gcc: fix strict alignment.

From the OpenBSD log:

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.

Obtained from:	OpenBSD (CVS rev 1.4)
MFC after:	1 week
This commit is contained in:
Pedro F. Giffuni 2014-05-02 16:15:34 +00:00
parent c16bac236c
commit cd85ba9385

View File

@ -14408,7 +14408,7 @@ 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;
}