[patch libbacktrace]: Fix undeclared-symbols warning for SjLj-targets

[Kai Tietz]

Hi,

this patch cleans up a undeclared-symbol issue in libbacktrace.
ChangeLog

2013-01-18  Kai Tietz  <kti...@redhat.com>

        * backtrace.c (_Unwind_GetIPInfo): Add prototype.
        * simple.c (_Unwind_GetIPInfo): Likewise.

Tested for x86_64-w64-mingw32, and i686-w64-mingw32.  Ok for apply?

Kai

Index: backtrace.c
===================================================================
--- backtrace.c (Revision 195288)
+++ backtrace.c (Arbeitskopie)
@@ -55,6 +55,8 @@ struct backtrace_data
   int ret;
 };

+extern uintptr_t _Unwind_GetIPInfo (struct _Unwind_Context *, int *);
+
 /* Unwind library callback routine.  This is passed to
    _Unwind_Backtrace.  */

Index: simple.c
===================================================================
--- simple.c    (Revision 195288)
+++ simple.c    (Arbeitskopie)
@@ -35,6 +35,8 @@ POSSIBILITY OF SUCH DAMAGE.  */
 #include "unwind.h"
 #include "backtrace.h"

+extern uintptr_t _Unwind_GetIPInfo (struct _Unwind_Context *, int *);
+
 /* The simple_backtrace routine.  */

 /* Data passed through _Unwind_Backtrace.  */