ext2fs: fix warning: 'blocknxt' may be used uninitialized with gcc 4.2
authorTom Rini <trini@ti.com>
Tue, 7 Aug 2012 16:58:34 +0000 (09:58 -0700)
committerWolfgang Denk <wd@denx.de>
Tue, 7 Aug 2012 18:52:42 +0000 (20:52 +0200)
The above warning was introduced originally in 436da3c "ext2load:
increase read speed" and fixed for newer toolchains in b803273 "ext2fs:
fix warning: 'blocknxt' may be used uninitialized".  This change did not
fix the warning with gcc 4.2, as found in ELDK 4.2.

If we rework the while loop to initalize blocknxt before entering the
warning really goes away.  Tested on am335x with an approx 7mb file and
crc32 in U-Boot befor and after this change.

Cc: Wolfgang Denk <wd@denx.de>
Cc: Eric Nelson <eric.nelson@boundarydevices.com>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Jason Cooper <u-boot@lakedaemon.net>
Cc: Andreas Bießmann <andreas.devel@googlemail.com>
Cc: Reinhard Arlt <reinhard.arlt@esd-electronics.com>
Cc: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Tom Rini <trini@ti.com>
fs/ext2/ext2fs.c

index 182f0ac..418404e 100644 (file)
@@ -440,9 +440,8 @@ int ext2fs_read_file
                /* grab middle blocks in one go */
                if (i != pos / blocksize && i < blockcnt - 1 && blockcnt > 3) {
                        int oldblk = blknr;
-                       int blocknxt;
+                       int blocknxt = ext2fs_read_block(node, i + 1);
                        while (i < blockcnt - 1) {
-                               blocknxt = ext2fs_read_block(node, i + 1);
                                if (blocknxt == (oldblk + 1)) {
                                        oldblk = blocknxt;
                                        i++;
@@ -450,6 +449,7 @@ int ext2fs_read_file
                                        blocknxt = ext2fs_read_block(node, i);
                                        break;
                                }
+                               blocknxt = ext2fs_read_block(node, i);
                        }
 
                        if (oldblk == blknr)