http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56888
Rich Felker <bugdal at aerifal dot cx> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |bugdal at aerifal dot cx
--- Comment #19 from Rich Felker <bugdal at aerifal dot cx> ---
We are not presently experiencing this issue in musl libc, probably because the
current C memcpy code is sufficiently overcomplicated to avoid getting detected
by the optimizer as memcpy. However, I'm trying to switch to a new simpler
implementation that's much faster when compiled with GCC 4.7.1 (on ARM), but
hit this bug when testing on another system using GCC 4.6.1 (ARM). On the
latter, even -fno-tree-loop-distribute-patterns does not make any difference.
Unless there's a reliable workaround for this bug or at least a known blacklist
of bad GCC versions where this bug can't be worked around, I'm afraid we're
going to have to resort to generating the asm for each supported arch using a
known-good GCC and including that asm in the distribution.
This is EXTREMELY frustrating.
