md5.c (md5_finish_ctx): Declare swap_bytes.

2012-07-27  Mike Frysinger  <vapier@gentoo.org>

	* md5.c (md5_finish_ctx): Declare swap_bytes.  Assign SWAP() output
	to swap_bytes, and then call memcpy to move it to ctx->buffer.

From-SVN: r189996

libiberty/ChangeLog

+2012-07-31  Mike Frysinger  <vapier@gentoo.org>
+
+	* md5.c (md5_finish_ctx): Declare swap_bytes.  Assign SWAP() output
+	to swap_bytes, and then call memcpy to move it to ctx->buffer.
+
 2012-07-26  Kazu Hirata  <kazu@codesourcery.com>
 	    Sandra Loosemore  <sandra@codesourcery.com>
 

libiberty/md5.c

@@ -103,6 +103,7 @@ md5_finish_ctx (struct md5_ctx *ctx, void *resbuf)
 {
   /* Take yet unprocessed bytes into account.  */
   md5_uint32 bytes = ctx->buflen;
+  md5_uint32 swap_bytes;
   size_t pad;
 
   /* Now count remaining bytes.  */
@@ -113,10 +114,13 @@ md5_finish_ctx (struct md5_ctx *ctx, void *resbuf)
   pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes;
   memcpy (&ctx->buffer[bytes], fillbuf, pad);
 
-  /* Put the 64-bit file length in *bits* at the end of the buffer.  */
-  *(md5_uint32 *) &ctx->buffer[bytes + pad] = SWAP (ctx->total[0] << 3);
-  *(md5_uint32 *) &ctx->buffer[bytes + pad + 4] = SWAP ((ctx->total[1] << 3) |
-							(ctx->total[0] >> 29));
+  /* Put the 64-bit file length in *bits* at the end of the buffer.
+     Use memcpy to avoid aliasing problems.  On most systems, this
+     will be optimized away to the same code.  */
+  swap_bytes = SWAP (ctx->total[0] << 3);
+  memcpy (&ctx->buffer[bytes + pad], &swap_bytes, sizeof (swap_bytes));
+  swap_bytes = SWAP ((ctx->total[1] << 3) | (ctx->total[0] >> 29));
+  memcpy (&ctx->buffer[bytes + pad + 4], &swap_bytes, sizeof (swap_bytes));
 
   /* Process last bytes.  */
   md5_process_block (ctx->buffer, bytes + pad + 8, ctx);