[AArch64/AArch64-4.7][libgcc] Silence warnings in sync-cache.c

[James Greenhalgh]

Hi,

On trunk and 4.7 __aarch64_sync_cache_range gives a missing prototype
warning and two "statement with no effect" warnings as so:

---
.../libgcc/config/aarch64/sync-cache.c:22:1: warning: no previous prototype for 
'__aarch64_sync_cache_range' [-Wmissing-prototypes]
 __aarch64_sync_cache_range (const void *base, const void *end)
 ^
.../libgcc/config/aarch64/sync-cache.c: In function 
'__aarch64_sync_cache_range':
/work/oban-clean/src/gcc/libgcc/config/aarch64/sync-cache.c:46:3: warning: 
statement with no effect [-Wunused-value]
   for (address; address < (const char *) end; address += dcache_lsize)
   ^
.../libgcc/config/aarch64/sync-cache.c:58:3: warning: statement with no effect 
[-Wunused-value]
   for (address; address < (const char *) end; address += icache_lsize)
---

This patch silences these warnings by declaring a prototype for
aarch64_sync_cache_range and removing the no-op for loop initialisation

Regression tested on aarch64-none-linux-gnu with no issues.

OK for trunk/aarch64-4.7-branch?

Thanks,
James Greenhalgh

---
libgcc/

2013-03-01  James Greenhalgh  <james.greenha...@arm.com>

        * config/aarch64/sync-cache.c
        (__aarch64_sync_cache_range): Silence warnings.

diff --git a/libgcc/config/aarch64/sync-cache.c b/libgcc/config/aarch64/sync-cache.c
index 7091c48..3397e9d 100644
--- a/libgcc/config/aarch64/sync-cache.c
+++ b/libgcc/config/aarch64/sync-cache.c
@@ -18,6 +18,8 @@
    along with GCC; see the file COPYING3.  If not see
    <http://www.gnu.org/licenses/>.  */
 
+void __aarch64_sync_cache_range (const void *, const void *);
+
 void
 __aarch64_sync_cache_range (const void *base, const void *end)
 {
@@ -43,7 +45,7 @@ __aarch64_sync_cache_range (const void *base, const void *end)
   address = (const char*) ((__UINTPTR_TYPE__) base
 			   & ~ (__UINTPTR_TYPE__) (dcache_lsize - 1));
 
-  for (address; address < (const char *) end; address += dcache_lsize)
+  for (; address < (const char *) end; address += dcache_lsize)
     asm volatile ("dc\tcvau, %0"
 		  :
 		  : "r" (address)
@@ -55,7 +57,7 @@ __aarch64_sync_cache_range (const void *base, const void *end)
   address = (const char*) ((__UINTPTR_TYPE__) base
 			   & ~ (__UINTPTR_TYPE__) (icache_lsize - 1));
 
-  for (address; address < (const char *) end; address += icache_lsize)
+  for (; address < (const char *) end; address += icache_lsize)
     asm volatile ("ic\tivau, %0"
 		  :
 		  : "r" (address)