[PATCH 1/3] libgcc: check for fenv.h in dfp configure check

[Bernhard Reutner-Fischer]

uClibc can be built without fenv support, extend the configure check for
decimal floating point to probe the existance of fenv.h, too.

libgcc/ChangeLog:

2013-03-24  Bernhard Reutner-Fischer  <al...@gcc.gnu.org>

        * configure.ac (libgcc_cv_dfp): Extend check to probe fenv.h
        availability.
        * configure: Regenerate

Signed-off-by: Bernhard Reutner-Fischer <rep.dot....@gmail.com>
---
 libgcc/configure    |   13 +++++++++++++
 libgcc/configure.ac |    9 ++++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/libgcc/configure b/libgcc/configure
index 1425df6..90936e8 100644
--- a/libgcc/configure
+++ b/libgcc/configure
@@ -4048,7 +4048,20 @@ if test "${libgcc_cv_dfp+set}" = set; then :
 else
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
+
+#include <fenv.h>
+
+int
+main ()
+{
+
 _Decimal32 x;
+int fe_except =
+  FE_INVALID|FE_DIVBYZERO|FE_OVERFLOW|FE_UNDERFLOW|FE_INEXACT;
+
+  ;
+  return 0;
+}
 _ACEOF
 if ac_fn_c_try_compile "$LINENO"; then :
   libgcc_cv_dfp=yes
diff --git a/libgcc/configure.ac b/libgcc/configure.ac
index 8b7aba5..e3d713d 100644
--- a/libgcc/configure.ac
+++ b/libgcc/configure.ac
@@ -172,7 +172,14 @@ AC_SUBST(long_double_type_size)
 
 # Check for decimal float support.
 AC_CACHE_CHECK([whether decimal floating point is supported], [libgcc_cv_dfp],
-              [AC_COMPILE_IFELSE([_Decimal32 x;], [libgcc_cv_dfp=yes],
+              [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+#include <fenv.h>
+]], [[
+_Decimal32 x;
+int fe_except =
+  FE_INVALID|FE_DIVBYZERO|FE_OVERFLOW|FE_UNDERFLOW|FE_INEXACT;
+]])],
+                                 [libgcc_cv_dfp=yes],
                                  [libgcc_cv_dfp=no])])
 decimal_float=$libgcc_cv_dfp
 AC_SUBST(decimal_float)
-- 
1.7.10.4