> On IRIX 6.5, copysignf() exists in libm (at least for certain target ABIs)
> but is not unconditionally declared in the header files. As a result,
> gnulib did not detect this function and provided a replacement - but without
> the rpl_ prefix. Instead the system function can be used.
But for remainderf() the situation is opposite: It is undeclared on IRIX 6.5
and buggy. remainderf (9.316161e+37f, 0.5475547314f) goes into an endless loop.
Similarly for fma() and fmal() which are buggy if not replaced:
__round_d: bad mantissa (0000000000000000)
test-fma2.h:538: assertion failed
FAIL: test-fma2
test-fma1.h:137: assertion failed
FAIL: test-fmal1
test-fma2.h:93: assertion failed
FAIL: test-fmal2
2012-03-08 Bruno Haible <br...@clisp.org>
remainderf: Override buggy system function on IRIX 6.5.
* m4/remainderf.m4 (gl_FUNC_REMAINDERF_WORKS): New macro.
(gl_FUNC_REMAINDERF): Invoke it. Don't assume remainderf() is declared
when it exists.
* doc/posix-functions/remainderf.texi: Mention the IRIX problems.
--- doc/posix-functions/remainderf.texi.orig Thu Mar 8 11:59:05 2012
+++ doc/posix-functions/remainderf.texi Thu Mar 8 11:30:22 2012
@@ -10,7 +10,13 @@
@itemize
@item
This function is missing on some platforms:
-Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 9, MSVC 9.
+Minix 3.1.8, AIX 5.1, HP-UX 11, older IRIX 6.5, Solaris 9, MSVC 9.
+@item
+This function is not declared on some platforms:
+IRIX 6.5.
+@item
+This function may go into an endless loop on some platforms:
+IRIX 6.5.
@end itemize
Portability problems fixed by Gnulib module @code{remainderf-ieee}:
--- m4/remainderf.m4.orig Thu Mar 8 11:59:06 2012
+++ m4/remainderf.m4 Thu Mar 8 11:29:12 2012
@@ -1,4 +1,4 @@
-# remainderf.m4 serial 4
+# remainderf.m4 serial 5
dnl Copyright (C) 2012 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -26,6 +26,11 @@
# define __NO_MATH_INLINES 1 /* for glibc */
#endif
#include <math.h>
+ extern
+ #ifdef __cplusplus
+ "C"
+ #endif
+ float remainderf (float, float);
float (*funcptr) (float, float) = remainderf;
float x;
float y;]],
@@ -37,6 +42,16 @@
LIBS="$save_LIBS"
if test $gl_cv_func_remainderf = yes; then
REMAINDERF_LIBM="$REMAINDER_LIBM"
+
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $REMAINDERF_LIBM"
+ gl_FUNC_REMAINDERF_WORKS
+ LIBS="$save_LIBS"
+ case "$gl_cv_func_remainderf_works" in
+ *yes) ;;
+ *) REPLACE_REMAINDERF=1 ;;
+ esac
+
m4_ifdef([gl_FUNC_REMAINDERF_IEEE], [
if test $gl_remainderf_required = ieee && test $REPLACE_REMAINDERF = 0;
then
AC_CACHE_CHECK([whether remainderf works according to ISO C 99 with
IEC 60559],
@@ -50,6 +65,11 @@
# define __NO_MATH_INLINES 1 /* for glibc */
#endif
#include <math.h>
+extern
+#ifdef __cplusplus
+"C"
+#endif
+float remainderf (float, float);
/* Compare two numbers with ==.
This is a separate function because IRIX 6.5 "cc -O" miscompiles an
'x == x' test. */
@@ -117,3 +137,48 @@
fi
AC_SUBST([REMAINDERF_LIBM])
])
+
+dnl Test whether remainderf() works.
+dnl It runs into an endless loop on IRIX 6.5.
+AC_DEFUN([gl_FUNC_REMAINDERF_WORKS],
+[
+ AC_REQUIRE([AC_PROG_CC])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ AC_CHECK_FUNCS_ONCE([alarm])
+ AC_CACHE_CHECK([whether remainderf works], [gl_cv_func_remainderf_works],
+ [
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#include <math.h>
+#if HAVE_ALARM
+# include <unistd.h>
+#endif
+extern
+#ifdef __cplusplus
+"C"
+#endif
+float remainderf (float, float);
+volatile float x;
+volatile float y;
+float z;
+int main ()
+{
+#if HAVE_ALARM
+ alarm (5);
+#endif
+ /* This test fails on IRIX 6.5. */
+ x = 9.316161e+37f;
+ y = 0.5475547314f;
+ z = remainderf (x, y);
+ return 0;
+}
+]])],
+ [gl_cv_func_remainderf_works=yes],
+ [gl_cv_func_remainderf_works=no],
+ [case "$host_os" in
+ irix*) gl_cv_func_remainderf_works="guessing no";;
+ *) gl_cv_func_remainderf_works="guessing yes";;
+ esac
+ ])
+ ])
+])
