Merge "Remove obsolete hacks for the fabs() family."
diff --git a/docs/status.md b/docs/status.md
index 20a1309..5d2603a 100644
--- a/docs/status.md
+++ b/docs/status.md
@@ -36,13 +36,17 @@
   * `<monetary.h>`. See
     [discussion](https://github.com/android/ndk/issues/1182).
   * `<wordexp.h>`
+  * Locales. Although bionic contains the various `_l()` functions, the only
+    locale supported is a UTF-8 C/POSIX locale. Most of the POSIX APIs are
+    insufficient to support the wide range of languages used by Android users,
+    and apps should use icu4c (or do their i18n work in Java) instead.
+  * Robust mutexes. See
+    [discussion](https://github.com/android/ndk/issues/1181).
   * Thread cancellation (`pthread_cancel`). Unlikely to ever be implemented
     because of the difficulty and cost of implementing it, and the difficulty
     of using it correctly. See
     [This is why we can't have safe cancellation points](https://lwn.net/Articles/683118/)
     for more about thread cancellation.
-  * Robust mutexes. See
-    [discussion](https://github.com/android/ndk/issues/1181).
 
 Run `./libc/tools/check-symbols-glibc.py` in bionic/ for the current
 list of POSIX functions implemented by glibc but not by bionic.
diff --git a/libc/SECCOMP_ALLOWLIST_COMMON.TXT b/libc/SECCOMP_ALLOWLIST_COMMON.TXT
index a4218ee..efbf28b 100644
--- a/libc/SECCOMP_ALLOWLIST_COMMON.TXT
+++ b/libc/SECCOMP_ALLOWLIST_COMMON.TXT
@@ -3,60 +3,60 @@
 #
 # This file is processed by a python script named genseccomp.py.
 
-# syscalls needed to boot android
-int	pivot_root:pivot_root(const char *new_root, const char *put_old)	lp64
-int	ioprio_get:ioprio_get(int which, int who)	lp64
-int	ioprio_set:ioprio_set(int which, int who, int ioprio)	lp64
-pid_t	gettid:gettid()	all
-int	futex:futex(int *uaddr, int futex_op, int val, const struct timespec *timeout, int *uaddr2, int val3)	all
-int	clone:clone(int (*fn)(void *), void *child_stack, int flags, void *arg, ..) all
-int	sigreturn:sigreturn(unsigned long __unused)	lp32
-int	rt_sigreturn:rt_sigreturn(unsigned long __unused)	all
-int	rt_tgsigqueueinfo:int rt_tgsigqueueinfo(pid_t tgid, pid_t tid, int sig, siginfo_t *uinfo)	all
-int	restart_syscall:int restart_syscall()	all
+# Syscalls needed to boot android
+int	pivot_root(const char*, const char*)	lp64
+int	ioprio_get(int, int)	lp64
+int	ioprio_set(int, int, int)	lp64
 
-# vfork is used by java.lang.ProcessBuilder
-pid_t	vfork:vfork()	arm,x86,x86_64
+# Syscalls used internally by bionic, but not exposed directly.
+pid_t	gettid()	all
+int	futex(int*, int, int, const timespec*, int*, int)	all
+int	clone(int (*)(void*), void*, int, void*, ...) all
+int	sigreturn(unsigned long)	lp32
+int	rt_sigreturn(unsigned long)	all
+int	rt_tgsigqueueinfo(pid_t, pid_t, int, siginfo_t*)	all
+int	restart_syscall()	all
 
-# Needed for performance tools
-int	perf_event_open:perf_event_open(struct perf_event_attr *attr, pid_t pid, int cpu, int group_fd, unsigned long flags)	all
+# vfork is used by bionic (and java.lang.ProcessBuilder) on some
+# architectures. (The others use clone(2) directly instead.)
+pid_t	vfork()	arm,x86,x86_64
 
-# Needed for strace
-int	tkill:tkill(int tid, int sig)	all
+# Needed for performance tools.
+int	perf_event_open(perf_event_attr*, pid_t, int, int, unsigned long)	all
 
-# b/34763393
-int	seccomp:seccomp(unsigned int operation, unsigned int flags, void *args)	all
+# Needed for strace.
+int	tkill(int, int)	all
 
-# Needed by sanitizers (b/34606909, b/136777266).
-int open:open(const char*, int, ...)  arm,x86,x86_64
-int stat64:stat64(const char*, struct stat64*)  arm,x86
-ssize_t readlink:readlink(const char*, char*, size_t)  arm,x86,x86_64
-# Needed by ubsan in T? (http://b/229989971)
-int stat(const char*, struct stat*)  arm,x86,x86_64
+# Needed for a CTS test of seccomp (b/34763393).
+int	seccomp(unsigned, unsigned, void*)	all
+
+# TODO: remove these now we've updated the toolchain (http://b/229989971).
+int open(const char*, int, ...)  arm,x86,x86_64
+int stat64(const char*, stat64*)  arm,x86
+ssize_t readlink(const char*, char*, size_t)  arm,x86,x86_64
+int stat(const char*, stat*)  arm,x86,x86_64
 
 #
-# Useful new syscalls which we don't yet use in bionic.
+# (Potentially) useful new syscalls which we don't yet use in bionic.
 #
 
 # Since Linux 2.5, not in glibc.
-int io_setup(unsigned nr, aio_context_t *ctxp) all
-int io_destroy(aio_context_t ctx) all
-int io_submit(aio_context_t ctx, long nr,  struct iocb **iocbpp) all
-int io_getevents(aio_context_t ctx, long min_nr, long max_nr, struct io_event *events, struct timespec *timeout) all
-int io_cancel(aio_context_t ctx, struct iocb *, struct io_event *result) all
+int io_setup(unsigned, aio_context_t*) all
+int io_destroy(aio_context_t) all
+int io_submit(aio_context_t, long,  iocb**) all
+int io_getevents(aio_context_t, long, long, io_event*, timespec*) all
+int io_cancel(aio_context_t, iocb*, io_event*) all
 # Since Linux 3.14, not in glibc.
-int sched_getattr(pid_t pid, struct sched_attr* attr, unsigned int flags) all
-int sched_setattr(pid_t pid, struct sched_attr* attr, unsigned int size, unsigned int flags) all
+int sched_getattr(pid_t, sched_attr*, unsigned) all
+int sched_setattr(pid_t, sched_attr*, unsigned, unsigned) all
 # Since Linux 3.19, not in glibc (and not really needed to implement fexecve).
-int execveat(int dirfd, const char* pathname, char* const* argv, char* const* envp, int flags)  all
+int execveat(int, const char*, char* const*, char* const*, int)  all
 # Since Linux 4.3, not in glibc. Probed for and conditionally used by ART.
-int membarrier(int cmd, int flags) all
-# Since Linux 4.5, glibc 2.27.
-ssize_t copy_file_range(int fd_in, loff_t* off_in, int fd_out, loff_t* off_out, size_t len, unsigned int flags) all
-# Since Linux 4.6, glibc 2.26.
-ssize_t preadv2(int fd, const struct iovec* iov, int iovcnt, off_t offset, int flags) all
-ssize_t pwritev2(int fd, const struct iovec* iov, int iovcnt, off_t offset, int flags) all
-# Since Linux 5.1, not in glibc.
+int membarrier(int, int) all
+# Since Linux 5.1, not in glibc. Not used by bionic, and not likely ever
+# to be (because the last thing anyone needs is a new 32-bit ABI in the
+# 2020s!) but http://b/138781460 showed cuttlefish needed at least the
+# clock_gettime64 syscall.
 int clock_gettime64(clockid_t, timespec64*) lp32
 int clock_settime64(clockid_t, const timespec64*) lp32
 int clock_adjtime64(clockid_t, timex64*) lp32
@@ -70,7 +70,6 @@
 int pselect6_time64(int, fd_set*, fd_set*, timespec64*, void*) lp32
 int ppoll_time64(pollfd*, unsigned int, timespec64*, const sigset64_t*, size_t) lp32
 int recvmmsg_time64(int, mmsghdr*, unsigned int, int, const timespec64*) lp32
-int semtimedop_time64(int, sembuf*, size_t, const timespec64*) lp32
 int rt_sigtimedwait_time64(const sigset64_t*, siginfo_t*, const timespec64*, size_t) lp32
 int futex_time64(int*, int, int, const timespec64*, int*, int) lp32
 int sched_rr_get_interval_time64(pid_t, timespec64*) lp32
diff --git a/libc/include/stdlib.h b/libc/include/stdlib.h
index 4aa27f9..06ed3f4 100644
--- a/libc/include/stdlib.h
+++ b/libc/include/stdlib.h
@@ -49,82 +49,82 @@
 __noreturn void _Exit(int) __RENAME(_exit);
 #endif
 
-int atexit(void (*__fn)(void));
+int atexit(void (* _Nonnull __fn)(void));
 
-int at_quick_exit(void (*__fn)(void)) __INTRODUCED_IN(21);
+int at_quick_exit(void (* _Nonnull __fn)(void)) __INTRODUCED_IN(21);
 void quick_exit(int __status) __noreturn __INTRODUCED_IN(21);
 
-char* getenv(const char* __name);
-int putenv(char* __assignment);
-int setenv(const char* __name, const char* __value, int __overwrite);
-int unsetenv(const char* __name);
+char* _Nullable getenv(const char* _Nonnull __name);
+int putenv(char* _Nonnull __assignment);
+int setenv(const char* _Nonnull __name, const char* _Nonnull __value, int __overwrite);
+int unsetenv(const char* _Nonnull __name);
 int clearenv(void);
 
-char* mkdtemp(char* __template);
-char* mktemp(char* __template) __attribute__((deprecated("mktemp is unsafe, use mkstemp or tmpfile instead")));
+char* _Nullable mkdtemp(char* _Nonnull __template);
+char* _Nullable mktemp(char* _Nonnull __template) __attribute__((deprecated("mktemp is unsafe, use mkstemp or tmpfile instead")));
 
-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);
+int mkostemp64(char* _Nonnull __template, int __flags) __INTRODUCED_IN(23);
+int mkostemp(char* _Nonnull __template, int __flags) __INTRODUCED_IN(23);
+int mkostemps64(char* _Nonnull __template, int __suffix_length, int __flags) __INTRODUCED_IN(23);
+int mkostemps(char* _Nonnull __template, int __suffix_length, int __flags) __INTRODUCED_IN(23);
+int mkstemp64(char* _Nonnull __template) __INTRODUCED_IN(21);
+int mkstemp(char* _Nonnull __template);
+int mkstemps64(char* _Nonnull __template, int __flags) __INTRODUCED_IN(23);
+int mkstemps(char* _Nonnull __template, int __flags);
 
-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);
+long strtol(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, int __base);
+long long strtoll(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, int __base);
+unsigned long strtoul(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, int __base);
+unsigned long long strtoull(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, int __base);
 
-int posix_memalign(void** __memptr, size_t __alignment, size_t __size) __INTRODUCED_IN(17);
+int posix_memalign(void* _Nullable * _Nullable __memptr, size_t __alignment, size_t __size) __INTRODUCED_IN(17);
 
-void* aligned_alloc(size_t __alignment, size_t __size) __INTRODUCED_IN(28);
+void* _Nullable aligned_alloc(size_t __alignment, size_t __size) __INTRODUCED_IN(28);
 
-double strtod(const char* __s, char** __end_ptr);
-long double strtold(const char* __s, char** __end_ptr) __RENAME_LDBL(strtod, 3, 21);
+double strtod(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr);
+long double strtold(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr) __RENAME_LDBL(strtod, 3, 21);
 
-unsigned long strtoul_l(const char* __s, char** __end_ptr, int __base, locale_t __l) __INTRODUCED_IN(26);
+unsigned long strtoul_l(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, int __base, locale_t _Nonnull __l) __INTRODUCED_IN(26);
 
-int atoi(const char* __s) __attribute_pure__;
-long atol(const char* __s) __attribute_pure__;
-long long atoll(const char* __s) __attribute_pure__;
+int atoi(const char* _Nonnull __s) __attribute_pure__;
+long atol(const char* _Nonnull __s) __attribute_pure__;
+long long atoll(const char* _Nonnull __s) __attribute_pure__;
 
-__wur char* realpath(const char* __path, char* __resolved);
-int system(const char* __command);
+__wur char* _Nullable realpath(const char* _Nonnull __path, char* _Nullable __resolved);
+int system(const char* _Nonnull __command);
 
-void* bsearch(const void* __key, const void* __base, size_t __nmemb, size_t __size, int (*__comparator)(const void* __lhs, const void* __rhs));
+void* _Nullable bsearch(const void* _Nonnull __key, const void* _Nullable __base, size_t __nmemb, size_t __size, int (* _Nonnull __comparator)(const void* _Nonnull __lhs, const void* _Nonnull __rhs));
 
-void qsort(void* __base, size_t __nmemb, size_t __size, int (*__comparator)(const void* __lhs, const void* __rhs));
+void qsort(void* _Nullable __base, size_t __nmemb, size_t __size, int (* _Nonnull __comparator)(const void* _Nonnull __lhs, const void* _Nonnull __rhs));
 
 uint32_t arc4random(void);
 uint32_t arc4random_uniform(uint32_t __upper_bound);
-void arc4random_buf(void* __buf, size_t __n);
+void arc4random_buf(void* _Nonnull __buf, size_t __n);
 
 #define RAND_MAX 0x7fffffff
 
-int rand_r(unsigned int* __seed_ptr) __INTRODUCED_IN(21);
+int rand_r(unsigned int* _Nonnull __seed_ptr) __INTRODUCED_IN(21);
 
 double drand48(void);
-double erand48(unsigned short __xsubi[3]);
-long jrand48(unsigned short __xsubi[3]);
-void lcong48(unsigned short __param[7]) __INTRODUCED_IN(23);
+double erand48(unsigned short __xsubi[_Nonnull 3]);
+long jrand48(unsigned short __xsubi[_Nonnull 3]);
+void lcong48(unsigned short __param[_Nonnull 7]) __INTRODUCED_IN(23);
 long lrand48(void);
 long mrand48(void);
-long nrand48(unsigned short __xsubi[3]);
-unsigned short* seed48(unsigned short __seed16v[3]);
+long nrand48(unsigned short __xsubi[_Nonnull 3]);
+unsigned short* _Nonnull seed48(unsigned short __seed16v[_Nonnull 3]);
 void srand48(long __seed);
 
-char* initstate(unsigned int __seed, char* __state, size_t __n) __INTRODUCED_IN(21);
-char* setstate(char* __state) __INTRODUCED_IN(21);
+char* _Nullable initstate(unsigned int __seed, char* _Nonnull __state, size_t __n) __INTRODUCED_IN(21);
+char* _Nullable setstate(char* _Nonnull __state) __INTRODUCED_IN(21);
 
 int getpt(void);
 int posix_openpt(int __flags) __INTRODUCED_IN(21);
-char* ptsname(int __fd);
-int ptsname_r(int __fd, char* __buf, size_t __n);
+char* _Nullable ptsname(int __fd);
+int ptsname_r(int __fd, char* _Nonnull __buf, size_t __n);
 int unlockpt(int __fd);
 
-int getsubopt(char** __option, char* const* __tokens, char** __value_ptr) __INTRODUCED_IN(26);
+int getsubopt(char* _Nonnull * _Nonnull __option, char* _Nonnull const* _Nonnull __tokens, char* _Nullable * _Nonnull __value_ptr) __INTRODUCED_IN(26);
 
 typedef struct {
   int quot;
@@ -154,18 +154,18 @@
  *
  * Returns the number of samples written to `__averages` (at most 3), and returns -1 on failure.
  */
-int getloadavg(double __averages[], int __n) __INTRODUCED_IN(29);
+int getloadavg(double __averages[_Nonnull], int __n) __INTRODUCED_IN(29);
 
 /* BSD compatibility. */
-const char* getprogname(void) __INTRODUCED_IN(21);
-void setprogname(const char* __name) __INTRODUCED_IN(21);
+const char* _Nullable getprogname(void) __INTRODUCED_IN(21);
+void setprogname(const char* _Nonnull __name) __INTRODUCED_IN(21);
 
-int mblen(const char* __s, size_t __n) __INTRODUCED_IN_NO_GUARD_FOR_NDK(26);
-size_t mbstowcs(wchar_t* __dst, const char* __src, size_t __n) __INTRODUCED_IN_NO_GUARD_FOR_NDK(21);
-int mbtowc(wchar_t* __wc_ptr, const char* __s, size_t __n) __INTRODUCED_IN_NO_GUARD_FOR_NDK(21);
-int wctomb(char* __dst, wchar_t __wc) __INTRODUCED_IN_NO_GUARD_FOR_NDK(21);
+int mblen(const char* _Nullable __s, size_t __n) __INTRODUCED_IN_NO_GUARD_FOR_NDK(26);
+size_t mbstowcs(wchar_t* _Nullable __dst, const char* _Nullable __src, size_t __n) __INTRODUCED_IN_NO_GUARD_FOR_NDK(21);
+int mbtowc(wchar_t* _Nullable __wc_ptr, const char*  _Nullable __s, size_t __n) __INTRODUCED_IN_NO_GUARD_FOR_NDK(21);
+int wctomb(char* _Nullable __dst, wchar_t __wc) __INTRODUCED_IN_NO_GUARD_FOR_NDK(21);
 
-size_t wcstombs(char* __dst, const wchar_t* __src, size_t __n) __INTRODUCED_IN_NO_GUARD_FOR_NDK(21);
+size_t wcstombs(char* _Nullable __dst, const wchar_t* _Nullable __src, size_t __n) __INTRODUCED_IN_NO_GUARD_FOR_NDK(21);
 
 #if __ANDROID_API__ >= 21
 size_t __ctype_get_mb_cur_max(void) __INTRODUCED_IN(21);
@@ -192,25 +192,25 @@
 #endif
 
 #if __ANDROID_API__ >= 21
-float strtof(const char* __s, char** __end_ptr) __INTRODUCED_IN(21);
-double atof(const char* __s) __attribute_pure__ __INTRODUCED_IN(21);
+float strtof(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr) __INTRODUCED_IN(21);
+double atof(const char* _Nonnull __s) __attribute_pure__ __INTRODUCED_IN(21);
 int rand(void) __INTRODUCED_IN(21);
 void srand(unsigned int __seed) __INTRODUCED_IN(21);
 long random(void) __INTRODUCED_IN(21);
 void srandom(unsigned int __seed) __INTRODUCED_IN(21);
 int grantpt(int __fd) __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);
+long long strtoll_l(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, int __base, locale_t _Nonnull __l) __INTRODUCED_IN(21);
+unsigned long long strtoull_l(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, int __base, locale_t _Nonnull __l) __INTRODUCED_IN(21);
+long double strtold_l(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, locale_t _Nonnull __l) __INTRODUCED_IN(21);
 #else
 // Implemented as static inlines before 21.
 #endif
 
 #if __ANDROID_API__ >= 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);
+double strtod_l(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, locale_t _Nonnull __l) __INTRODUCED_IN(26);
+float strtof_l(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, locale_t _Nonnull __l) __INTRODUCED_IN(26);
+long strtol_l(const char* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, int, locale_t _Nonnull __l) __INTRODUCED_IN(26);
 #else
 // Implemented as static inlines before 26.
 #endif
diff --git a/tests/clang_fortify_tests.cpp b/tests/clang_fortify_tests.cpp
index 40cb83f..544af43 100644
--- a/tests/clang_fortify_tests.cpp
+++ b/tests/clang_fortify_tests.cpp
@@ -387,6 +387,8 @@
 }
 
 static void testStdlib() {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnonnull"
   char path_buffer[PATH_MAX - 1];
   // expected-warning@+2{{ignoring return value of function}}
   // expected-error@+1{{must be NULL or a pointer to a buffer with >= PATH_MAX bytes}}
@@ -401,6 +403,7 @@
   // expected-warning@+2{{ignoring return value of function}}
   // expected-error@+1{{flipped arguments?}}
   realpath(nullptr, nullptr);
+#pragma clang diagnostic pop
 }
 }  // namespace compilation_tests
 #endif
diff --git a/tests/stdlib_test.cpp b/tests/stdlib_test.cpp
index f507e08..45169e3 100644
--- a/tests/stdlib_test.cpp
+++ b/tests/stdlib_test.cpp
@@ -494,7 +494,10 @@
 TEST(stdlib, system_NULL) {
   // "The system() function shall always return non-zero when command is NULL."
   // http://pubs.opengroup.org/onlinepubs/9699919799/functions/system.html
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnonnull"
   ASSERT_NE(0, system(nullptr));
+#pragma clang diagnostic pop
 }
 
 // https://austingroupbugs.net/view.php?id=1440
diff --git a/tests/unistd_test.cpp b/tests/unistd_test.cpp
index 5fce5b8..2a36460 100644
--- a/tests/unistd_test.cpp
+++ b/tests/unistd_test.cpp
@@ -294,10 +294,13 @@
 }
 
 TEST(UNISTD_TEST, setenv_EINVAL) {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnonnull"
   EXPECT_EQ(-1, setenv(nullptr, "value", 0));
   EXPECT_EQ(EINVAL, errno);
   EXPECT_EQ(-1, setenv(nullptr, "value", 1));
   EXPECT_EQ(EINVAL, errno);
+#pragma clang diagnostic pop
   EXPECT_EQ(-1, setenv("", "value", 0));
   EXPECT_EQ(EINVAL, errno);
   EXPECT_EQ(-1, setenv("", "value", 1));