diff --git a/libc/include/android/legacy_errno_inlines.h b/libc/include/android/legacy_errno_inlines.h
new file mode 100644
index 0000000..71096fc
--- /dev/null
+++ b/libc/include/android/legacy_errno_inlines.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _ANDROID_LEGACY_ERRNO_INLINES_H
+#define _ANDROID_LEGACY_ERRNO_INLINES_H
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+static __inline int __attribute__((deprecated)) __set_errno(int n) {
+  errno = n;
+  return -1;
+}
+
+__END_DECLS
+
+#endif /* _ANDROID_LEGACY_ERRNO_INLINES_H */
diff --git a/libc/include/android/legacy_signal_inlines.h b/libc/include/android/legacy_signal_inlines.h
new file mode 100644
index 0000000..1b6e687
--- /dev/null
+++ b/libc/include/android/legacy_signal_inlines.h
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _ANDROID_LEGACY_SIGNAL_INLINES_H_
+#define _ANDROID_LEGACY_SIGNAL_INLINES_H_
+
+#include <string.h>
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+extern sighandler_t bsd_signal(int signum, sighandler_t handler);
+
+static __inline int sigismember(sigset_t *set, int signum) {
+  /* Signal numbers start at 1, but bit positions start at 0. */
+  int bit = signum - 1;
+  const unsigned long *local_set = (const unsigned long *)set;
+  if (set == NULL || bit < 0 || bit >= (int)(8 * sizeof(sigset_t))) {
+    errno = EINVAL;
+    return -1;
+  }
+  return (int)((local_set[bit / LONG_BIT] >> (bit % LONG_BIT)) & 1);
+}
+
+static __inline int sigaddset(sigset_t *set, int signum) {
+  /* Signal numbers start at 1, but bit positions start at 0. */
+  int bit = signum - 1;
+  unsigned long *local_set = (unsigned long *)set;
+  if (set == NULL || bit < 0 || bit >= (int)(8 * sizeof(sigset_t))) {
+    errno = EINVAL;
+    return -1;
+  }
+  local_set[bit / LONG_BIT] |= 1UL << (bit % LONG_BIT);
+  return 0;
+}
+
+static __inline int sigdelset(sigset_t *set, int signum) {
+  /* Signal numbers start at 1, but bit positions start at 0. */
+  int bit = signum - 1;
+  unsigned long *local_set = (unsigned long *)set;
+  if (set == NULL || bit < 0 || bit >= (int)(8 * sizeof(sigset_t))) {
+    errno = EINVAL;
+    return -1;
+  }
+  local_set[bit / LONG_BIT] &= ~(1UL << (bit % LONG_BIT));
+  return 0;
+}
+
+static __inline int sigemptyset(sigset_t *set) {
+  if (set == NULL) {
+    errno = EINVAL;
+    return -1;
+  }
+  memset(set, 0, sizeof(sigset_t));
+  return 0;
+}
+
+static __inline int sigfillset(sigset_t *set) {
+  if (set == NULL) {
+    errno = EINVAL;
+    return -1;
+  }
+  memset(set, ~0, sizeof(sigset_t));
+  return 0;
+}
+
+static __inline sighandler_t signal(int s, sighandler_t f) {
+  return bsd_signal(s, f);
+}
+
+__END_DECLS
+
+#endif /* _ANDROID_LEGACY_SIGNAL_INLINES_H_ */
diff --git a/libc/include/android/legacy_stdlib_inlines.h b/libc/include/android/legacy_stdlib_inlines.h
new file mode 100644
index 0000000..58a2a9e
--- /dev/null
+++ b/libc/include/android/legacy_stdlib_inlines.h
@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _ANDROID_LEGACY_STDLIB_INLINES_H_
+#define _ANDROID_LEGACY_STDLIB_INLINES_H_
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+static __inline float strtof(const char *nptr, char **endptr) {
+  return (float)strtod(nptr, endptr);
+}
+
+static __inline double atof(const char *nptr) { return (strtod(nptr, NULL)); }
+
+static __inline int abs(int __n) { return (__n < 0) ? -__n : __n; }
+
+static __inline long labs(long __n) { return (__n < 0L) ? -__n : __n; }
+
+static __inline long long llabs(long long __n) {
+  return (__n < 0LL) ? -__n : __n;
+}
+
+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 /* _ANDROID_LEGACY_STDLIB_INLINES_H_ */
diff --git a/libc/include/android/legacy_sys_atomics_inlines.h b/libc/include/android/legacy_sys_atomics_inlines.h
new file mode 100644
index 0000000..85cbade
--- /dev/null
+++ b/libc/include/android/legacy_sys_atomics_inlines.h
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _ANDROID_LEGACY_SYS_ATOMICS_INLINES_H_
+#define _ANDROID_LEGACY_SYS_ATOMICS_INLINES_H_
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+/* Note: atomic operations that were exported by the C library didn't
+ *       provide any memory barriers, which created potential issues on
+ *       multi-core devices. We now define them as inlined calls to
+ *       GCC sync builtins, which always provide a full barrier.
+ *
+ *       NOTE: The C library still exports atomic functions by the same
+ *              name to ensure ABI stability for existing NDK machine code.
+ *
+ *       If you are an NDK developer, we encourage you to rebuild your
+ *       unmodified sources against this header as soon as possible.
+ */
+#define __ATOMIC_INLINE__ static __inline __attribute__((always_inline))
+
+__ATOMIC_INLINE__ int __atomic_cmpxchg(int old, int _new, volatile int *ptr) {
+  /* We must return 0 on success */
+  return __sync_val_compare_and_swap(ptr, old, _new) != old;
+}
+
+__ATOMIC_INLINE__ int __atomic_swap(int _new, volatile int *ptr) {
+  int prev;
+  do {
+    prev = *ptr;
+  } while (__sync_val_compare_and_swap(ptr, prev, _new) != prev);
+  return prev;
+}
+
+__ATOMIC_INLINE__ int __atomic_dec(volatile int *ptr) {
+  return __sync_fetch_and_sub(ptr, 1);
+}
+
+__ATOMIC_INLINE__ int __atomic_inc(volatile int *ptr) {
+  return __sync_fetch_and_add(ptr, 1);
+}
+
+__END_DECLS
+
+#endif /* _ANDROID_LEGACY_SYS_ATOMICS_INLINES_H_ */
diff --git a/libc/include/android/legacy_sys_stat_inlines.h b/libc/include/android/legacy_sys_stat_inlines.h
new file mode 100644
index 0000000..f6d3c0f
--- /dev/null
+++ b/libc/include/android/legacy_sys_stat_inlines.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _ANDROID_LEGACY_SYS_STAT_INLINES_H_
+#define _ANDROID_LEGACY_SYS_STAT_INLINES_H_
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+static __inline int mkfifo(const char *__p, mode_t __m) {
+  return mknod(__p, (__m & ~S_IFMT) | S_IFIFO, (dev_t)0);
+}
+
+__END_DECLS
+
+#endif /* _ANDROID_LEGACY_SYS_STAT_INLINES_H_ */
diff --git a/libc/include/android/legacy_termios_inlines.h b/libc/include/android/legacy_termios_inlines.h
new file mode 100644
index 0000000..fb61f27
--- /dev/null
+++ b/libc/include/android/legacy_termios_inlines.h
@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _ANDROID_LEGACY_TERMIOS_INLINES_H_
+#define _ANDROID_LEGACY_TERMIOS_INLINES_H_
+
+#include <linux/termios.h>
+#include <sys/cdefs.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+
+__BEGIN_DECLS
+
+static __inline int tcgetattr(int fd, struct termios *s) {
+  return ioctl(fd, TCGETS, s);
+}
+
+static __inline int tcsetattr(int fd, int __opt, const struct termios *s) {
+  return ioctl(fd, __opt, (void *)s);
+}
+
+static __inline int tcflow(int fd, int action) {
+  return ioctl(fd, TCXONC, (void *)(intptr_t)action);
+}
+
+static __inline int tcflush(int fd, int __queue) {
+  return ioctl(fd, TCFLSH, (void *)(intptr_t)__queue);
+}
+
+static __inline pid_t tcgetsid(int fd) {
+  pid_t _pid;
+  return ioctl(fd, TIOCGSID, &_pid) ? (pid_t)-1 : _pid;
+}
+
+static __inline int tcsendbreak(int fd, int __duration) {
+  return ioctl(fd, TCSBRKP, (void *)(uintptr_t)__duration);
+}
+
+static __inline speed_t cfgetospeed(const struct termios *s) {
+  return (speed_t)(s->c_cflag & CBAUD);
+}
+
+static __inline int cfsetospeed(struct termios *s, speed_t speed) {
+  s->c_cflag = (s->c_cflag & ~CBAUD) | (speed & CBAUD);
+  return 0;
+}
+
+static __inline speed_t cfgetispeed(const struct termios *s) {
+  return (speed_t)(s->c_cflag & CBAUD);
+}
+
+static __inline int cfsetispeed(struct termios *s, speed_t speed) {
+  s->c_cflag = (s->c_cflag & ~CBAUD) | (speed & CBAUD);
+  return 0;
+}
+
+static __inline void cfmakeraw(struct termios *s) {
+  s->c_iflag &=
+      ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
+  s->c_oflag &= ~OPOST;
+  s->c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+  s->c_cflag &= ~(CSIZE | PARENB);
+  s->c_cflag |= CS8;
+}
+
+__END_DECLS
+
+#endif /* _ANDROID_LEGACY_TERMIOS_INLINES_H_ */
diff --git a/libc/include/ctype.h b/libc/include/ctype.h
index d05a952..83b5ba7 100644
--- a/libc/include/ctype.h
+++ b/libc/include/ctype.h
@@ -43,36 +43,37 @@
 #include <sys/cdefs.h>
 #include <xlocale.h>
 
-#define	_CTYPE_U	0x01
-#define	_CTYPE_L	0x02
-#define	_CTYPE_D	0x04
-#define	_CTYPE_S	0x08
-#define	_CTYPE_P	0x10
-#define	_CTYPE_C	0x20
-#define	_CTYPE_X	0x40
-#define	_CTYPE_B	0x80
-#define	_CTYPE_R	(_CTYPE_P|_CTYPE_U|_CTYPE_L|_CTYPE_D|_CTYPE_B)
-#define	_CTYPE_A	(_CTYPE_L|_CTYPE_U)
+#define _CTYPE_U 0x01
+#define _CTYPE_L 0x02
+#define _CTYPE_D 0x04
+#define _CTYPE_S 0x08
+#define _CTYPE_P 0x10
+#define _CTYPE_C 0x20
+#define _CTYPE_X 0x40
+#define _CTYPE_B 0x80
+#define _CTYPE_R (_CTYPE_P|_CTYPE_U|_CTYPE_L|_CTYPE_D|_CTYPE_B)
+#define _CTYPE_A (_CTYPE_L|_CTYPE_U)
 
 __BEGIN_DECLS
 
 extern const char	*_ctype_;
 
 #if defined(__GNUC__) || defined(_ANSI_LIBRARY) || defined(lint)
-int	isalnum(int);
-int	isalpha(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);
+int isalpha(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);
 
+#if __ANDROID_API__ >= 21
 int isalnum_l(int, locale_t);
 int isalpha_l(int, locale_t);
 int isblank_l(int, locale_t);
@@ -87,17 +88,18 @@
 int isxdigit_l(int, locale_t);
 int tolower_l(int, locale_t);
 int toupper_l(int, locale_t);
+#endif /* __ANDROID_API__ >= 21 */
 
 #if __BSD_VISIBLE || __ISO_C_VISIBLE >= 1999 || __POSIX_VISIBLE > 200112 \
     || __XPG_VISIBLE > 600
-int	isblank(int);
+int isblank(int);
 #endif
 
 #if __BSD_VISIBLE || __XPG_VISIBLE
-int	isascii(int);
-int	toascii(int);
-int	_tolower(int);
-int	_toupper(int);
+int isascii(int);
+int toascii(int);
+int _tolower(int);
+int _toupper(int);
 #endif /* __BSD_VISIBLE || __XPG_VISIBLE */
 
 #endif /* __GNUC__ || _ANSI_LIBRARY || lint */
diff --git a/libc/include/errno.h b/libc/include/errno.h
index 1a36b7a..82f4b42 100644
--- a/libc/include/errno.h
+++ b/libc/include/errno.h
@@ -46,6 +46,10 @@
 /* a macro expanding to the errno l-value */
 #define  errno   (*__errno())
 
+#if __ANDROID_API__ < 21
+#include <android/legacy_errno_inlines.h>
+#endif
+
 __END_DECLS
 
 #endif /* _ERRNO_H */
diff --git a/libc/include/signal.h b/libc/include/signal.h
index 39d37e9..554e0ac 100644
--- a/libc/include/signal.h
+++ b/libc/include/signal.h
@@ -105,15 +105,15 @@
 
 extern int sigaction(int, const struct sigaction*, struct sigaction*);
 
-extern sighandler_t signal(int, sighandler_t);
+_BIONIC_NOT_BEFORE_21(extern sighandler_t signal(int, sighandler_t);)
 
 extern int siginterrupt(int, int);
 
-extern int sigaddset(sigset_t*, int);
-extern int sigdelset(sigset_t*, int);
-extern int sigemptyset(sigset_t*);
-extern int sigfillset(sigset_t*);
-extern int sigismember(const sigset_t*, int);
+_BIONIC_NOT_BEFORE_21(extern int sigaddset(sigset_t*, int);)
+_BIONIC_NOT_BEFORE_21(extern int sigdelset(sigset_t*, int);)
+_BIONIC_NOT_BEFORE_21(extern int sigemptyset(sigset_t*);)
+_BIONIC_NOT_BEFORE_21(extern int sigfillset(sigset_t*);)
+_BIONIC_NOT_BEFORE_21(extern int sigismember(const sigset_t*, int);)
 
 extern int sigpending(sigset_t*) __nonnull((1));
 extern int sigprocmask(int, const sigset_t*, sigset_t*);
@@ -136,6 +136,10 @@
 extern int sigtimedwait(const sigset_t*, siginfo_t*, const struct timespec*);
 extern int sigwaitinfo(const sigset_t*, siginfo_t*);
 
+#if __ANDROID_API__ < 21
+#include <android/legacy_signal_inlines.h>
+#endif
+
 __END_DECLS
 
 #endif /* _SIGNAL_H_ */
diff --git a/libc/include/stdlib.h b/libc/include/stdlib.h
index 4cb288d..308007a 100644
--- a/libc/include/stdlib.h
+++ b/libc/include/stdlib.h
@@ -76,10 +76,10 @@
 
 extern int posix_memalign(void **memptr, size_t alignment, size_t size);
 
-extern double atof(const char*);
+_BIONIC_NOT_BEFORE_21(extern double atof(const char*);)
 
 extern double strtod(const char*, char**) __LIBC_ABI_PUBLIC__;
-extern float strtof(const char*, char**) __LIBC_ABI_PUBLIC__;
+_BIONIC_NOT_BEFORE_21(extern float strtof(const char*, char**) __LIBC_ABI_PUBLIC__;)
 extern long double strtold(const char*, char**) __LIBC_ABI_PUBLIC__;
 
 extern long double strtold_l(const char *, char **, locale_t) __LIBC_ABI_PUBLIC__;
@@ -90,9 +90,9 @@
 extern long atol(const char*) __purefunc;
 extern long long atoll(const char*) __purefunc;
 
-extern int abs(int) __pure2;
-extern long labs(long) __pure2;
-extern long long llabs(long long) __pure2;
+_BIONIC_NOT_BEFORE_21(extern int abs(int) __pure2;)
+_BIONIC_NOT_BEFORE_21(extern long labs(long) __pure2;)
+_BIONIC_NOT_BEFORE_21(extern long long llabs(long long) __pure2;)
 
 extern char * realpath(const char *path, char *resolved);
 extern int system(const char * string);
@@ -109,9 +109,9 @@
 
 #define RAND_MAX 0x7fffffff
 
-int rand(void);
+_BIONIC_NOT_BEFORE_21(int rand(void);)
 int rand_r(unsigned int*);
-void srand(unsigned int);
+_BIONIC_NOT_BEFORE_21(void srand(unsigned int);)
 
 double drand48(void);
 double erand48(unsigned short[3]);
@@ -124,12 +124,12 @@
 void srand48(long);
 
 char* initstate(unsigned int, char*, size_t);
-long random(void);
+_BIONIC_NOT_BEFORE_21(long random(void);)
 char* setstate(char*);
-void srandom(unsigned int);
+_BIONIC_NOT_BEFORE_21(void srandom(unsigned int);)
 
 int getpt(void);
-int grantpt(int);
+_BIONIC_NOT_BEFORE_21(int grantpt(int);)
 int posix_openpt(int);
 char* ptsname(int);
 int ptsname_r(int, char*, size_t);
@@ -172,6 +172,10 @@
 extern size_t __ctype_get_mb_cur_max(void);
 #define MB_CUR_MAX __ctype_get_mb_cur_max()
 
+#if __ANDROID_API__ < 21
+#include <android/legacy_stdlib_inlines.h>
+#endif
+
 __END_DECLS
 
 #endif /* _STDLIB_H */
diff --git a/libc/include/sys/atomics.h b/libc/include/sys/atomics.h
new file mode 100644
index 0000000..38ab366
--- /dev/null
+++ b/libc/include/sys/atomics.h
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _SYS_ATOMICS_H_
+#define _SYS_ATOMICS_H_
+
+/*
+ * These got proper out of line definitions in L. Putting the inline definitions
+ * back for old targets brings us closer to being able to use one set of headers
+ * for all API levels.
+ *
+ * The other inlines we put back went in to their appropriate headers, but the
+ * sys/atomics.h header was removed, so we'll just add these somewhere we can be
+ * sure they will be included.
+ */
+#if __ANDROID_API__ < 21
+#include <android/legacy_sys_atomics_inlines.h>
+#endif
+
+#endif /* _SYS_ATOMICS_H_ */
diff --git a/libc/include/sys/cdefs.h b/libc/include/sys/cdefs.h
index 21d59fa..48763d7 100644
--- a/libc/include/sys/cdefs.h
+++ b/libc/include/sys/cdefs.h
@@ -556,4 +556,10 @@
 /* Used to rename functions so that the compiler emits a call to 'x' rather than the function this was applied to. */
 #define __RENAME(x) __asm__(#x)
 
+#if __ANDROID_API__ >= 21
+#define _BIONIC_NOT_BEFORE_21(x) x
+#else
+#define _BIONIC_NOT_BEFORE_21(x)
+#endif /* __ANDROID_API__ >= 21 */
+
 #endif /* !_SYS_CDEFS_H_ */
diff --git a/libc/include/sys/stat.h b/libc/include/sys/stat.h
index 7017865..620f46a 100644
--- a/libc/include/sys/stat.h
+++ b/libc/include/sys/stat.h
@@ -171,7 +171,7 @@
 }
 #endif /* defined(__BIONIC_FORTIFY) */
 
-extern int mkfifo(const char*, mode_t);
+_BIONIC_NOT_BEFORE_21(extern int mkfifo(const char*, mode_t);)
 extern int mkfifoat(int, const char*, mode_t);
 
 extern int fchmodat(int, const char*, mode_t, int);
@@ -183,6 +183,10 @@
 extern int utimensat(int fd, const char *path, const struct timespec times[2], int flags);
 extern int futimens(int fd, const struct timespec times[2]);
 
+#if __ANDROID_API__ < 21
+#include <android/legacy_sys_stat_inlines.h>
+#endif
+
 __END_DECLS
 
 #endif /* _SYS_STAT_H_ */
diff --git a/libc/include/termios.h b/libc/include/termios.h
index b9685ca..683fde2 100644
--- a/libc/include/termios.h
+++ b/libc/include/termios.h
@@ -35,6 +35,7 @@
 
 __BEGIN_DECLS
 
+#if __ANDROID_API__ >= 21
 speed_t cfgetispeed(const struct termios*);
 speed_t cfgetospeed(const struct termios*);
 void cfmakeraw(struct termios*);
@@ -48,6 +49,9 @@
 pid_t tcgetsid(int);
 int tcsendbreak(int, int);
 int tcsetattr(int, int, const struct termios*);
+#else
+#include <android/legacy_termios_inlines.h>
+#endif
 
 __END_DECLS