X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fisfinite.m4;h=b54b403b880885db06641d8e2d79fbb1f1374870;hb=72c63c089365640c7f1acd97fb72ee26932ac2b3;hp=4fb557b47bd2fc898fe71f62ea22b6cd38256b11;hpb=bfef7ab3494ed38e16363623a75c2740c8803f6e;p=gnulib.git diff --git a/m4/isfinite.m4 b/m4/isfinite.m4 index 4fb557b47..b54b403b8 100644 --- a/m4/isfinite.m4 +++ b/m4/isfinite.m4 @@ -1,5 +1,5 @@ -# isfinite.m4 serial 3 -dnl Copyright (C) 2007-2008 Free Software Foundation, Inc. +# isfinite.m4 serial 13 +dnl Copyright (C) 2007-2013 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. @@ -9,9 +9,10 @@ AC_DEFUN([gl_ISFINITE], AC_REQUIRE([gl_MATH_H_DEFAULTS]) dnl Persuade glibc to declare isfinite. AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) - AC_CHECK_DECLS([isfinite], , , [#include ]) + AC_CHECK_DECLS([isfinite], , , [[#include ]]) if test "$ac_cv_have_decl_isfinite" = yes; then - gl_CHECK_MATH_LIB([ISFINITE_LIBM], [x = isfinite (x);]) + gl_CHECK_MATH_LIB([ISFINITE_LIBM], + [x = isfinite (x) + isfinite ((float) x);]) if test "$ISFINITE_LIBM" != missing; then dnl Test whether isfinite() on 'long double' works. gl_ISFINITEL_WORKS @@ -27,10 +28,9 @@ AC_DEFUN([gl_ISFINITE], if test "$ac_cv_have_decl_isfinite" != yes || test "$ISFINITE_LIBM" = missing; then REPLACE_ISFINITE=1 - AC_LIBOBJ([isfinite]) + dnl No libraries are needed to link lib/isfinite.c. ISFINITE_LIBM= fi - AC_SUBST([REPLACE_ISFINITE]) AC_SUBST([ISFINITE_LIBM]) ]) @@ -44,11 +44,12 @@ dnl pseudo-denormals on ia64. AC_DEFUN([gl_ISFINITEL_WORKS], [ AC_REQUIRE([AC_PROG_CC]) - AC_REQUIRE([AC_C_BIGENDIAN]) + AC_REQUIRE([gl_BIGENDIAN]) + AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE]) AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles AC_CACHE_CHECK([whether isfinite(long double) works], [gl_cv_func_isfinitel_works], [ - AC_TRY_RUN([ + AC_RUN_IFELSE([AC_LANG_SOURCE([[ #include #include #include @@ -56,23 +57,38 @@ AC_DEFUN([gl_ISFINITEL_WORKS], ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) typedef union { unsigned int word[NWORDS]; long double value; } memory_long_double; +/* On Irix 6.5, gcc 3.4.3 can't compute compile-time NaN, and needs the + runtime type conversion. */ +#ifdef __sgi +static long double NaNl () +{ + double zero = 0.0; + return zero / zero; +} +#else +# define NaNl() (0.0L / 0.0L) +#endif int main () { - memory_long_double m; - unsigned int i; + int result = 0; - /* The isfinite macro should be immune against changes in the sign bit and - in the mantissa bits. The xor operation twiddles a bit that can only be - a sign bit or a mantissa bit (since the exponent never extends to - bit 31). */ - m.value = 0.0L / 0.0L; - m.word[NWORDS / 2] ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1); - for (i = 0; i < NWORDS; i++) - m.word[i] |= 1; - if (isfinite (m.value)) - return 1; + { + memory_long_double m; + unsigned int i; + + /* The isfinite macro should be immune against changes in the sign bit and + in the mantissa bits. The xor operation twiddles a bit that can only be + a sign bit or a mantissa bit (since the exponent never extends to + bit 31). */ + m.value = NaNl (); + m.word[NWORDS / 2] ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1); + for (i = 0; i < NWORDS; i++) + m.word[i] |= 1; + if (isfinite (m.value)) + result |= 1; + } -#if ((defined __ia64 && LDBL_MANT_DIG == 64) || (defined __x86_64__ || defined __amd64__) || (defined __i386 || defined __i386__ || defined _I386 || defined _M_IX86 || defined _X86_)) +#if ((defined __ia64 && LDBL_MANT_DIG == 64) || (defined __x86_64__ || defined __amd64__) || (defined __i386 || defined __i386__ || defined _I386 || defined _M_IX86 || defined _X86_)) && !HAVE_SAME_LONG_DOUBLE_AS_DOUBLE /* Representation of an 80-bit 'long double' as an initializer for a sequence of 'unsigned int' words. */ # ifdef WORDS_BIGENDIAN @@ -89,14 +105,14 @@ int main () static memory_long_double x = { LDBL80_WORDS (0xFFFF, 0xC3333333, 0x00000000) }; if (isfinite (x.value)) - return 1; + result |= 2; } { /* Signalling NaN. */ static memory_long_double x = { LDBL80_WORDS (0xFFFF, 0x83333333, 0x00000000) }; if (isfinite (x.value)) - return 1; + result |= 2; } /* The isfinite macro should recognize Pseudo-NaNs, Pseudo-Infinities, Pseudo-Zeroes, Unnormalized Numbers, and Pseudo-Denormals, as defined in @@ -109,40 +125,40 @@ int main () static memory_long_double x = { LDBL80_WORDS (0xFFFF, 0x40000001, 0x00000000) }; if (isfinite (x.value)) - return 1; + result |= 4; } { /* Pseudo-Infinity. */ static memory_long_double x = { LDBL80_WORDS (0xFFFF, 0x00000000, 0x00000000) }; if (isfinite (x.value)) - return 1; + result |= 8; } { /* Pseudo-Zero. */ static memory_long_double x = { LDBL80_WORDS (0x4004, 0x00000000, 0x00000000) }; if (isfinite (x.value)) - return 1; + result |= 16; } { /* Unnormalized number. */ static memory_long_double x = { LDBL80_WORDS (0x4000, 0x63333333, 0x00000000) }; if (isfinite (x.value)) - return 1; + result |= 32; } { /* Pseudo-Denormal. */ static memory_long_double x = { LDBL80_WORDS (0x0000, 0x83333333, 0x00000000) }; if (isfinite (x.value)) - return 1; + result |= 64; } #endif - return 0; -}], [gl_cv_func_isfinitel_works=yes], [gl_cv_func_isfinitel_works=no], + return result; +}]])], [gl_cv_func_isfinitel_works=yes], [gl_cv_func_isfinitel_works=no], [case "$host_cpu" in # Guess no on ia64, x86_64, i386. - ia64 | x86_64 | i*86) gl_cv_func_isnanl_works="guessing no";; - *) gl_cv_func_isnanl_works="guessing yes";; + ia64 | x86_64 | i*86) gl_cv_func_isfinitel_works="guessing no";; + *) gl_cv_func_isfinitel_works="guessing yes";; esac ]) ])