[Bug bootstrap/51648] [4.7 Regression] Profiledbootstrap failure on x86_64-linux

["jakub at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51648

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-12-21 11:52:55 UTC ---
-O2 -g -fexceptions -fstack-protector --param=ssp-buffer-size=4 -mtune=generic
are our standard distro flags.  The intent is that e.g. C code that uses
pthread_cleanup_{push,pop} will be more efficient (use cleanup attribute) if we
do that.  Packages that for some reason want to build with -fno-exceptions
should IMHO put that -fno-exceptions after user supplied flags to override it.
If I understand right our gcc/Makefile.in we do that, $(NOEXCEPT_FLAGS) is put
after TCFLAGS etc. in AM_CXXFLAGS, so it overrides it right.
In this case (C build instead of C++, when there are still no advantages of
using C++ in GCC, I thought it doesn't hurt to configure that way) -fno-rtti
-fno-exceptions isn't considered to be a valid option during configure (well,
-fno-exceptions is, but -fno-rtti is not for C and both are tried at the same
time), so we build with -fexceptions.  That shouldn't make a significant
difference for C though, unless the cleanup attribute is used somewhere.

Anyway, the reason why I'm filing this is because this looks very much like
lots of the issues that were not really reproduceable during profiledbootstrap
in the past, now it seems to be reproduceable.