X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Ffloat_h.m4;h=397f2d1faa3949a427df94eda7cdd0d8ad18ebab;hb=5191b3546cfb6c163228c23f214e325ddf60d46f;hp=da11c0e2d80e2343907f848bfe6350551330587a;hpb=c65d65a81e9d66960ae7ce5abe5069d5b7338ed2;p=gnulib.git

diff --git a/m4/float_h.m4 b/m4/float_h.m4
index da11c0e2d..397f2d1fa 100644
--- a/m4/float_h.m4
+++ b/m4/float_h.m4
@@ -1,5 +1,5 @@
-# float_h.m4 serial 8
-dnl Copyright (C) 2007, 2009-2011 Free Software Foundation, Inc.
+# float_h.m4 serial 9
+dnl Copyright (C) 2007, 2009-2013 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.
@@ -48,9 +48,51 @@ changequote([,])dnl
       fi
       ;;
   esac
+
+  dnl Test against glibc-2.7 Linux/SPARC64 bug.
+  REPLACE_ITOLD=0
+  AC_CACHE_CHECK([whether conversion from 'int' to 'long double' works],
+    [gl_cv_func_itold_works],
+    [
+      AC_RUN_IFELSE(
+        [AC_LANG_SOURCE([[
+int i = -1;
+volatile long double ld;
+int main ()
+{
+  ld += i * 1.0L;
+  if (ld > 0)
+    return 1;
+  return 0;
+}]])],
+        [gl_cv_func_itold_works=yes],
+        [gl_cv_func_itold_works=no],
+        [case "$host" in
+           sparc*-*-linux*)
+             AC_EGREP_CPP([yes],
+               [#if defined __LP64__ || defined __arch64__
+                yes
+                #endif],
+               [gl_cv_func_itold_works="guessing no"],
+               [gl_cv_func_itold_works="guessing yes"])
+             ;;
+           *) gl_cv_func_itold_works="guessing yes" ;;
+         esac
+        ])
+    ])
+  case "$gl_cv_func_itold_works" in
+    *no)
+      REPLACE_ITOLD=1
+      dnl We add the workaround to <float.h> but also to <math.h>,
+      dnl to increase the chances that the fix function gets pulled in.
+      FLOAT_H=float.h
+      ;;
+  esac
+
   if test -n "$FLOAT_H"; then
     gl_NEXT_HEADERS([float.h])
   fi
   AC_SUBST([FLOAT_H])
   AM_CONDITIONAL([GL_GENERATE_FLOAT_H], [test -n "$FLOAT_H"])
+  AC_SUBST([REPLACE_ITOLD])
 ])