, const wchar_t* __src, size_t __n);
+wchar_t* wmemset(wchar_t* __dst, wchar_t __wc, size_t __n);
+int wprintf(const wchar_t* __fmt, ...);
+int wscanf(const wchar_t* __fmt, ...);
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
-long long wcstoll_l(const wchar_t*, wchar_t**, int, locale_t) __INTRODUCED_IN(21);
-unsigned long long wcstoull_l(const wchar_t*, wchar_t**, int, locale_t) __INTRODUCED_IN(21);
-long double wcstold_l(const wchar_t*, wchar_t**, locale_t) __INTRODUCED_IN(21);
+long long wcstoll_l(const wchar_t* __s, wchar_t** __end_ptr, int __base, locale_t __l) __INTRODUCED_IN(21);
+unsigned long long wcstoull_l(const wchar_t* __s, wchar_t** __end_ptr, int __base, locale_t __l) __INTRODUCED_IN(21);
+long double wcstold_l(const wchar_t* __s, wchar_t** __end_ptr, locale_t __l) __INTRODUCED_IN(21);
 
-int wcscoll_l(const wchar_t*, const wchar_t*, locale_t) __attribute_pure__
+int wcscoll_l(const wchar_t* __lhs, const wchar_t* __rhs, locale_t __l) __attribute_pure__
     __INTRODUCED_IN(21);
-size_t wcsxfrm_l(wchar_t*, const wchar_t*, size_t, locale_t) __INTRODUCED_IN(21);
+size_t wcsxfrm_l(wchar_t* __dst, const wchar_t* __src, size_t __n, locale_t __l) __INTRODUCED_IN(21);
 #else
 // Implemented as static inlines before 21.
 #endif
 
-size_t wcslcat(wchar_t*, const wchar_t*, size_t);
-size_t wcslcpy(wchar_t*, const wchar_t*, size_t);
+size_t wcslcat(wchar_t* __dst, const wchar_t* __src, size_t __n);
+size_t wcslcpy(wchar_t* __dst, const wchar_t* __src, size_t __n);
 
-FILE* open_wmemstream(wchar_t**, size_t*) __INTRODUCED_IN(23);
-wchar_t* wcsdup(const wchar_t*);
-size_t wcsnlen(const wchar_t*, size_t);
+FILE* open_wmemstream(wchar_t** __ptr, size_t* __size_ptr) __INTRODUCED_IN(23);
+wchar_t* wcsdup(const wchar_t* __s);
+size_t wcsnlen(const wchar_t* __s, size_t __n);
 
 __END_DECLS
 
-#endif /* _WCHAR_H_ */
+#endif
diff --git a/libc/include/wctype.h b/libc/include/wctype.h
index 39e34f6..18f5c4b 100644
--- a/libc/include/wctype.h
+++ b/libc/include/wctype.h
@@ -36,31 +36,31 @@
 __BEGIN_DECLS
 
 #if __ANDROID_API__ >= __ANDROID_API_L__
-int iswalnum_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswalpha_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswblank_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswcntrl_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswdigit_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswgraph_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswlower_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswprint_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswpunct_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswspace_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswupper_l(wint_t, locale_t) __INTRODUCED_IN(21);
-int iswxdigit_l(wint_t, locale_t) __INTRODUCED_IN(21);
+int iswalnum_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswalpha_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswblank_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswcntrl_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswdigit_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswgraph_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswlower_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswprint_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswpunct_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswspace_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswupper_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+int iswxdigit_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
 
-wint_t towlower_l(wint_t, locale_t) __INTRODUCED_IN(21);
-wint_t towupper_l(wint_t, locale_t) __INTRODUCED_IN(21);
+wint_t towlower_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
+wint_t towupper_l(wint_t __wc, locale_t __l) __INTRODUCED_IN(21);
 #else
 // Implemented as static inlines before 21.
 #endif
 
-wint_t towctrans_l(wint_t, wctrans_t, locale_t) __INTRODUCED_IN(26);
-wctrans_t wctrans_l(const char*, locale_t) __INTRODUCED_IN(26);
+wint_t towctrans_l(wint_t __wc, wctrans_t __transform, locale_t __l) __INTRODUCED_IN(26);
+wctrans_t wctrans_l(const char* __name, locale_t __l) __INTRODUCED_IN(26);
 
-wctype_t wctype_l(const char*, locale_t) __INTRODUCED_IN(21);
-int iswctype_l(wint_t, wctype_t, locale_t) __INTRODUCED_IN(21);
+wctype_t wctype_l(const char* __name, locale_t __l) __INTRODUCED_IN(21);
+int iswctype_l(wint_t __wc, wctype_t __transform, locale_t __l) __INTRODUCED_IN(21);
 
 __END_DECLS
 
-#endif /* _WCTYPE_H_ */
+#endif
diff --git a/libc/malloc_debug/README.md b/libc/malloc_debug/README.md
index b77af6d..03a8a73 100644
--- a/libc/malloc_debug/README.md
+++ b/libc/malloc_debug/README.md
@@ -371,6 +371,9 @@
 
 Examples
 ========
+
+### For platform developers
+
 Enable backtrace tracking of all allocation for all processes:
 
     adb shell stop
@@ -427,17 +430,7 @@
 but, obviously, it must be enabled through the signal before the file will
 contain any data.
 
-To analyze the data produced by the dumpheap command, run this script:
-
-    development/scripts/native_heapdump_viewer.py
-
-In order for the script to properly symbolize the stacks in the file,
-make sure the script is executed from the tree that built the image.
-Below is an example of how to execute the script using the dump created by the
-above command:
-
-    adb shell pull /data/local/tmp/heap.txt .
-    development/scripts/native_heapdump_viewer.py heap.txt > heap_info.txt
+### For app developers
 
 Enable malloc debug for a specific program/application (Android O or later):
 
@@ -453,3 +446,40 @@
 was necessary to truncate the name to fit. On O, property names can be
 an order of magnitude larger, so there should be no need to truncate the name
 at all.
+
+To detect leaks while an app is running:
+
+    adb shell dumpsys meminfo --unreachable <PID_OF_APP>
+
+Without also enabling malloc debug, this command will only tell
+you whether it can detect leaked memory, not where those leaks are
+occurring. If you enable malloc debug with the backtrace option for your
+app before running the dumpsys command, you'll get backtraces showing
+where the memory was allocated.
+
+For backtraces from your app to be useful, you'll want to keep the
+symbols in your app's shared libraries rather than stripping them. That
+way you'll see the location of the leak directly without having to use
+something like the <code>ndk-stack</code> tool.
+
+### Analyzing heap dumps
+
+To analyze the data produced by the dumpheap command, run this script:
+
+    development/scripts/native_heapdump_viewer.py
+
+In order for the script to properly symbolize the stacks in the file,
+make sure the script is executed from the tree that built the image.
+
+To collect, transfer, and analyze a dump:
+
+    adb shell am dumpheap -n <PID_TO_DUMP> /data/local/tmp/heap.txt
+    adb shell pull /data/local/tmp/heap.txt .
+    python development/scripts/native_heapdump_viewer.py --symbols /some/path/to/symbols/ heap.txt > heap_info.txt
+
+At the moment, the script will look for symbols in the given directory,
+using the path the .so file would have on the device. So if your .so file
+is at `/data/app/.../lib/arm/libx.so` on the device, it will need to be at
+`/some/path/to/symbols/data/app/.../lib/arm/libx.so` locally given the
+command line above. That is: you need to mirror the directory structure
+for the app in the symbols directory.
diff --git a/libc/private/CFIShadow.h b/libc/private/CFIShadow.h
index 26351db..1423d86 100644
--- a/libc/private/CFIShadow.h
+++ b/libc/private/CFIShadow.h
@@ -61,10 +61,8 @@
   // Alignment of __cfi_check.
   static constexpr uintptr_t kCfiCheckAlign = 1UL << kCfiCheckGranularity;  // 4K
 
-#if defined(__aarch64__)
-  static constexpr uintptr_t kMaxTargetAddr = 0x7fffffffff;
-#elif defined (__LP64__)
-  static constexpr uintptr_t kMaxTargetAddr = 0x7fffffffffff;
+#if defined (__LP64__)
+  static constexpr uintptr_t kMaxTargetAddr = 0xffffffffffff;
 #else
   static constexpr uintptr_t kMaxTargetAddr = 0xffffffff;
 #endif
diff --git a/libdl/libdl.arm.map b/libdl/libdl.arm.map
index 292bd97..9fc9d23 100644
--- a/libdl/libdl.arm.map
+++ b/libdl/libdl.arm.map
@@ -36,6 +36,7 @@
 
 LIBC_OMR1 { # future
   global:
+    __cfi_shadow_size; # future
     __cfi_slowpath; # future
     __cfi_slowpath_diag; # future
 } LIBC_N;
diff --git a/libdl/libdl.arm64.map b/libdl/libdl.arm64.map
index 2fe2c7b..bde6cab 100644
--- a/libdl/libdl.arm64.map
+++ b/libdl/libdl.arm64.map
@@ -35,6 +35,7 @@
 
 LIBC_OMR1 { # future
   global:
+    __cfi_shadow_size; # future
     __cfi_slowpath; # future
     __cfi_slowpath_diag; # future
 } LIBC_N;
diff --git a/libdl/libdl.map.txt b/libdl/libdl.map.txt
index 408d4dc..d1f4ab8 100644
--- a/libdl/libdl.map.txt
+++ b/libdl/libdl.map.txt
@@ -35,6 +35,7 @@
 
 LIBC_OMR1 { # future
   global:
+    __cfi_shadow_size; # future
     __cfi_slowpath; # future
     __cfi_slowpath_diag; # future
 } LIBC_N;
diff --git a/libdl/libdl.mips.map b/libdl/libdl.mips.map
index 2fe2c7b..bde6cab 100644
--- a/libdl/libdl.mips.map
+++ b/libdl/libdl.mips.map
@@ -35,6 +35,7 @@
 
 LIBC_OMR1 { # future
   global:
+    __cfi_shadow_size; # future
     __cfi_slowpath; # future
     __cfi_slowpath_diag; # future
 } LIBC_N;
diff --git a/libdl/libdl.mips64.map b/libdl/libdl.mips64.map
index 2fe2c7b..bde6cab 100644
--- a/libdl/libdl.mips64.map
+++ b/libdl/libdl.mips64.map
@@ -35,6 +35,7 @@
 
 LIBC_OMR1 { # future
   global:
+    __cfi_shadow_size; # future
     __cfi_slowpath; # future
     __cfi_slowpath_diag; # future
 } LIBC_N;
diff --git a/libdl/libdl.x86.map b/libdl/libdl.x86.map
index 2fe2c7b..bde6cab 100644
--- a/libdl/libdl.x86.map
+++ b/libdl/libdl.x86.map
@@ -35,6 +35,7 @@
 
 LIBC_OMR1 { # future
   global:
+    __cfi_shadow_size; # future
     __cfi_slowpath; # future
     __cfi_slowpath_diag; # future
 } LIBC_N;
diff --git a/libdl/libdl.x86_64.map b/libdl/libdl.x86_64.map
index 2fe2c7b..bde6cab 100644
--- a/libdl/libdl.x86_64.map
+++ b/libdl/libdl.x86_64.map
@@ -35,6 +35,7 @@
 
 LIBC_OMR1 { # future
   global:
+    __cfi_shadow_size; # future
     __cfi_slowpath; # future
     __cfi_slowpath_diag; # future
 } LIBC_N;
diff --git a/libdl/libdl_cfi.cpp b/libdl/libdl_cfi.cpp
index 8458564..483364f 100644
--- a/libdl/libdl_cfi.cpp
+++ b/libdl/libdl_cfi.cpp
@@ -38,6 +38,11 @@
   return &shadow_base_storage.v;
 }
 
+// Returns the size of the CFI shadow mapping, or 0 if CFI is not (yet) used in this process.
+extern "C" size_t __cfi_shadow_size() {
+  return shadow_base_storage.v != 0 ? CFIShadow::kShadowSize : 0;
+}
+
 static uint16_t shadow_load(void* p) {
   uintptr_t addr = reinterpret_cast<uintptr_t>(p);
   uintptr_t ofs = CFIShadow::MemToShadowOffset(addr);
diff --git a/linker/linker.cpp b/linker/linker.cpp
index a212624..8aadd14 100644
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -3506,6 +3506,9 @@
   g_default_namespace.set_permitted_paths(default_ns_config->permitted_paths());
 
   namespaces[default_ns_config->name()] = &g_default_namespace;
+  if (default_ns_config->visible()) {
+    g_exported_namespaces[default_ns_config->name()] = &g_default_namespace;
+  }
 
   // 2. Initialize other namespaces
 
diff --git a/tests/cfi_test.cpp b/tests/cfi_test.cpp
index 5e627a7..088dda6 100644
--- a/tests/cfi_test.cpp
+++ b/tests/cfi_test.cpp
@@ -26,6 +26,7 @@
 extern "C" {
 void __cfi_slowpath(uint64_t CallSiteTypeId, void* Ptr);
 void __cfi_slowpath_diag(uint64_t CallSiteTypeId, void* Ptr, void* DiagData);
+size_t __cfi_shadow_size();
 }
 
 static void f() {}
@@ -36,6 +37,8 @@
   handle = dlopen("libcfi-test.so", RTLD_NOW | RTLD_LOCAL);
   ASSERT_TRUE(handle != nullptr) << dlerror();
 
+  EXPECT_NE(0U, __cfi_shadow_size());
+
 #define SYM(type, name) auto name = reinterpret_cast<type>(dlsym(handle, #name))
   SYM(int (*)(), get_count);
   SYM(uint64_t(*)(), get_last_type_id);
diff --git a/tests/fortify_compilation_test.cpp b/tests/fortify_compilation_test.cpp
index d859ef1..7517fde 100644
--- a/tests/fortify_compilation_test.cpp
+++ b/tests/fortify_compilation_test.cpp
@@ -376,6 +376,7 @@
   // This is fine.
   realpath(".", NULL);
 
-  // FIXME: But we should warn on this.
-  realpath(NULL, buf);
+  char bigbuf[PATH_MAX];
+  // CLANG: error: 'realpath': NULL path is never correct; flipped arguments?
+  realpath(NULL, bigbuf);
 }
diff --git a/tests/stdlib_test.cpp b/tests/stdlib_test.cpp
index c724f74..7d2dc20 100644
--- a/tests/stdlib_test.cpp
+++ b/tests/stdlib_test.cpp
@@ -184,7 +184,9 @@
 
 TEST(stdlib, realpath__NULL_filename) {
   errno = 0;
-  char* p = realpath(NULL, NULL);
+  // Work around the compile-time error generated by FORTIFY here.
+  const char* path = NULL;
+  char* p = realpath(path, NULL);
   ASSERT_TRUE(p == NULL);
   ASSERT_EQ(EINVAL, errno);
 }
diff --git a/tools/versioner/src/Driver.cpp b/tools/versioner/src/Driver.cpp
index a094818..8a8e00a 100644
--- a/tools/versioner/src/Driver.cpp
+++ b/tools/versioner/src/Driver.cpp
@@ -119,7 +119,14 @@
 
   cmd.push_back("-DANDROID");
   cmd.push_back("-D__ANDROID_API__="s + std::to_string(type.api_level));
+  // FIXME: Re-enable FORTIFY properly once our clang in external/ is new enough
+  // to support diagnose_if without giving us syntax errors.
+#if 0
   cmd.push_back("-D_FORTIFY_SOURCE=2");
+#else
+  cmd.push_back("-D_FORTIFY_SOURCE=0");
+  cmd.push_back("-D__BIONIC_DECLARE_FORTIFY_HELPERS");
+#endif
   cmd.push_back("-D_GNU_SOURCE");
   cmd.push_back("-D_FILE_OFFSET_BITS="s + std::to_string(type.file_offset_bits));
 
diff --git a/tools/versioner/src/Preprocessor.cpp b/tools/versioner/src/Preprocessor.cpp
index 757a392..a7f289b 100644
--- a/tools/versioner/src/Preprocessor.cpp
+++ b/tools/versioner/src/Preprocessor.cpp
@@ -300,7 +300,7 @@
     };
 
     auto nextCol = [&file_lines, &current_location, &nextLine]() {
-      if (current_location.column == file_lines[current_location.column - 1].length()) {
+      if (current_location.column == file_lines[current_location.line - 1].length()) {
         nextLine();
       } else {
         ++current_location.column;