[patch] libgcc unwind-arm.h: mark arguments as unused

[Matthias Klose]

This was seen and fixed on trunk building libbacktrace on arm:
http://gcc.gnu.org/ml/gcc-patches/2012-10/msg00628.html

I see this now cross building libgo targeting arm on the 4.7 branch. Ok to
backport to the 4.7 branch?

  Matthias

2012-10-07  Matthias Klose  <d...@ubuntu.com>

        * config/arm/unwind-arm.h (__gnu_unwind_24bit): Mark parameters
        as unused.
        (_Unwind_decode_typeinfo_ptr): Mark base as unused.

--- libgcc/config/arm/unwind-arm.h~
+++ libgcc/config/arm/unwind-arm.h
@@ -39,7 +39,8 @@
 #endif
   /* Decode an R_ARM_TARGET2 relocation.  */
   static inline _Unwind_Word
-  _Unwind_decode_typeinfo_ptr (_Unwind_Word base, _Unwind_Word ptr)
+  _Unwind_decode_typeinfo_ptr (_Unwind_Word base __attribute__ ((unused)),
+                               _Unwind_Word ptr)
     {
       _Unwind_Word tmp;
 
@@ -65,7 +66,9 @@
     }
 
   static inline _Unwind_Reason_Code
-  __gnu_unwind_24bit (_Unwind_Context * context, _uw data, int compact)
+  __gnu_unwind_24bit (_Unwind_Context * context __attribute__ ((unused)),
+                      _uw data __attribute__ ((unused)),
+                      int compact __attribute__ ((unused)))
     {
       return _URC_FAILURE;
     }