diff --git a/libc/Android.bp b/libc/Android.bp
index b86313c..1e65fea 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -2307,6 +2307,7 @@
     },
     whole_static_libs: [
         "libarm-optimized-routines-mem",
+        "libc_netbsd",
     ],
     system_shared_libs: [],
     nocrt: true,
diff --git a/libc/include/android/legacy_stdlib_inlines.h b/libc/include/android/legacy_stdlib_inlines.h
index 452bed5..e9b606a 100644
--- a/libc/include/android/legacy_stdlib_inlines.h
+++ b/libc/include/android/legacy_stdlib_inlines.h
@@ -31,45 +31,6 @@
 #include <sys/cdefs.h>
 
 
-
-#if __ANDROID_API__ < 21
-
-#include <errno.h>
-#include <float.h>
-#include <stdlib.h>
-
-__BEGIN_DECLS
-
-static __inline float strtof(const char* nptr, char** endptr) {
-  // N.B. Double-rounding makes this function incorrect for some inputs.
-  double d = strtod(nptr, endptr);
-  if (__builtin_isfinite(d) && __builtin_fabs(d) > FLT_MAX) {
-    errno = ERANGE;
-    return __builtin_copysign(__builtin_huge_valf(), d);
-  }
-  return __BIONIC_CAST(static_cast, float, d);
-}
-
-static __inline double atof(const char *nptr) { return (strtod(nptr, NULL)); }
-
-static __inline int rand(void) { return (int)lrand48(); }
-
-static __inline void srand(unsigned int __s) { srand48(__s); }
-
-static __inline long random(void) { return lrand48(); }
-
-static __inline void srandom(unsigned int __s) { srand48(__s); }
-
-static __inline int grantpt(int __fd __attribute((unused))) {
-  return 0; /* devpts does this all for us! */
-}
-
-__END_DECLS
-
-#endif
-
-
-
 #if __ANDROID_API__ < 26
 
 #include <stdlib.h>
diff --git a/libc/include/err.h b/libc/include/err.h
index e91dac9..af44514 100644
--- a/libc/include/err.h
+++ b/libc/include/err.h
@@ -50,7 +50,7 @@
  *
  * New code should consider error() in `<error.h>`.
  */
-__noreturn void err(int __status, const char* __fmt, ...) __printflike(2, 3);
+__noreturn void err(int __status, const char* _Nullable __fmt, ...) __printflike(2, 3);
 
 /**
  * [verr(3)](http://man7.org/linux/man-pages/man3/verr.3.html) outputs the program name,
@@ -60,7 +60,7 @@
  *
  * New code should consider error() in `<error.h>`.
  */
-__noreturn void verr(int __status, const char* __fmt, va_list __args) __printflike(2, 0);
+__noreturn void verr(int __status, const char* _Nullable __fmt, va_list __args) __printflike(2, 0);
 
 /**
  * [errx(3)](http://man7.org/linux/man-pages/man3/errx.3.html) outputs the program name, and
@@ -70,7 +70,7 @@
  *
  * New code should consider error() in `<error.h>`.
  */
-__noreturn void errx(int __status, const char* __fmt, ...) __printflike(2, 3);
+__noreturn void errx(int __status, const char* _Nullable __fmt, ...) __printflike(2, 3);
 
 /**
  * [verrx(3)](http://man7.org/linux/man-pages/man3/err.3.html) outputs the program name, and
@@ -80,7 +80,7 @@
  *
  * New code should consider error() in `<error.h>`.
  */
-__noreturn void verrx(int __status, const char* __fmt, va_list __args) __printflike(2, 0);
+__noreturn void verrx(int __status, const char* _Nullable __fmt, va_list __args) __printflike(2, 0);
 
 /**
  * [warn(3)](http://man7.org/linux/man-pages/man3/warn.3.html) outputs the program name,
@@ -88,7 +88,7 @@
  *
  * New code should consider error() in `<error.h>`.
  */
-void warn(const char* __fmt, ...) __printflike(1, 2);
+void warn(const char* _Nullable __fmt, ...) __printflike(1, 2);
 
 /**
  * [vwarn(3)](http://man7.org/linux/man-pages/man3/vwarn.3.html) outputs the program name,
@@ -96,7 +96,7 @@
  *
  * New code should consider error() in `<error.h>`.
  */
-void vwarn(const char* __fmt, va_list __args) __printflike(1, 0);
+void vwarn(const char* _Nullable __fmt, va_list __args) __printflike(1, 0);
 
 /**
  * [warnx(3)](http://man7.org/linux/man-pages/man3/warnx.3.html) outputs the program name, and
@@ -104,7 +104,7 @@
  *
  * New code should consider error() in `<error.h>`.
  */
-void warnx(const char* __fmt, ...) __printflike(1, 2);
+void warnx(const char* _Nullable __fmt, ...) __printflike(1, 2);
 
 /**
  * [vwarnx(3)](http://man7.org/linux/man-pages/man3/warn.3.html) outputs the program name, and
@@ -112,6 +112,6 @@
  *
  * New code should consider error() in `<error.h>`.
  */
-void vwarnx(const char* __fmt, va_list __args) __printflike(1, 0);
+void vwarnx(const char* _Nullable __fmt, va_list __args) __printflike(1, 0);
 
 __END_DECLS
diff --git a/libc/include/errno.h b/libc/include/errno.h
index ab56bb3..12ebdf7 100644
--- a/libc/include/errno.h
+++ b/libc/include/errno.h
@@ -49,7 +49,7 @@
  *
  * @private
  */
-int* __errno(void) __attribute_const__;
+int* _Nonnull __errno(void) __attribute_const__;
 
 /**
  * [errno(3)](http://man7.org/linux/man-pages/man3/errno.3.html) is the last error on the calling
diff --git a/libc/include/error.h b/libc/include/error.h
index 036a831..187ee17 100644
--- a/libc/include/error.h
+++ b/libc/include/error.h
@@ -44,7 +44,7 @@
  *
  * Available since API level 23.
  */
-extern void (*error_print_progname)(void) __INTRODUCED_IN(23);
+extern void (* _Nullable error_print_progname)(void) __INTRODUCED_IN(23);
 
 /**
  * [error_message_count(3)](http://man7.org/linux/man-pages/man3/error_message_count.3.html) is
@@ -70,7 +70,7 @@
  *
  * Available since API level 23.
  */
-void error(int __status, int __errno, const char* __fmt, ...) __printflike(3, 4) __INTRODUCED_IN(23);
+void error(int __status, int __errno, const char* _Nonnull __fmt, ...) __printflike(3, 4) __INTRODUCED_IN(23);
 
 /**
  * [error_at_line(3)](http://man7.org/linux/man-pages/man3/error_at_line.3.html) formats the given
@@ -80,6 +80,6 @@
  *
  * Available since API level 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);
+void error_at_line(int __status, int __errno, const char* _Nonnull __filename, unsigned int __line_number, const char* _Nonnull __fmt, ...) __printflike(5, 6) __INTRODUCED_IN(23);
 
 __END_DECLS
diff --git a/libc/include/ftw.h b/libc/include/ftw.h
index a289643..c5fa4de 100644
--- a/libc/include/ftw.h
+++ b/libc/include/ftw.h
@@ -55,10 +55,10 @@
 };
 
 __BEGIN_DECLS
-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* __dir_path, int (*__callback)(const char*, const struct stat64*, int), int __max_fd_count) __RENAME_STAT64(ftw, 17, 21);
-int nftw64(const char* __dir_path, int (*__callback)(const char*, const struct stat64*, int, struct FTW*), int __max_fd_count, int __flags) __RENAME_STAT64(nftw, 17, 21);
+int ftw(const char* _Nonnull __dir_path, int (* _Nonnull __callback)(const char* _Nonnull, const struct stat* _Nonnull, int), int __max_fd_count) __INTRODUCED_IN(17);
+int nftw(const char* _Nonnull __dir_path, int (* _Nonnull __callback)(const char* _Nonnull, const struct stat* _Nonnull, int, struct FTW* _Nonnull), int __max_fd_count, int __flags) __INTRODUCED_IN(17);
+int ftw64(const char* _Nonnull __dir_path, int (* _Nonnull __callback)(const char* _Nonnull, const struct stat64* _Nonnull, int), int __max_fd_count) __RENAME_STAT64(ftw, 17, 21);
+int nftw64(const char* _Nonnull __dir_path, int (* _Nonnull __callback)(const char* _Nonnull, const struct stat64* _Nonnull, int, struct FTW* _Nonnull), int __max_fd_count, int __flags) __RENAME_STAT64(nftw, 17, 21);
 __END_DECLS
 
 #endif
diff --git a/libc/include/iconv.h b/libc/include/iconv.h
index ec4bdea..7cf36dc 100644
--- a/libc/include/iconv.h
+++ b/libc/include/iconv.h
@@ -54,7 +54,7 @@
  *
  * Available since API level 28.
  */
-iconv_t iconv_open(const char* __src_encoding, const char* __dst_encoding) __INTRODUCED_IN(28);
+iconv_t _Nonnull iconv_open(const char* _Nonnull __src_encoding, const char* _Nonnull __dst_encoding) __INTRODUCED_IN(28);
 
 /**
  * [iconv(3)](http://man7.org/linux/man-pages/man3/iconv.3.html) converts characters from one
@@ -68,7 +68,7 @@
  *
  * Available since API level 28.
  */
-size_t iconv(iconv_t __converter, char** __src_buf, size_t* __src_bytes_left, char** __dst_buf, size_t* __dst_bytes_left) __INTRODUCED_IN(28);
+size_t iconv(iconv_t _Nonnull __converter, char* _Nullable * _Nullable __src_buf, size_t* __BIONIC_COMPLICATED_NULLNESS __src_bytes_left, char* _Nullable * _Nullable __dst_buf, size_t* __BIONIC_COMPLICATED_NULLNESS __dst_bytes_left) __INTRODUCED_IN(28);
 
 /**
  * [iconv_close(3)](http://man7.org/linux/man-pages/man3/iconv_close.3.html) deallocates a converter
@@ -78,6 +78,6 @@
  *
  * Available since API level 28.
  */
-int iconv_close(iconv_t __converter) __INTRODUCED_IN(28);
+int iconv_close(iconv_t _Nonnull __converter) __INTRODUCED_IN(28);
 
 __END_DECLS
diff --git a/libc/include/stdlib.h b/libc/include/stdlib.h
index c185ec7..b416f62 100644
--- a/libc/include/stdlib.h
+++ b/libc/include/stdlib.h
@@ -163,17 +163,8 @@
 
 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);
 #define MB_CUR_MAX __ctype_get_mb_cur_max()
-#else
-/*
- * Pre-L we didn't have any locale support and so we were always the POSIX
- * locale. POSIX specifies that MB_CUR_MAX for the POSIX locale is 1:
- * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/stdlib.h.html
- */
-#define MB_CUR_MAX 1
-#endif
 
 #if defined(__BIONIC_INCLUDE_FORTIFY_HEADERS)
 #include <bits/fortify/stdlib.h>
@@ -183,7 +174,6 @@
 long labs(long __x) __attribute_const__ __INTRODUCED_IN(19);
 long long llabs(long long __x) __attribute_const__ __INTRODUCED_IN(19);
 
-#if __ANDROID_API__ >= 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);
@@ -195,9 +185,6 @@
 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* _Nonnull __s, char* _Nullable * _Nullable __end_ptr, locale_t _Nonnull __l) __INTRODUCED_IN(26);