http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58679
--- Comment #9 from Uroš Bizjak <ubizjak at gmail dot com> --- (In reply to Eric Botcazou from comment #8) > > Or should we use a different approach, and use DF to re-create REG_DEAD > > notes? > > Yes, if you need REG_DEAD/REG_UNUSED notes, just tell DF to compute them: I think that missing REG_DEAD/REG_UNUSED notes and r202915 just triggered the problem, fixed with [1] - at least I'm not able to trigger the ICE described in Comment #0 anymore. The new problem was introduced by Vladimir's patch that removed final assignments to return registers in several cases. The postreload mode-switching pass depends on them, and gcc.target/i386/{avx-1,sse-23,sse-24}.c testcases start to fail on x86 [2]. Also, bootstrap will be broken when configured with "--with-arch=core-avx-i --with-cpu=core-avx-i --with-fpmath=avx" due to post-reload mode switching failures in libjava and libgo. [1] http://gcc.gnu.org/ml/gcc-patches/2013-10/msg01606.html [2] http://gcc.gnu.org/ml/gcc-testresults/2013-10/msg02051.html