Because it's the semantics of libcall sequences. My take is that the
lower subreg pass breaks it in this case.
I could "fix" it at -O2 with -fno-split-wide-types or at -O1 with
-fno-move-loop-invariants or -fno-split-wide-types.
Can you also check -fno-forward-propagate?
Yes. It'll have to wait until Wednesday, though.
Ok.
Still, last time everybody spoke about removing libcall notes, the last
reason to keep them was elimination of redundant computation for TLS.
This patch should have made it redundant:
http://gcc.gnu.org/ml/gcc-patches/2005-11/msg01695.html
Paolo
