On 06/24/14 14:05, Paul Gortmaker wrote:
We see the following on a 32bit gcc installed on 64 bit host:Reading symbols from ./i586-pokymllib32-linux-gcc...done. (gdb) run Starting program: x86-pokymllib32-linux/lib32-gcc/4.9.0-r0/image/usr/bin/i586-pokymllib32-linux-gcc Program received signal SIGSEGV, Segmentation fault. 0xf7e957e0 in free () from /lib/i386-linux-gnu/libc.so.6 (gdb) bt #0 0xf7e957e0 in free () from /lib/i386-linux-gnu/libc.so.6 #1 0x0804b73c in set_multilib_dir () at gcc-4.9.0/gcc/gcc.c:7827 #2 main (argc=1, argv=0xffffd504) at gcc-4.9.0/gcc/gcc.c:6688 (gdb) The problem arises because we conditionally assign the pointer we eventually free, and the conditional may assign the pointer to the non-malloc'd internal string "." which fails when we free it here: if (multilib_dir == NULL && multilib_os_dir != NULL && strcmp (multilib_os_dir, ".") == 0) { free (CONST_CAST (char *, multilib_os_dir)); ... As suggested by Jakub, ensure the "." case is also malloc'd via xstrdup() and hence the pointer for the "." case can be freed. Cc: Jakub Jelinek <ja...@redhat.com> Cc: Jeff Law <l...@redhat.com> Cc: Matthias Klose <d...@ubuntu.com> CC: Tobias Burnus <bur...@net-b.de> Signed-off-by: Paul Gortmaker <paul.gortma...@windriver.com> --- [v2: don't change the causality of the free() ; instead just make the "." pointer be malloc'd as well. Note that I was unable to reproduce the broken-ness of my original (broken) patch with a direct build of trunk, with "./configure --prefix=/usr/local" but I also did re-test this new patch still fixed the error that we saw in yocto with gcc-4.9.0 with the invalid free segfault.] gcc/gcc.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
THanks. Installed on the trunk.
