[google] Hide all uses of __float128 from Clang

[simonb, 2012-05-09 15:19:01]

Hide all uses of __float128 from Clang.

Brackets _GLIBCXX_USE_FLOAT128 with #ifndef __clang__.  Clang does not
currently support the __float128 builtin, and so will fail to process
libstdc++ headers that use it.

Tested for full bootstrap and dejagnu testsuite.

Okay for google/integration and google/gcc-4_7-integration branches?

Thanks.


2012-05-09   Simon Baldwin  <simonb@google.com>

	* libstdc++-v3/acinclude.m4: Bracket _GLIBCXX_USE_FLOAT128
	definition with	ifndef __clang__.
	* libstdc++-v3/config.h.in: Rebuild.

Index: libstdc++-v3/config.h.in
===================================================================
--- libstdc++-v3/config.h.in	(revision 187148)
+++ libstdc++-v3/config.h.in	(working copy)
@@ -799,8 +799,11 @@
    this host. */
 #undef _GLIBCXX_USE_DECIMAL_FLOAT
 
-/* Define if __float128 is supported on this host. */
+/* Define if __float128 is supported on this host.
+   Hide all uses of __float128 from Clang.  Google ref b/6422845  */
+#ifndef __clang__
 #undef _GLIBCXX_USE_FLOAT128
+#endif
 
 /* Defined if gettimeofday is available. */
 #undef _GLIBCXX_USE_GETTIMEOFDAY
Index: libstdc++-v3/acinclude.m4
===================================================================
--- libstdc++-v3/acinclude.m4	(revision 187148)
+++ libstdc++-v3/acinclude.m4	(working copy)
@@ -2529,10 +2529,16 @@ int main()
 }
 EOF
 
+    AH_VERBATIM([_GLIBCXX_USE_FLOAT128,],
+                [/* Define if __float128 is supported on this host.
+   Hide all uses of __float128 from Clang.  Google ref b/6422845  */
+#ifndef __clang__
+#undef _GLIBCXX_USE_FLOAT128
+#endif])
+
     AC_MSG_CHECKING([for __float128])
     if AC_TRY_EVAL(ac_compile); then
-      AC_DEFINE(_GLIBCXX_USE_FLOAT128, 1,
-      [Define if __float128 is supported on this host.])
+      AC_DEFINE(_GLIBCXX_USE_FLOAT128, 1)
       enable_float128=yes
     else
       enable_float128=no

--
This patch is available for review at http://codereview.appspot.com/6195066

[Diego Novillo, 2012-05-09 15:28:10]

On 12-05-09 08:19 , Simon Baldwin wrote:

> 2012-05-09   Simon Baldwin<simonb@google.com>
>
> 	* libstdc++-v3/acinclude.m4: Bracket _GLIBCXX_USE_FLOAT128
> 	definition with	ifndef __clang__.
> 	* libstdc++-v3/config.h.in: Rebuild.

OK.


Diego.

[Ollie Wild, 2012-05-09 15:33:34]

On Wed, May 9, 2012 at 8:19 AM, Simon Baldwin <simonb@google.com> wrote:
>
> Hide all uses of __float128 from Clang.
>
> Brackets _GLIBCXX_USE_FLOAT128 with #ifndef __clang__.  Clang does not
> currently support the __float128 builtin, and so will fail to process
> libstdc++ headers that use it.
>
> Tested for full bootstrap and dejagnu testsuite.
>
> Okay for google/integration and google/gcc-4_7-integration branches?

Please check this into google/gcc-4_7 as well.

Ollie