[bootstrap-O1] enlarge sprintf output buffer to avoid warning

[Alexandre Oliva]

In stage2 of bootstrap-O1, the code that warns if sprintf might
overflow its output buffer cannot tell that an unsigned value narrowed
to 16 bits will fit in 4 bytes with %4x.

I couldn't find a better way to avoid the warning at -O1 than growing
the buffer so that there's no doubt the output will fit.

Regstrapped on x86_64-linux-gnu and i686-linux-gnu.  Ok to install?

for  gcc/c-family/ChangeLog

	* c-pretty-print.c (pp_c_tree_decl_identifier): Grow static
	buffer to avoid false-positive warning.
---
 gcc/c-family/c-pretty-print.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gcc/c-family/c-pretty-print.c b/gcc/c-family/c-pretty-print.c
index c32d0a0..dc6856a 100644
--- a/gcc/c-family/c-pretty-print.c
+++ b/gcc/c-family/c-pretty-print.c
@@ -2375,7 +2375,8 @@ pp_c_tree_decl_identifier (c_pretty_printer *pp, tree t)
     name = IDENTIFIER_POINTER (DECL_NAME (t));
   else
     {
-      static char xname[8];
+      /* xname[8] would do, but at -O1 we can't tell it's enough.  */
+      static char xname[12];
       sprintf (xname, "<U%4x>", ((unsigned)((uintptr_t)(t) & 0xffff)));
       name = xname;
     }


-- 
Alexandre Oliva, freedom fighter    http://FSFLA.org/~lxoliva/
You must be the change you wish to see in the world. -- Gandhi
Be Free! -- http://FSFLA.org/   FSF Latin America board member
Free Software Evangelist|Red Hat Brasil GNU Toolchain Engineer