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[Bug c/40087] New: Bad assembly for -O2
- From: "markus at cs dot wisc dot edu" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 10 May 2009 01:39:00 -0000
- Subject: [Bug c/40087] New: Bad assembly for -O2
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
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