This is gcc-4.3.3 in Gentoo, compiled with CHOST=i686-pc-linux-gnu and the configure arguments: --prefix=/usr --bindir=/usr/i686-pc-linux-gnu/gcc-bin/4.3.3 --includedir=/usr/lib/gcc/i686-pc-linux-gnu/4.3.3/include --datadir=/usr/share/gcc-data/i686-pc-linux-gnu/4.3.3 --mandir=/usr/share/gcc-data/i686-pc-linux-gnu/4.3.3/man --infodir=/usr/share/gcc-data/i686-pc-linux-gnu/4.3.3/info --with-gxx-include-dir=/usr/lib/gcc/i686-pc-linux-gnu/4.3.3/include/g++-v4 --host=i686-pc-linux-gnu --build=i686-pc-linux-gnu --disable-altivec --disable-fixed-point --enable-nls --without-included-gettext --with-system-zlib --disable-checking --disable-werror --enable-secureplt --disable-multilib --enable-libmudflap --disable-libssp --enable-libgomp --enable-cld --enable-java-awt=gtk --with-arch=i686 --enable-languages=c,c++,java,treelang,fortran --enable-shared --enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu --with-bugurl=http://bugs.gentoo.org/ --with-pkgversion='Gentoo 4.3.3-r2 p1.1, pie-10.1.5'
Some simple code works with -O1 but not -O2. I'll attach the C file and the disassembly from objdump. I'm no good with assembly, but I find it weird that 'last' is decremented by 8 at one point. -- Summary: Bad assembly for -O2 Product: gcc Version: 4.3.3 Status: UNCONFIRMED Severity: major Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: markus at cs dot wisc dot edu GCC build triplet: i686-pc-linux-gnu GCC host triplet: i686-pc-linux-gnu GCC target triplet: i686-pc-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40087