-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 2013-04-17 06:07:47 -0400, Dimitry Andric wrote: > On Apr 17, 2013, at 07:31, Jan Beich <jbeich_at_tormail.org> wrote: >> Dimitry Andric <dim_at_FreeBSD.org> writes: On Apr 16, 2013, at >> 00:42, Jan Beich <jbeich_at_tormail.org> wrote: > ... >>>> Maybe -O3 overoptimizes regex in libc e.g., >>>> >>>> $ echo '#if _at_GNULIB_EUIDACCESS_at_' | sed >>>> 's/_at_GNULIB_EUIDACCESS_at_/0/' #if _at_GNULIB_EUIDACCESS_at_ >>>> >>>> $ echo 'aaaaaaaaaaaaaaaaxxxaaaa' | sed >>>> 's/aaaaaaaaaaaaxxxaaaa//' aaaaaaaaaaaaaaaaxxxaaaa >>> >>> How did you arrive at this result? >> >> 1/ chroot into poudriere jail for /head amd64 2/ echo CFLAGS+=-O3 >> >> /etc/make.conf 3/ make -j2 (in /usr/src/lib/libc) 4/ prepend >> LD_LIBRARY_PATH=. before sed(1) 5/ rebuild regcomp.o, regcomp.So >> with -O2 to confirm > > I have been able to reproduce this on amd64, with -O3, but not on > i386. It seems regcomp() is either miscompiled at -O3, or it > contains some bug triggered only by the vectorizer. I am still > investigating. ... With "-fno-vectorize", this problem doesn't seem to happen. FYI, Jung-uk Kim -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (FreeBSD) iQEcBAEBAgAGBQJRbvUHAAoJECXpabHZMqHOekEIAIml2te9436LzTFsr794y82E Vmytl95H+vW9Nj0qK5X/DkB/0MSepL5FZqKF5CSNTXFoNJoVFewYRIH/H5oICSpZ jfS4evF9i2mEDOScTyC/XaucvcVWupLE9Kf7FHEk5YIhDMs4r4nzwMFGkzffEqPK yLkV/Cpc8xjvi28OuXd1KaPIcX3S8Z9vEmWPyljtseRv9WlC5gT44fSz18hmqYmv fWSiML4YKKkDRAPOCy/Shpf5QUcygOul7Jz8RiDBx3O4R5goGW8Ee8Napn7UulSL nAXTHy8dcSbiAqqPKeXhmZGPCotj++P9s3jEvunOxL7lvrdjfy3WtGedcp02ia8= =jwYS -----END PGP SIGNATURE-----Received on Wed Apr 17 2013 - 17:19:13 UTC
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