[Bug target/55108] bad compile-time evaluation of members of initialized union

[mikpe at it dot uu.se]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55108

--- Comment #4 from Mikael Pettersson <mikpe at it dot uu.se> 2013-02-03 23:24:37 UTC ---
On armv5tel-linux-gnueabi this bug is reproducible with gcc-4.6 but not with
gcc-4.7 or 4.8.

The wrong-code was made latent for 4.7.0 by r179556 aka PR38885, a
missed-optimization fix.  Bisecting with that fix disabled (a simple #if 0 /
#endif wrapper around the new code) showed that the wrong-code was fixed
properly for 4.8 by r187648 aka PR53352, a fix for incorrect CSE of unions on
ARM.

Backporting r187648 to 4.6 fixes this PR's test case with 4.6 on armv5tel. 
Anyone backporting r187648 to 4.7 or 4.6 should also backport the test case
fixup in r187654.