diff --git a/docs/status.md b/docs/status.md
index d589721..e41baa6 100644
--- a/docs/status.md
+++ b/docs/status.md
@@ -37,11 +37,11 @@
 
 Current libc symbols: https://android.googlesource.com/platform/bionic/+/master/libc/libc.map.txt
 
-New libc functions in Q:
+New libc functions in Q (API level 29):
   * `timespec_get` (C11 `<time.h>` addition)
   * `res_randomid` (in `<resolv.h>`)
 
-New libc functions in P:
+New libc functions in P (API level 28):
   * `__freading`/`__fwriting` (completing <stdio_ext.h>)
   * `endhostent`/`endnetent`/`endprotoent`/`getnetent`/`getprotoent`/`sethostent`/`setnetent`/`setprotoent` (completing <netdb.h>)
   * `fexecve`
@@ -58,12 +58,12 @@
   * `swab`
   * `syncfs`
 
-New libc behavior in P:
+New libc behavior in P (API level 28):
   * `%C` and `%S` support in the printf family (previously only the wprintf family supported these)
   * `%mc`/`%ms`/`%m[` support in the scanf family
   * `%s` support in strptime (strftime already supported it)
 
-New libc functions in O:
+New libc functions in O (API level 26):
   * `sendto` FORTIFY support
   * `__system_property_read_callback`/`__system_property_wait`
   * legacy `bsd_signal`
@@ -86,18 +86,90 @@
   * `strtod_l`/`strtof_l`/`strtol_l`/`strtoul_l`
   * <wctype.h> `towctrans`/`towctrans_l`/`wctrans`/`wctrans_l`
 
-New libc functions in N:
+New libc functions in N (API level 24):
   * more FORTIFY support functions (`fread`/`fwrite`/`getcwd`/`pwrite`/`write`)
   * all remaining `_FILE_OFFSET_BITS=64` functions, completing `_FILE_OFFSET_BITS=64` support in bionic (8)
   * all 7 `pthread_barrier*` functions
   * all 5 `pthread_spin*` functions
   * `lockf`/`preadv`/`pwritev`/`scandirat` and `off64_t` variants
   * `adjtimex`/`clock_adjtime`
-  * `getifaddrs`/`freeifaddrs`/`if_freenameindex`/`if_nameindex`
+  * <ifaddrs.h> `getifaddrs`/`freeifaddrs`/`if_freenameindex`/`if_nameindex`
   * `getgrgid_r`/`getgrnam_r`
   * GNU extensions `fileno_unlocked`/`strchrnul`
   * 32-bit `prlimit`
 
+New libc functions in M (API level 23):
+  * <dirent.h> `telldir`, `seekdir`.
+  * <malloc.h> `malloc_info`.
+  * <netdb.h> `gethostbyaddr_r`, `gethostbyname2_r`.
+  * <pthread.h> `pthread_rwlockattr_getkind_np`/`pthread_rwlockattr_setkind_np`.
+  * <pty.h> `forkpty`, `openpty`.
+  * <signal.h> `sigqueue`, `sigtimedwait`, `sigwaitinfo`.
+  * <stdio.h> `fmemopen`, `open_memstream`, `feof_unlocked`, `ferror_unlocked`, `clearerr_unlocked`.
+  * <stdio_ext.h> `__flbf`, `__freadable`, `__fsetlocking`, `__fwritable`, `__fbufsize`, `__fpending`, `_flushlbf`, `__fpurge`.
+  * <stdlib.h> `mkostemp`/`mkostemps`, `lcong48`.
+  * <string.h> `basename`, `strerror_l`, `strerror_r`, `mempcpy`.
+  * <sys/sysinfo.h> `get_nprocs_conf`/`get_nprocs`, `get_phys_pages`, `get_avphys_pages`.
+  * <sys/uio.h> `process_vm_readv`/`process_vm_writev`.
+  * `clock_getcpuclockid`, `login_tty`, `mkfifoat`, `posix_madvise`, `sethostname`, `strcasecmp_l`/`strncasecmp_l`.
+  * <wchar.h> `open_wmemstream`, `wcscasecmp_l`/`wcsncasecmp_l`, `wmempcpy`.
+  * all of <error.h>.
+  * re-introduced various <resolv.h> functions: `ns_format_ttl`, `ns_get16`, `ns_get32`, `ns_initparse`, `ns_makecanon`, `ns_msg_getflag`, `ns_name_compress`, `ns_name_ntol`, `ns_name_ntop`, `ns_name_pack`, `ns_name_pton`, `ns_name_rollback`, `ns_name_skip`, `ns_name_uncompress`, `ns_name_unpack`, `ns_parserr`, `ns_put16`, `ns_put32`, `ns_samename`, `ns_skiprr`, `ns_sprintrr`, and `ns_sprintrrf`.
+
+New libc functions in L (API level 21):
+  * <android/dlext.h>.
+  * <android/set_abort_message.h>.
+  * <arpa/inet.h> `inet_lnaof`, `inet_netof`, `inet_network`, `inet_makeaddr`.
+  * <wctype.h> `iswblank`.
+  * <ctype.h> `isalnum_l`, `isalpha_l`, `isblank_l`, `icntrl_l`, `isdigit_l`, `isgraph_l`, `islower_l`, `isprint_l`, `ispunct_l`, `isspace_l`, `isupper_l`, `isxdigit_l`, `_tolower`, `tolower_l`, `_toupper`, `toupper_l`.
+  * <fcntl.h> `fallocate`, `posix_fadvise`, `posix_fallocate`, `splice`, `tee`, `vmsplice`.
+  * <inttypes.h> `wcstoimax`, `wcstoumax`.
+  * <link.h> `dl_iterate_phdr`.
+  * <mntent.h> `setmntent`, `endmntent`, `getmntent_r`.
+  * <poll.h> `ppoll`.
+  * <pthread.h> `pthread_condattr_getclock`, `pthread_condattr_setclock`, `pthread_mutex_timedlock`, `pthread_gettid_np`.
+  * <sched.h> `setns`.
+  * <search.h> `insque`, `remque`, `lfind`, `lsearch`, `twalk`.
+  * <stdio.h> `dprintf`, `vdprintf`.
+  * <stdlib.h> `initstate`, `setstate`, `getprogname`/`setprogname`, `atof`/`strtof`, `at_quick_exit`/`_Exit`/`quick_exit`, `grantpt`, `mbtowc`/`wctomb`, `posix_openpt`, `rand_r`/`rand`/`random`/`srand`/`srandom`, `strtold_l`/`strtoll_l`/`strtoull_l`.
+  * <string.h> `strcoll_l`/`strxfrm_l`, `stpcpy`/`stpncpy`.
+  * <sys/resource.h> `prlimit`.
+  * <sys/socket.h> `accept4`, `sendmmsg`.
+  * <sys/stat.h> `mkfifo`/`mknodat`.
+  * <time.h> `strftime_l`.
+  * <unistd.h> `dup3`, `execvpe`, `getpagesize`, `linkat`/`symlinkat`/`readlinkat`, `truncate`.
+  * <wchar.h> `wcstof`, `vfwscanf`/`vswscanf`/`vwscanf`, `wcstold_l`/`wcstoll`/`wcstoll_l`/`wcstoull`/`wcstoull_l`, `mbsnrtowcs`/`wcsnrtombs`, `wcscoll_l`/`wcsxfrm_l`.
+  * <wctype.h> `iswalnum_l`/`iswalpha_l`/`iswblank_l`/`iswcntrl_l`/`iswctype_l`/`iswdigit_l`/`iswgraph_l`/`iswlower_l`/`iswprint_l`/`iswpunct_l`/`iswspace_l`/`iswupper_l`/`iswxdigit_l`, `wctype_l`, `towlower_l`/`towupper_l`.
+  * all of <fts.h>.
+  * all of <locale.h>.
+  * all of <sys/epoll.h>.
+  * all of <sys/fsuid.h>.
+  * all of <sys/inotify.h>.
+  * all of <uchar.h>.
+
+New libc functions in K (API level 19):
+  * <inttypes.h> `imaxabs`, `imaxdiv`.
+  * <stdlib.h> `abs`, `labs`, `llabs`.
+  * <sys/stat.h> `futimens`.
+  * all of <sys/statvfs.h>.
+  * all of <sys/swap.h>.
+  * all of <sys/timerfd.h>.
+
+New libc functions in J-MR2 (API level 18):
+  * <stdio.h> `getdelim` and `getline`.
+  * <sys/auxv.h> `getauxval`.
+  * <sys/signalfd.h> `signalfd`.
+
+New libc functions in J-MR1 (API level 17):
+  * <ftw.h>.
+  * <signal.h> `psiginfo` and `psignal`.
+  * `getsid`, `malloc_usable_size`, `mlockall`/`munlockall`, `posix_memalign`, `unshare`.
+
+New libc functions in J (API level 16):
+  * the <search.h> tree functions `tdelete`, `tdestroy`, `tfind`, and `tsearch`.
+  * `faccessat`, `readahead`, `tgkill`.
+  * all of <sys/xattr.h>.
+
 libc function count over time:
   G 803, H 825, I 826, J 846, J-MR1 873, J-MR2 881, K 896, L 1116, M 1181, N 1226, O 1278
 
@@ -112,7 +184,19 @@
 
 0 remaining missing POSIX libm functions.
 
-19 new libm functions in O: complex trig/exp/log functions.
+New libm functions in O (API level 26):
+  * <complex.h> `clog`/`clogf`, `cpow`/`cpowf` functions.
+
+New libm functions in M (API level 23):
+  * <complex.h> `cabs`, `carg`, `cimag`, `cacos`, `cacosh`, `casin`, `casinh`, `catan`, `catanh`, `ccos`, `ccosh`, `cexp`, `conj`, `cproj`, `csin`, `csinh`, `csqrt`, `ctan`, `ctanh`, `creal`, `cabsf`, `cargf`, `cimagf`, `cacosf`, `cacoshf`, `casinf`, `casinhf`, `catanf`, `catanhf`, `ccosf`, `ccoshf`, `cexpf`, `conjf`, `cprojf`, `csinf`, `csinhf`, `csqrtf`, `ctanf`, `ctanhf`, `crealf`, `cabsl`, `cprojl`, `csqrtl`.
+  * <math.h> `lgammal_r`.
+
+New libm functions in L (API level 21):
+  * <complex.h> `cabsl`, `cprojl`, `csqrtl`.
+  * <math.h> `isinf`, `significandl`.
+
+New libm functions in J-MR2 (API level 18):
+  * <math.h> `log2`, `log2f`.
 
 libm function count over time:
   G 158, J-MR2 164, L 220, M 265, O 284
diff --git a/libc/arch-arm64/generic/bionic/__memcpy_chk.S b/libc/arch-arm64/generic/bionic/__memcpy_chk.S
index 4217775..a6eeca4 100644
--- a/libc/arch-arm64/generic/bionic/__memcpy_chk.S
+++ b/libc/arch-arm64/generic/bionic/__memcpy_chk.S
@@ -30,8 +30,11 @@
 
 ENTRY(__memcpy_chk)
   cmp x2, x3
-  bls memcpy
+  // Direct b.ls memcpy may not have enough range
+  b.hi .L_memcpy_chk_fail
+  b memcpy
 
+.L_memcpy_chk_fail:
   // Preserve for accurate backtrace.
   stp x29, x30, [sp, -16]!
   .cfi_def_cfa_offset 16
diff --git a/libc/bionic/abort.cpp b/libc/bionic/abort.cpp
index d2c99a5..c8bba01 100644
--- a/libc/bionic/abort.cpp
+++ b/libc/bionic/abort.cpp
@@ -32,32 +32,9 @@
 #include <sys/syscall.h>
 #include <unistd.h>
 
-// We call tgkill(2) directly instead of raise (or even the libc tgkill wrapper), to reduce the
-// number of uninteresting stack frames at the top of a crash.
-static inline __always_inline void inline_tgkill(pid_t pid, pid_t tid, int sig) {
-#if defined(__arm__)
-  register int r0 __asm__("r0") = pid;
-  register int r1 __asm__("r1") = tid;
-  register int r2 __asm__("r2") = sig;
-  register int r7 __asm__("r7") = __NR_tgkill;
-  __asm__("swi #0" : "=r"(r0) : "r"(r0), "r"(r1), "r"(r2), "r"(r7) : "memory");
-#elif defined(__aarch64__)
-  register long x0 __asm__("x0") = pid;
-  register long x1 __asm__("x1") = tid;
-  register long x2 __asm__("x2") = sig;
-  register long x8 __asm__("x8") = __NR_tgkill;
-  __asm__("svc #0" : "=r"(x0) : "r"(x0), "r"(x1), "r"(x2), "r"(x8) : "memory");
-#else
-  syscall(__NR_tgkill, pid, tid, sig);
-#endif
-}
+#include "private/bionic_inline_raise.h"
 
 void abort() {
-  // Protect ourselves against stale cached PID/TID values by fetching them via syscall.
-  // http://b/37769298
-  pid_t pid = syscall(__NR_getpid);
-  pid_t tid = syscall(__NR_gettid);
-
   // Don't block SIGABRT to give any signal handler a chance; we ignore
   // any errors -- X311J doesn't allow abort to return anyway.
   sigset64_t mask;
@@ -65,7 +42,7 @@
   sigdelset64(&mask, SIGABRT);
 
   sigprocmask64(SIG_SETMASK, &mask, nullptr);
-  inline_tgkill(pid, tid, SIGABRT);
+  inline_raise(SIGABRT);
 
   // If SIGABRT is ignored or it's caught and the handler returns,
   // remove the SIGABRT signal handler and raise SIGABRT again.
@@ -73,7 +50,7 @@
   sigaction64(SIGABRT, &sa, nullptr);
 
   sigprocmask64(SIG_SETMASK, &mask, nullptr);
-  inline_tgkill(pid, tid, SIGABRT);
+  inline_raise(SIGABRT);
 
   // If we get this far, just exit.
   _exit(127);
diff --git a/libc/bionic/fdsan.cpp b/libc/bionic/fdsan.cpp
index ad1ddee..31ffa96 100644
--- a/libc/bionic/fdsan.cpp
+++ b/libc/bionic/fdsan.cpp
@@ -43,6 +43,7 @@
 #include <sys/system_properties.h>
 
 #include "private/bionic_globals.h"
+#include "private/bionic_inline_raise.h"
 #include "pthread_internal.h"
 
 extern "C" int ___close(int fd);
@@ -200,12 +201,11 @@
       __BIONIC_FALLTHROUGH;
     case ANDROID_FDSAN_ERROR_LEVEL_WARN_ALWAYS:
       // DEBUGGER_SIGNAL
-      sigval abort_msg;
-      abort_msg.sival_ptr = &abort_message;
-      pthread_sigqueue(pthread_self(), __SIGRTMIN + 3, abort_msg);
+      inline_raise(__SIGRTMIN + 3, &abort_message);
       break;
 
     case ANDROID_FDSAN_ERROR_LEVEL_FATAL:
+      inline_raise(SIGABRT);
       abort();
 
     case ANDROID_FDSAN_ERROR_LEVEL_DISABLED:
@@ -247,6 +247,8 @@
       return "ParcelFileDescriptor";
     case ANDROID_FDSAN_OWNER_TYPE_SQLITE:
       return "sqlite";
+    case ANDROID_FDSAN_OWNER_TYPE_ART_FDFILE:
+      return "ART FdFile";
 
     case ANDROID_FDSAN_OWNER_TYPE_GENERIC_00:
     default:
diff --git a/libc/include/android/fdsan.h b/libc/include/android/fdsan.h
index cbea460..dc2bbd5 100644
--- a/libc/include/android/fdsan.h
+++ b/libc/include/android/fdsan.h
@@ -111,6 +111,9 @@
 
   /* android.os.ParcelFileDescriptor */
   ANDROID_FDSAN_OWNER_TYPE_PARCELFILEDESCRIPTOR = 8,
+
+  /* ART FdFile */
+  ANDROID_FDSAN_OWNER_TYPE_ART_FDFILE = 9,
 };
 
 /*
diff --git a/libc/include/android/legacy_fenv_inlines_arm.h b/libc/include/android/legacy_fenv_inlines_arm.h
index 6f2c959..5ec5582 100644
--- a/libc/include/android/legacy_fenv_inlines_arm.h
+++ b/libc/include/android/legacy_fenv_inlines_arm.h
@@ -1,141 +1,43 @@
-/*-
- * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
+/*
+ * Copyright (C) 2018 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:
- * 1. Redistributions of source code must retain the above copyright
+ *  * Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
- * 2. 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.
+ *  * 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 AUTHOR 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 AUTHOR 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
+ * 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.
- *
- * $FreeBSD: src/lib/msun/arm/fenv.c,v 1.1 2004/06/06 10:03:59 das Exp $
  */
 
-#ifndef ANDROID_LEGACY_FENV_INLINES_ARM_H
-#define ANDROID_LEGACY_FENV_INLINES_ARM_H
+#pragma once
+
+/**
+ * @file legacy_fenv_inlines_arm.h
+ * @brief Inline ARM-specific definitions of fenv for old API levels.
+ */
 
 #include <sys/cdefs.h>
 
 #if __ANDROID_API__ < __ANDROID_API_L__ && defined(__arm__)
 
-#include <fenv.h>
+#define __BIONIC_FENV_INLINE static __inline
+#include <bits/fenv_inlines_arm.h>
 
-__BEGIN_DECLS
-
-#define FPSCR_RMODE_SHIFT 22
-
-static __inline int fegetenv(fenv_t* __envp) {
-  fenv_t _fpscr;
-  __asm__ __volatile__("vmrs %0,fpscr" : "=r" (_fpscr));
-  *__envp = _fpscr;
-  return 0;
-}
-
-static __inline int fesetenv(const fenv_t* __envp) {
-  fenv_t _fpscr = *__envp;
-  __asm__ __volatile__("vmsr fpscr,%0" : :"ri" (_fpscr));
-  return 0;
-}
-
-static __inline int feclearexcept(int __excepts) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  __fpscr &= ~__excepts;
-  fesetenv(&__fpscr);
-  return 0;
-}
-
-static __inline int fegetexceptflag(fexcept_t* __flagp, int __excepts) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  *__flagp = __fpscr & __excepts;
-  return 0;
-}
-
-static __inline int fesetexceptflag(const fexcept_t* __flagp, int __excepts) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  __fpscr &= ~__excepts;
-  __fpscr |= *__flagp & __excepts;
-  fesetenv(&__fpscr);
-  return 0;
-}
-
-static __inline int feraiseexcept(int __excepts) {
-  fexcept_t __ex = __excepts;
-  fesetexceptflag(&__ex, __excepts);
-  return 0;
-}
-
-static __inline int fetestexcept(int __excepts) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  return (__fpscr & __excepts);
-}
-
-static __inline int fegetround(void) {
-  fenv_t _fpscr;
-  fegetenv(&_fpscr);
-  return ((_fpscr >> FPSCR_RMODE_SHIFT) & 0x3);
-}
-
-static __inline int fesetround(int __round) {
-  fenv_t _fpscr;
-  fegetenv(&_fpscr);
-  _fpscr &= ~(0x3 << FPSCR_RMODE_SHIFT);
-  _fpscr |= (__round << FPSCR_RMODE_SHIFT);
-  fesetenv(&_fpscr);
-  return 0;
-}
-
-static __inline int feholdexcept(fenv_t* __envp) {
-  fenv_t __env;
-  fegetenv(&__env);
-  *__envp = __env;
-  __env &= ~FE_ALL_EXCEPT;
-  fesetenv(&__env);
-  return 0;
-}
-
-static __inline int feupdateenv(const fenv_t* __envp) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  fesetenv(__envp);
-  feraiseexcept(__fpscr & FE_ALL_EXCEPT);
-  return 0;
-}
-
-static __inline int feenableexcept(int __mask __unused) {
-  return -1;
-}
-
-static __inline int fedisableexcept(int __mask __unused) {
-  return 0;
-}
-
-static __inline int fegetexcept(void) {
-  return 0;
-}
-
-#undef FPSCR_RMODE_SHIFT
-
-__END_DECLS
-
-#endif /* __ANDROID_API__ < __ANDROID_API_L__ && defined(__arm__) */
-
-#endif /* ANDROID_LEGACY_FENV_INLINES_ARM_H */
+#endif
diff --git a/libc/include/android/legacy_fenv_inlines_mips.h b/libc/include/android/legacy_fenv_inlines_mips.h
index 43ad360..ccc824c 100644
--- a/libc/include/android/legacy_fenv_inlines_mips.h
+++ b/libc/include/android/legacy_fenv_inlines_mips.h
@@ -1,170 +1,43 @@
-/*-
- * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
+/*
+ * Copyright (C) 2018 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:
- * 1. Redistributions of source code must retain the above copyright
+ *  * Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
- * 2. 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.
+ *  * 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 AUTHOR 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 AUTHOR 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
+ * 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.
- *
- * $FreeBSD: src/lib/msun/mips/fenv.c,v 1.1 2008/04/26 12:20:29 imp Exp $
  */
 
-#ifndef ANDROID_LEGACY_FENV_INLINES_MIPS_H
-#define ANDROID_LEGACY_FENV_INLINES_MIPS_H
+#pragma once
+
+/**
+ * @file legacy_fenv_inlines_mips.h
+ * @brief Inline MIPS-specific definitions of fenv for old API levels.
+ */
 
 #include <sys/cdefs.h>
 
 #if __ANDROID_API__ < __ANDROID_API_L__ && (defined(__mips__) && !defined(__LP64__))
 
-#include <fenv.h>
+#define __BIONIC_FENV_INLINE static __inline
+#include <bits/fenv_inlines_mips.h>
 
-__BEGIN_DECLS
-
-#define FCSR_CAUSE_SHIFT 10
-#define FCSR_ENABLE_SHIFT 5
-#define FCSR_ENABLE_MASK (FE_ALL_EXCEPT << FCSR_ENABLE_SHIFT)
-
-#define FCSR_RMASK       0x3
-
-static __inline int fegetenv(fenv_t* __envp) {
-  fenv_t _fcsr = 0;
-#ifdef  __mips_hard_float
-  __asm__ __volatile__("cfc1 %0,$31" : "=r" (_fcsr));
 #endif
-  *__envp = _fcsr;
-  return 0;
-}
-
-static __inline int fesetenv(const fenv_t* __envp) {
-  fenv_t _fcsr = *__envp;
-#ifdef  __mips_hard_float
-  __asm__ __volatile__("ctc1 %0,$31" : : "r" (_fcsr));
-#endif
-  return 0;
-}
-
-static __inline int feclearexcept(int __excepts) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  __excepts &= FE_ALL_EXCEPT;
-  __fcsr &= ~(__excepts | (__excepts << FCSR_CAUSE_SHIFT));
-  fesetenv(&__fcsr);
-  return 0;
-}
-
-static __inline int fegetexceptflag(fexcept_t* __flagp, int __excepts) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  *__flagp = __fcsr & __excepts & FE_ALL_EXCEPT;
-  return 0;
-}
-
-static __inline int fesetexceptflag(const fexcept_t* __flagp, int __excepts) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  /* Ensure that flags are all legal */
-  __excepts &= FE_ALL_EXCEPT;
-  __fcsr &= ~__excepts;
-  __fcsr |= *__flagp & __excepts;
-  fesetenv(&__fcsr);
-  return 0;
-}
-
-static __inline int feraiseexcept(int __excepts) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  /* Ensure that flags are all legal */
-  __excepts &= FE_ALL_EXCEPT;
-  /* Cause bit needs to be set as well for generating the exception*/
-  __fcsr |= __excepts | (__excepts << FCSR_CAUSE_SHIFT);
-  fesetenv(&__fcsr);
-  return 0;
-}
-
-static __inline int fetestexcept(int __excepts) {
-  fexcept_t __FCSR;
-  fegetenv(&__FCSR);
-  return (__FCSR & __excepts & FE_ALL_EXCEPT);
-}
-
-static __inline int fegetround(void) {
-  fenv_t _fcsr;
-  fegetenv(&_fcsr);
-  return (_fcsr & FCSR_RMASK);
-}
-
-static __inline int fesetround(int __round) {
-  fenv_t _fcsr;
-  fegetenv(&_fcsr);
-  _fcsr &= ~FCSR_RMASK;
-  _fcsr |= (__round & FCSR_RMASK);
-  fesetenv(&_fcsr);
-  return 0;
-}
-
-static __inline int feholdexcept(fenv_t* __envp) {
-  fenv_t __env;
-  fegetenv(&__env);
-  *__envp = __env;
-  __env &= ~(FE_ALL_EXCEPT | FCSR_ENABLE_MASK);
-  fesetenv(&__env);
-  return 0;
-}
-
-static __inline int feupdateenv(const fenv_t* __envp) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  fesetenv(__envp);
-  feraiseexcept(__fcsr & FE_ALL_EXCEPT);
-  return 0;
-}
-
-static __inline int feenableexcept(int __mask) {
-  fenv_t __old_fcsr, __new_fcsr;
-  fegetenv(&__old_fcsr);
-  __new_fcsr = __old_fcsr | (__mask & FE_ALL_EXCEPT) << FCSR_ENABLE_SHIFT;
-  fesetenv(&__new_fcsr);
-  return ((__old_fcsr >> FCSR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
-}
-
-static __inline int fedisableexcept(int __mask) {
-  fenv_t __old_fcsr, __new_fcsr;
-  fegetenv(&__old_fcsr);
-  __new_fcsr = __old_fcsr & ~((__mask & FE_ALL_EXCEPT) << FCSR_ENABLE_SHIFT);
-  fesetenv(&__new_fcsr);
-  return ((__old_fcsr >> FCSR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
-}
-
-static __inline int fegetexcept(void) {
-  fenv_t __fcsr;
-  fegetenv(&__fcsr);
-  return ((__fcsr & FCSR_ENABLE_MASK) >> FCSR_ENABLE_SHIFT);
-}
-
-#undef FCSR_CAUSE_SHIFT
-#undef FCSR_ENABLE_SHIFT
-#undef FCSR_ENABLE_MASK
-#undef FCSR_RMASK
-
-__END_DECLS
-
-#endif /* __ANDROID_API__ < __ANDROID_API_L__ && (defined(__mips__) && !defined(__LP64__)) */
-
-#endif /* ANDROID_LEGACY_FENV_INLINES_MIPS_H */
diff --git a/libc/include/bits/fenv_arm.h b/libc/include/bits/fenv_arm.h
index 042fec3..0cd4844 100644
--- a/libc/include/bits/fenv_arm.h
+++ b/libc/include/bits/fenv_arm.h
@@ -26,8 +26,7 @@
  * $FreeBSD: src/lib/msun/arm/fenv.h,v 1.5 2005/03/16 19:03:45 das Exp $
  */
 
-#ifndef _BITS_FENV_ARM_H_
-#define _BITS_FENV_ARM_H_
+#pragma once
 
 #include <sys/types.h>
 
@@ -73,5 +72,3 @@
 #define FE_TOWARDZERO 0x3
 
 __END_DECLS
-
-#endif
diff --git a/libc/include/bits/fenv_inlines_arm.h b/libc/include/bits/fenv_inlines_arm.h
new file mode 100644
index 0000000..e8b89ea
--- /dev/null
+++ b/libc/include/bits/fenv_inlines_arm.h
@@ -0,0 +1,142 @@
+/*-
+ * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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 AUTHOR 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 AUTHOR 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.
+ *
+ * $FreeBSD: src/lib/msun/arm/fenv.c,v 1.1 2004/06/06 10:03:59 das Exp $
+ */
+
+#pragma once
+
+#include <sys/cdefs.h>
+
+#if defined(__arm__)
+
+#if !defined(__BIONIC_FENV_INLINE)
+#define __BIONIC_FENV_INLINE static __inline
+#endif
+
+#include <bits/fenv_arm.h>
+
+__BEGIN_DECLS
+
+#define FPSCR_RMODE_SHIFT 22
+
+__BIONIC_FENV_INLINE int fegetenv(fenv_t* __envp) {
+  fenv_t _fpscr;
+  __asm__ __volatile__("vmrs %0,fpscr" : "=r" (_fpscr));
+  *__envp = _fpscr;
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int fesetenv(const fenv_t* __envp) {
+  fenv_t _fpscr = *__envp;
+  __asm__ __volatile__("vmsr fpscr,%0" : :"ri" (_fpscr));
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feclearexcept(int __excepts) {
+  fexcept_t __fpscr;
+  fegetenv(&__fpscr);
+  __fpscr &= ~__excepts;
+  fesetenv(&__fpscr);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int fegetexceptflag(fexcept_t* __flagp, int __excepts) {
+  fexcept_t __fpscr;
+  fegetenv(&__fpscr);
+  *__flagp = __fpscr & __excepts;
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int fesetexceptflag(const fexcept_t* __flagp, int __excepts) {
+  fexcept_t __fpscr;
+  fegetenv(&__fpscr);
+  __fpscr &= ~__excepts;
+  __fpscr |= *__flagp & __excepts;
+  fesetenv(&__fpscr);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feraiseexcept(int __excepts) {
+  fexcept_t __ex = __excepts;
+  fesetexceptflag(&__ex, __excepts);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int fetestexcept(int __excepts) {
+  fexcept_t __fpscr;
+  fegetenv(&__fpscr);
+  return (__fpscr & __excepts);
+}
+
+__BIONIC_FENV_INLINE int fegetround(void) {
+  fenv_t _fpscr;
+  fegetenv(&_fpscr);
+  return ((_fpscr >> FPSCR_RMODE_SHIFT) & 0x3);
+}
+
+__BIONIC_FENV_INLINE int fesetround(int __round) {
+  fenv_t _fpscr;
+  fegetenv(&_fpscr);
+  _fpscr &= ~(0x3 << FPSCR_RMODE_SHIFT);
+  _fpscr |= (__round << FPSCR_RMODE_SHIFT);
+  fesetenv(&_fpscr);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feholdexcept(fenv_t* __envp) {
+  fenv_t __env;
+  fegetenv(&__env);
+  *__envp = __env;
+  __env &= ~FE_ALL_EXCEPT;
+  fesetenv(&__env);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feupdateenv(const fenv_t* __envp) {
+  fexcept_t __fpscr;
+  fegetenv(&__fpscr);
+  fesetenv(__envp);
+  feraiseexcept(__fpscr & FE_ALL_EXCEPT);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feenableexcept(int __mask __unused) {
+  return -1;
+}
+
+__BIONIC_FENV_INLINE int fedisableexcept(int __mask __unused) {
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int fegetexcept(void) {
+  return 0;
+}
+
+#undef FPSCR_RMODE_SHIFT
+
+__END_DECLS
+
+#endif
diff --git a/libc/include/bits/fenv_inlines_mips.h b/libc/include/bits/fenv_inlines_mips.h
new file mode 100644
index 0000000..dc7f707
--- /dev/null
+++ b/libc/include/bits/fenv_inlines_mips.h
@@ -0,0 +1,171 @@
+/*-
+ * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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 AUTHOR 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 AUTHOR 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.
+ *
+ * $FreeBSD: src/lib/msun/mips/fenv.c,v 1.1 2008/04/26 12:20:29 imp Exp $
+ */
+
+#pragma once
+
+#include <sys/cdefs.h>
+
+#if defined(__mips__)
+
+#if !defined(__BIONIC_FENV_INLINE)
+#define __BIONIC_FENV_INLINE static __inline
+#endif
+
+#include <bits/fenv_mips.h>
+
+__BEGIN_DECLS
+
+#define FCSR_CAUSE_SHIFT 10
+#define FCSR_ENABLE_SHIFT 5
+#define FCSR_ENABLE_MASK (FE_ALL_EXCEPT << FCSR_ENABLE_SHIFT)
+
+#define FCSR_RMASK       0x3
+
+__BIONIC_FENV_INLINE int fegetenv(fenv_t* __envp) {
+  fenv_t _fcsr = 0;
+#ifdef  __mips_hard_float
+  __asm__ __volatile__("cfc1 %0,$31" : "=r" (_fcsr));
+#endif
+  *__envp = _fcsr;
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int fesetenv(const fenv_t* __envp) {
+  fenv_t _fcsr = *__envp;
+#ifdef  __mips_hard_float
+  __asm__ __volatile__("ctc1 %0,$31" : : "r" (_fcsr));
+#endif
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feclearexcept(int __excepts) {
+  fexcept_t __fcsr;
+  fegetenv(&__fcsr);
+  __excepts &= FE_ALL_EXCEPT;
+  __fcsr &= ~(__excepts | (__excepts << FCSR_CAUSE_SHIFT));
+  fesetenv(&__fcsr);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int fegetexceptflag(fexcept_t* __flagp, int __excepts) {
+  fexcept_t __fcsr;
+  fegetenv(&__fcsr);
+  *__flagp = __fcsr & __excepts & FE_ALL_EXCEPT;
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int fesetexceptflag(const fexcept_t* __flagp, int __excepts) {
+  fexcept_t __fcsr;
+  fegetenv(&__fcsr);
+  /* Ensure that flags are all legal */
+  __excepts &= FE_ALL_EXCEPT;
+  __fcsr &= ~__excepts;
+  __fcsr |= *__flagp & __excepts;
+  fesetenv(&__fcsr);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feraiseexcept(int __excepts) {
+  fexcept_t __fcsr;
+  fegetenv(&__fcsr);
+  /* Ensure that flags are all legal */
+  __excepts &= FE_ALL_EXCEPT;
+  /* Cause bit needs to be set as well for generating the exception*/
+  __fcsr |= __excepts | (__excepts << FCSR_CAUSE_SHIFT);
+  fesetenv(&__fcsr);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int fetestexcept(int __excepts) {
+  fexcept_t __FCSR;
+  fegetenv(&__FCSR);
+  return (__FCSR & __excepts & FE_ALL_EXCEPT);
+}
+
+__BIONIC_FENV_INLINE int fegetround(void) {
+  fenv_t _fcsr;
+  fegetenv(&_fcsr);
+  return (_fcsr & FCSR_RMASK);
+}
+
+__BIONIC_FENV_INLINE int fesetround(int __round) {
+  fenv_t _fcsr;
+  fegetenv(&_fcsr);
+  _fcsr &= ~FCSR_RMASK;
+  _fcsr |= (__round & FCSR_RMASK);
+  fesetenv(&_fcsr);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feholdexcept(fenv_t* __envp) {
+  fenv_t __env;
+  fegetenv(&__env);
+  *__envp = __env;
+  __env &= ~(FE_ALL_EXCEPT | FCSR_ENABLE_MASK);
+  fesetenv(&__env);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feupdateenv(const fenv_t* __envp) {
+  fexcept_t __fcsr;
+  fegetenv(&__fcsr);
+  fesetenv(__envp);
+  feraiseexcept(__fcsr & FE_ALL_EXCEPT);
+  return 0;
+}
+
+__BIONIC_FENV_INLINE int feenableexcept(int __mask) {
+  fenv_t __old_fcsr, __new_fcsr;
+  fegetenv(&__old_fcsr);
+  __new_fcsr = __old_fcsr | (__mask & FE_ALL_EXCEPT) << FCSR_ENABLE_SHIFT;
+  fesetenv(&__new_fcsr);
+  return ((__old_fcsr >> FCSR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
+}
+
+__BIONIC_FENV_INLINE int fedisableexcept(int __mask) {
+  fenv_t __old_fcsr, __new_fcsr;
+  fegetenv(&__old_fcsr);
+  __new_fcsr = __old_fcsr & ~((__mask & FE_ALL_EXCEPT) << FCSR_ENABLE_SHIFT);
+  fesetenv(&__new_fcsr);
+  return ((__old_fcsr >> FCSR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
+}
+
+__BIONIC_FENV_INLINE int fegetexcept(void) {
+  fenv_t __fcsr;
+  fegetenv(&__fcsr);
+  return ((__fcsr & FCSR_ENABLE_MASK) >> FCSR_ENABLE_SHIFT);
+}
+
+#undef FCSR_CAUSE_SHIFT
+#undef FCSR_ENABLE_SHIFT
+#undef FCSR_ENABLE_MASK
+#undef FCSR_RMASK
+
+__END_DECLS
+
+#endif
diff --git a/libc/include/bits/fenv_mips.h b/libc/include/bits/fenv_mips.h
index 9298e86..dafccac 100644
--- a/libc/include/bits/fenv_mips.h
+++ b/libc/include/bits/fenv_mips.h
@@ -68,8 +68,7 @@
  * 11 - rounding (down)toward minus infinity (RM)
  */
 
-#ifndef _BITS_FENV_MIPS_H_
-#define _BITS_FENV_MIPS_H_
+#pragma once
 
 #include <sys/types.h>
 
@@ -94,5 +93,3 @@
 #define FE_DOWNWARD   0x0003
 
 __END_DECLS
-
-#endif
diff --git a/libc/include/bits/fenv_x86.h b/libc/include/bits/fenv_x86.h
index 75b109b..3381cea 100644
--- a/libc/include/bits/fenv_x86.h
+++ b/libc/include/bits/fenv_x86.h
@@ -26,8 +26,7 @@
  * $FreeBSD: src/lib/msun/i387/fenv.h,v 1.4 2005/03/17 22:21:46 das Exp $
  */
 
-#ifndef _BITS_FENV_X86_H_
-#define _BITS_FENV_X86_H_
+#pragma once
 
 #include <sys/types.h>
 
@@ -65,5 +64,3 @@
 #define FE_TOWARDZERO 0x0c00
 
 __END_DECLS
-
-#endif
diff --git a/libc/include/bits/fenv_x86_64.h b/libc/include/bits/fenv_x86_64.h
index 006d19e..ddb6a5c 100644
--- a/libc/include/bits/fenv_x86_64.h
+++ b/libc/include/bits/fenv_x86_64.h
@@ -24,8 +24,7 @@
  * SUCH DAMAGE.
  */
 
-#ifndef _BITS_FENV_X86_64_H_
-#define _BITS_FENV_X86_64_H_
+#pragma once
 
 #include <sys/types.h>
 
@@ -91,5 +90,3 @@
 typedef __uint32_t fexcept_t;
 
 __END_DECLS
-
-#endif
diff --git a/libc/include/fenv.h b/libc/include/fenv.h
index 2b607f5..886612e 100644
--- a/libc/include/fenv.h
+++ b/libc/include/fenv.h
@@ -27,8 +27,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef _FENV_H_
-#define _FENV_H_
+#pragma once
 
 #include <sys/cdefs.h>
 
@@ -79,11 +78,12 @@
  * environment, namely fesetenv() and feupdateenv().
  */
 extern const fenv_t __fe_dfl_env;
-#define FE_DFL_ENV  (&__fe_dfl_env)
+#define FE_DFL_ENV (&__fe_dfl_env)
 
 __END_DECLS
 
+#if defined(__arm__)
 #include <android/legacy_fenv_inlines_arm.h>
+#elif defined(__mips__)
 #include <android/legacy_fenv_inlines_mips.h>
-
-#endif  /* ! _FENV_H_ */
+#endif
diff --git a/libc/private/bionic_inline_raise.h b/libc/private/bionic_inline_raise.h
new file mode 100644
index 0000000..7223b4e
--- /dev/null
+++ b/libc/private/bionic_inline_raise.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+#pragma once
+
+#include <sys/cdefs.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+// An inline version of pthread_sigqueue(pthread_self(), ...), to reduce the number of
+// uninteresting stack frames at the top of a crash.
+static inline __always_inline void inline_raise(int sig, void* value = nullptr) {
+  // Protect ourselves against stale cached PID/TID values by fetching them via syscall.
+  // http://b/37769298
+  pid_t pid = syscall(__NR_getpid);
+  pid_t tid = syscall(__NR_gettid);
+  siginfo_t info = {};
+  info.si_code = SI_QUEUE;
+  info.si_pid = pid;
+  info.si_uid = getuid();
+  info.si_value.sival_ptr = value;
+
+#if defined(__arm__)
+  register long r0 __asm__("r0") = pid;
+  register long r1 __asm__("r1") = tid;
+  register long r2 __asm__("r2") = sig;
+  register long r3 __asm__("r3") = reinterpret_cast<long>(&info);
+  register long r7 __asm__("r7") = __NR_rt_tgsigqueueinfo;
+  __asm__("swi #0" : "=r"(r0) : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r7) : "memory");
+#elif defined(__aarch64__)
+  register long x0 __asm__("x0") = pid;
+  register long x1 __asm__("x1") = tid;
+  register long x2 __asm__("x2") = sig;
+  register long x3 __asm__("x3") = reinterpret_cast<long>(&info);
+  register long x8 __asm__("x8") = __NR_rt_tgsigqueueinfo;
+  __asm__("svc #0" : "=r"(x0) : "r"(x0), "r"(x1), "r"(x2), "r"(x3), "r"(x8) : "memory");
+#else
+  syscall(__NR_rt_tgsigqueueinfo, pid, tid, sig, &info);
+#endif
+}
+
diff --git a/libm/arm/fenv.c b/libm/arm/fenv.c
index c988e4f..67c6456 100644
--- a/libm/arm/fenv.c
+++ b/libm/arm/fenv.c
@@ -1,126 +1,34 @@
-/*-
- * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
+/*
+ * Copyright (C) 2018 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:
- * 1. Redistributions of source code must retain the above copyright
+ *  * Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
- * 2. 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.
+ *  * 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 AUTHOR 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 AUTHOR 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
+ * 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.
- *
- * $FreeBSD: src/lib/msun/arm/fenv.c,v 1.1 2004/06/06 10:03:59 das Exp $
  */
 
 #include <fenv.h>
 
-#define FPSCR_RMODE_SHIFT 22
+#define __BIONIC_FENV_INLINE /* Out of line. */
+#include <bits/fenv_inlines_arm.h>
 
 const fenv_t __fe_dfl_env = 0;
-
-int fegetenv(fenv_t* __envp) {
-  fenv_t _fpscr;
-  __asm__ __volatile__("vmrs %0,fpscr" : "=r" (_fpscr));
-  *__envp = _fpscr;
-  return 0;
-}
-
-int fesetenv(const fenv_t* __envp) {
-  fenv_t _fpscr = *__envp;
-  __asm__ __volatile__("vmsr fpscr,%0" : :"ri" (_fpscr));
-  return 0;
-}
-
-int feclearexcept(int __excepts) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  __fpscr &= ~__excepts;
-  fesetenv(&__fpscr);
-  return 0;
-}
-
-int fegetexceptflag(fexcept_t* __flagp, int __excepts) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  *__flagp = __fpscr & __excepts;
-  return 0;
-}
-
-int fesetexceptflag(const fexcept_t* __flagp, int __excepts) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  __fpscr &= ~__excepts;
-  __fpscr |= *__flagp & __excepts;
-  fesetenv(&__fpscr);
-  return 0;
-}
-
-int feraiseexcept(int __excepts) {
-  fexcept_t __ex = __excepts;
-  fesetexceptflag(&__ex, __excepts);
-  return 0;
-}
-
-int fetestexcept(int __excepts) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  return (__fpscr & __excepts);
-}
-
-int fegetround(void) {
-  fenv_t _fpscr;
-  fegetenv(&_fpscr);
-  return ((_fpscr >> FPSCR_RMODE_SHIFT) & 0x3);
-}
-
-int fesetround(int __round) {
-  fenv_t _fpscr;
-  fegetenv(&_fpscr);
-  _fpscr &= ~(0x3 << FPSCR_RMODE_SHIFT);
-  _fpscr |= (__round << FPSCR_RMODE_SHIFT);
-  fesetenv(&_fpscr);
-  return 0;
-}
-
-int feholdexcept(fenv_t* __envp) {
-  fenv_t __env;
-  fegetenv(&__env);
-  *__envp = __env;
-  __env &= ~FE_ALL_EXCEPT;
-  fesetenv(&__env);
-  return 0;
-}
-
-int feupdateenv(const fenv_t* __envp) {
-  fexcept_t __fpscr;
-  fegetenv(&__fpscr);
-  fesetenv(__envp);
-  feraiseexcept(__fpscr & FE_ALL_EXCEPT);
-  return 0;
-}
-
-int feenableexcept(int __mask __unused) {
-  return -1;
-}
-
-int fedisableexcept(int __mask __unused) {
-  return 0;
-}
-
-int fegetexcept(void) {
-  return 0;
-}
diff --git a/libm/mips/fenv.c b/libm/mips/fenv.c
index aacd526..f380b74 100644
--- a/libm/mips/fenv.c
+++ b/libm/mips/fenv.c
@@ -1,156 +1,34 @@
-/*-
- * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
+/*
+ * Copyright (C) 2018 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:
- * 1. Redistributions of source code must retain the above copyright
+ *  * Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
- * 2. 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.
+ *  * 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 AUTHOR 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 AUTHOR 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
+ * 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.
- *
- * $FreeBSD: src/lib/msun/mips/fenv.c,v 1.1 2008/04/26 12:20:29 imp Exp $
  */
 
 #include <fenv.h>
 
-#define FCSR_CAUSE_SHIFT 10
-#define FCSR_ENABLE_SHIFT 5
-#define FCSR_ENABLE_MASK (FE_ALL_EXCEPT << FCSR_ENABLE_SHIFT)
+#define __BIONIC_FENV_INLINE /* Out of line. */
+#include <bits/fenv_inlines_mips.h>
 
-#define FCSR_RMASK       0x3
-
-/*
- * Hopefully the system ID byte is immutable, so it's valid to use
- * this as a default environment.
- */
 const fenv_t __fe_dfl_env = 0;
-
-int fegetenv(fenv_t* __envp) {
-  fenv_t _fcsr = 0;
-#ifdef  __mips_hard_float
-  __asm__ __volatile__("cfc1 %0,$31" : "=r" (_fcsr));
-#endif
-  *__envp = _fcsr;
-  return 0;
-}
-
-int fesetenv(const fenv_t* __envp) {
-  fenv_t _fcsr = *__envp;
-#ifdef  __mips_hard_float
-  __asm__ __volatile__("ctc1 %0,$31" : : "r" (_fcsr));
-#endif
-  return 0;
-}
-
-int feclearexcept(int __excepts) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  __excepts &= FE_ALL_EXCEPT;
-  __fcsr &= ~(__excepts | (__excepts << FCSR_CAUSE_SHIFT));
-  fesetenv(&__fcsr);
-  return 0;
-}
-
-int fegetexceptflag(fexcept_t* __flagp, int __excepts) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  *__flagp = __fcsr & __excepts & FE_ALL_EXCEPT;
-  return 0;
-}
-
-int fesetexceptflag(const fexcept_t* __flagp, int __excepts) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  /* Ensure that flags are all legal */
-  __excepts &= FE_ALL_EXCEPT;
-  __fcsr &= ~__excepts;
-  __fcsr |= *__flagp & __excepts;
-  fesetenv(&__fcsr);
-  return 0;
-}
-
-int feraiseexcept(int __excepts) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  /* Ensure that flags are all legal */
-  __excepts &= FE_ALL_EXCEPT;
-  /* Cause bit needs to be set as well for generating the exception*/
-  __fcsr |= __excepts | (__excepts << FCSR_CAUSE_SHIFT);
-  fesetenv(&__fcsr);
-  return 0;
-}
-
-int fetestexcept(int __excepts) {
-  fexcept_t __FCSR;
-  fegetenv(&__FCSR);
-  return (__FCSR & __excepts & FE_ALL_EXCEPT);
-}
-
-int fegetround(void) {
-  fenv_t _fcsr;
-  fegetenv(&_fcsr);
-  return (_fcsr & FCSR_RMASK);
-}
-
-int fesetround(int __round) {
-  fenv_t _fcsr;
-  fegetenv(&_fcsr);
-  _fcsr &= ~FCSR_RMASK;
-  _fcsr |= (__round & FCSR_RMASK);
-  fesetenv(&_fcsr);
-  return 0;
-}
-
-int feholdexcept(fenv_t* __envp) {
-  fenv_t __env;
-  fegetenv(&__env);
-  *__envp = __env;
-  __env &= ~(FE_ALL_EXCEPT | FCSR_ENABLE_MASK);
-  fesetenv(&__env);
-  return 0;
-}
-
-int feupdateenv(const fenv_t* __envp) {
-  fexcept_t __fcsr;
-  fegetenv(&__fcsr);
-  fesetenv(__envp);
-  feraiseexcept(__fcsr & FE_ALL_EXCEPT);
-  return 0;
-}
-
-int feenableexcept(int __mask) {
-  fenv_t __old_fcsr, __new_fcsr;
-  fegetenv(&__old_fcsr);
-  __new_fcsr = __old_fcsr | (__mask & FE_ALL_EXCEPT) << FCSR_ENABLE_SHIFT;
-  fesetenv(&__new_fcsr);
-  return ((__old_fcsr >> FCSR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
-}
-
-int fedisableexcept(int __mask) {
-  fenv_t __old_fcsr, __new_fcsr;
-  fegetenv(&__old_fcsr);
-  __new_fcsr = __old_fcsr & ~((__mask & FE_ALL_EXCEPT) << FCSR_ENABLE_SHIFT);
-  fesetenv(&__new_fcsr);
-  return ((__old_fcsr >> FCSR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
-}
-
-int fegetexcept(void) {
-  fenv_t __fcsr;
-  fegetenv(&__fcsr);
-  return ((__fcsr & FCSR_ENABLE_MASK) >> FCSR_ENABLE_SHIFT);
-}
diff --git a/tests/Android.bp b/tests/Android.bp
index ccd1126..fa66f93 100644
--- a/tests/Android.bp
+++ b/tests/Android.bp
@@ -112,6 +112,7 @@
         "netinet_ip_icmp_test.cpp",
         "netinet_udp_test.cpp",
         "nl_types_test.cpp",
+        "poll_test.cpp",
         "pthread_test.cpp",
         "pty_test.cpp",
         "regex_test.cpp",
diff --git a/tests/poll_test.cpp b/tests/poll_test.cpp
new file mode 100644
index 0000000..2a3e5e0
--- /dev/null
+++ b/tests/poll_test.cpp
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#include <gtest/gtest.h>
+
+#include <errno.h>
+#include <poll.h>
+
+TEST(poll, poll_null_fds) {
+  // Because nanosleep(2) is relatively new to POSIX, code sometimes abuses poll.
+  errno = 0;
+  ASSERT_EQ(0, poll(nullptr, 0, 1));
+  ASSERT_EQ(0, errno);
+}
+
+TEST(poll, ppoll_null_fds) {
+  // Because nanosleep(2) is relatively new to POSIX, code sometimes abuses poll.
+  errno = 0;
+  timespec ts = { .tv_nsec = 100 };
+  ASSERT_EQ(0, ppoll(nullptr, 0, &ts, nullptr));
+  ASSERT_EQ(0, errno);
+}
+
+TEST(poll, ppoll64_null_fds) {
+#if __BIONIC__
+  // Because nanosleep(2) is relatively new to POSIX, code sometimes abuses poll.
+  errno = 0;
+  timespec ts = { .tv_nsec = 100 };
+  ASSERT_EQ(0, ppoll64(nullptr, 0, &ts, nullptr));
+  ASSERT_EQ(0, errno);
+#endif
+}