diff --git a/libc/include/android/legacy_fenv_inlines_arm.h b/libc/include/android/legacy_fenv_inlines_arm.h
new file mode 100644
index 0000000..a5bb26b
--- /dev/null
+++ b/libc/include/android/legacy_fenv_inlines_arm.h
@@ -0,0 +1,154 @@
+/*-
+ * 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 $
+ */
+
+#ifndef ANDROID_LEGACY_FENV_INLINES_ARM_H
+#define ANDROID_LEGACY_FENV_INLINES_ARM_H
+
+#include <fenv.h>
+
+#if __ANDROID_API__ < 21 && defined(__arm__)
+
+__BEGIN_DECLS
+
+#define FPSCR_ENABLE_SHIFT 8
+#define FPSCR_ENABLE_MASK  (FE_ALL_EXCEPT << FPSCR_ENABLE_SHIFT)
+
+#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 | FPSCR_ENABLE_MASK);
+  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) {
+  fenv_t __old_fpscr, __new_fpscr;
+  fegetenv(&__old_fpscr);
+  __new_fpscr = __old_fpscr | (__mask & FE_ALL_EXCEPT) << FPSCR_ENABLE_SHIFT;
+  fesetenv(&__new_fpscr);
+  return ((__old_fpscr >> FPSCR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
+}
+
+static __inline int fedisableexcept(int __mask) {
+  fenv_t __old_fpscr, __new_fpscr;
+  fegetenv(&__old_fpscr);
+  __new_fpscr = __old_fpscr & ~((__mask & FE_ALL_EXCEPT) << FPSCR_ENABLE_SHIFT);
+  fesetenv(&__new_fpscr);
+  return ((__old_fpscr >> FPSCR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
+}
+
+static __inline int fegetexcept(void) {
+  fenv_t __fpscr;
+  fegetenv(&__fpscr);
+  return ((__fpscr & FPSCR_ENABLE_MASK) >> FPSCR_ENABLE_SHIFT);
+}
+
+#undef FPSCR_ENABLE_SHIFT
+#undef FPSCR_ENABLE_MASK
+#undef FPSCR_RMODE_SHIFT
+
+__END_DECLS
+
+#endif /* __ANDROID_API__ < 21 && defined(__arm__) */
+
+#endif /* ANDROID_LEGACY_FENV_INLINES_ARM_H */
diff --git a/libc/include/android/legacy_fenv_inlines_mips.h b/libc/include/android/legacy_fenv_inlines_mips.h
new file mode 100644
index 0000000..ead697c
--- /dev/null
+++ b/libc/include/android/legacy_fenv_inlines_mips.h
@@ -0,0 +1,168 @@
+/*-
+ * 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 $
+ */
+
+#ifndef ANDROID_LEGACY_FENV_INLINES_MIPS_H
+#define ANDROID_LEGACY_FENV_INLINES_MIPS_H
+
+#include <fenv.h>
+
+#if __ANDROID_API__ < 21 && (defined(__mips__) && !defined(__LP64__))
+
+__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__ < 21 && (defined(__mips__) && !defined(__LP64__)) */
+
+#endif /* ANDROID_LEGACY_FENV_INLINES_MIPS_H */
diff --git a/libc/include/fenv.h b/libc/include/fenv.h
index f1b2b25..241e845 100644
--- a/libc/include/fenv.h
+++ b/libc/include/fenv.h
@@ -36,6 +36,7 @@
 __BEGIN_DECLS
 
 // fenv was always available on x86.
+#if __ANDROID_API__ >= 21 || defined(__i386__)
 int feclearexcept(int) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 int fegetexceptflag(fexcept_t*, int) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21)
     __INTRODUCED_IN_X86(9);
@@ -56,6 +57,9 @@
 int feenableexcept(int) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 int fedisableexcept(int) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 int fegetexcept(void) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
+#else
+/* Defined as inlines for pre-21 ARM and MIPS. */
+#endif
 
 /*
  * The following constant represents the default floating-point environment
@@ -70,4 +74,7 @@
 
 __END_DECLS
 
+#include <android/legacy_fenv_inlines_arm.h>
+#include <android/legacy_fenv_inlines_mips.h>
+
 #endif  /* ! _FENV_H_ */