1# hypotf.m4 serial 10 2dnl Copyright (C) 2012-2021 Free Software Foundation, Inc. 3dnl This file is free software; the Free Software Foundation 4dnl gives unlimited permission to copy and/or distribute it, 5dnl with or without modifications, as long as this notice is preserved. 6 7AC_DEFUN([gl_FUNC_HYPOTF], 8[ 9 m4_divert_text([DEFAULTS], [gl_hypotf_required=plain]) 10 AC_REQUIRE([gl_MATH_H_DEFAULTS]) 11 AC_REQUIRE([gl_FUNC_HYPOT]) 12 13 dnl Persuade glibc <math.h> to declare hypotf(). 14 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) 15 16 dnl Test whether hypotf() exists. Assume that hypotf(), if it exists, is 17 dnl defined in the same library as hypot(). 18 save_LIBS="$LIBS" 19 LIBS="$LIBS $HYPOT_LIBM" 20 AC_CHECK_FUNCS([hypotf]) 21 LIBS="$save_LIBS" 22 if test $ac_cv_func_hypotf = yes; then 23 HYPOTF_LIBM="$HYPOT_LIBM" 24 25 save_LIBS="$LIBS" 26 LIBS="$LIBS $HYPOTF_LIBM" 27 gl_FUNC_HYPOTF_WORKS 28 LIBS="$save_LIBS" 29 case "$gl_cv_func_hypotf_works" in 30 *yes) ;; 31 *) REPLACE_HYPOTF=1 ;; 32 esac 33 34 m4_ifdef([gl_FUNC_HYPOTF_IEEE], [ 35 if test $gl_hypotf_required = ieee && test $REPLACE_HYPOTF = 0; then 36 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles 37 AC_CACHE_CHECK([whether hypotf works according to ISO C 99 with IEC 60559], 38 [gl_cv_func_hypotf_ieee], 39 [ 40 save_LIBS="$LIBS" 41 LIBS="$LIBS $HYPOTF_LIBM" 42 AC_RUN_IFELSE( 43 [AC_LANG_SOURCE([[ 44#ifndef __NO_MATH_INLINES 45# define __NO_MATH_INLINES 1 /* for glibc */ 46#endif 47#include <math.h> 48/* Compare two numbers with ==. 49 This is a separate function because IRIX 6.5 "cc -O" miscompiles an 50 'x == x' test. */ 51static int 52numeric_equal (float x, float y) 53{ 54 return x == y; 55} 56static float dummy (float x, float y) { return 0; } 57float zero; 58float one = 1.0f; 59int main (int argc, char *argv[]) 60{ 61 float (* volatile my_hypotf) (float, float) = argc ? hypotf : dummy; 62 float f; 63 /* Test hypotf(NaN,Infinity). 64 This test fails on OSF/1 5.1 and native Windows. */ 65 f = my_hypotf (zero / zero, one / zero); 66 if (!numeric_equal (f, f)) 67 return 1; 68 return 0; 69} 70 ]])], 71 [gl_cv_func_hypotf_ieee=yes], 72 [gl_cv_func_hypotf_ieee=no], 73 [case "$host_os" in 74 # Guess yes on glibc systems. 75 *-gnu* | gnu*) gl_cv_func_hypotf_ieee="guessing yes" ;; 76 # Guess yes on musl systems. 77 *-musl*) gl_cv_func_hypotf_ieee="guessing yes" ;; 78 # Guess yes on native Windows. 79 mingw*) gl_cv_func_hypotf_ieee="guessing yes" ;; 80 # If we don't know, obey --enable-cross-guesses. 81 *) gl_cv_func_hypotf_ieee="$gl_cross_guess_normal" ;; 82 esac 83 ]) 84 LIBS="$save_LIBS" 85 ]) 86 case "$gl_cv_func_hypotf_ieee" in 87 *yes) ;; 88 *) REPLACE_HYPOTF=1 ;; 89 esac 90 fi 91 ]) 92 else 93 HAVE_HYPOTF=0 94 dnl If the function is declared but does not appear to exist, it may be 95 dnl defined as an inline function. In order to avoid a conflict, we have 96 dnl to define rpl_hypotf, not hypotf. 97 AC_CHECK_DECLS([hypotf], [REPLACE_HYPOTF=1], , [[#include <math.h>]]) 98 fi 99 if test $HAVE_HYPOTF = 0 || test $REPLACE_HYPOTF = 1; then 100 dnl Find libraries needed to link lib/hypotf.c. 101 HYPOTF_LIBM="$HYPOT_LIBM" 102 fi 103 AC_SUBST([HYPOTF_LIBM]) 104]) 105 106dnl Test whether hypotf() works. 107dnl It returns wrong values on NetBSD 5.1/x86_64 and OpenBSD 4.9/x86. 108AC_DEFUN([gl_FUNC_HYPOTF_WORKS], 109[ 110 AC_REQUIRE([AC_PROG_CC]) 111 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles 112 AC_CACHE_CHECK([whether hypotf works], [gl_cv_func_hypotf_works], 113 [ 114 AC_RUN_IFELSE( 115 [AC_LANG_SOURCE([[ 116#include <float.h> 117#include <math.h> 118volatile float x; 119volatile float y; 120volatile float z; 121int main () 122{ 123 int result = 0; 124 /* This test fails on NetBSD 5.1. */ 125 { 126 x = FLT_MIN * 2.0f; 127 y = FLT_MIN * 3.0f; 128 z = hypotf (x, y); 129 if (!(z >= FLT_MIN * 2.0f && z <= FLT_MIN * 4.0f)) 130 result |= 1; 131 } 132 /* This test fails on OpenBSD 4.9. */ 133 { 134 x = FLT_MAX; 135 y = FLT_MAX * 0.5f; 136 z = hypotf (x, y); 137 if (!(z > 0 && z == z + z)) 138 result |= 2; 139 } 140 return result; 141} 142]])], 143 [gl_cv_func_hypotf_works=yes], 144 [gl_cv_func_hypotf_works=no], 145 [case "$host_os" in 146 netbsd* | openbsd*) gl_cv_func_hypotf_works="guessing no" ;; 147 # Guess yes on native Windows. 148 mingw*) gl_cv_func_hypotf_works="guessing yes" ;; 149 *) gl_cv_func_hypotf_works="guessing yes" ;; 150 esac 151 ]) 152 ]) 153]) 154