From: martynas <martynas@openbsd.org>
Date: Thu, 1 May 2014 14:15:42 +0000 (+0000)
Subject: x86-64 ABI requires arrays greater than 16 bytes to be aligned to
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=3ee6095e0d36ba0260edfda78c0efa2e1f1073de;p=openbsd

x86-64 ABI requires arrays greater than 16 bytes to be aligned to
16byte boundary.  However, GCC 16-byte aligns arrays of >=16 BITS,
not BYTES.

This diff improves bug detectability for code which has local arrays
of [16 .. 127] bits:  in those cases SSP will now detect even 1-byte
overflows.

OK kettenis@.  Tested in snaps for a week.
---

diff --git a/gnu/gcc/gcc/config/i386/i386.c b/gnu/gcc/gcc/config/i386/i386.c
index 5abc9432967..6fab6d81312 100644
--- a/gnu/gcc/gcc/config/i386/i386.c
+++ b/gnu/gcc/gcc/config/i386/i386.c
@@ -14051,7 +14051,7 @@ ix86_local_alignment (tree type, int align)
       if (AGGREGATE_TYPE_P (type)
 	   && TYPE_SIZE (type)
 	   && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
-	   && (TREE_INT_CST_LOW (TYPE_SIZE (type)) >= 16
+	   && (TREE_INT_CST_LOW (TYPE_SIZE (type)) >= 128
 	       || TREE_INT_CST_HIGH (TYPE_SIZE (type))) && align < 128)
 	return 128;
     }