[Bug c/52734] Incorrect optimization of uClibc sbrk()

[mikpe at it dot uu.se]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52734

--- Comment #2 from Mikael Pettersson <mikpe at it dot uu.se> 2012-03-27 07:42:46 UTC ---
Created attachment 27008
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27008
adjusted test case

This test case (adjusted to __builtin_abort() on error) fails with
gcc-4.7-20120324 with -Os/-O2/-O3 on x86_64-pc-linux-gnu, but works with
-O0/-O1, and works with gcc-4.6.3 and any -O option.