https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69463
Bug ID: 69463 Summary: wrong code with -O1 and vector arithmetics @ x86_64 Product: gcc Version: 6.0 Status: UNCONFIRMED Keywords: wrong-code Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: zsojka at seznam dot cz Target Milestone: --- Host: x86_64-pc-linux-gnu Target: x86_64-* Created attachment 37457 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=37457&action=edit reduced testcase Maybe related to PR69459. This testcase is failing for all versions that are able to compile it (gcc-4_9-branch needs -O2 to reproduce). Fails only for x86_64-pc-linux-gnu*. i686-* might fail as well with proper -march= switch. aarch64-*, armv7a-*, powerpc-*, powerpc64-*, sparc-*, sparc64-* do not fail at any -On level. Output: $ x86_64-pc-linux-gnu-gcc -v Using built-in specs. COLLECT_GCC=/repo/gcc-trunk/binary-latest/bin/x86_64-pc-linux-gnu-gcc COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-232760-checking-yes-rtl-df-nographite/bin/../libexec/gcc/x86_64-pc-linux-gnu/6.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++ --enable-checking=yes,rtl,df --without-cloog --without-ppl --without-isl --disable-libstdcxx-pch --prefix=/repo/gcc-trunk//binary-trunk-232760-checking-yes-rtl-df-nographite Thread model: posix gcc version 6.0.0 20160123 (experimental) (GCC) $ x86_64-pc-linux-gnu-gcc -O testcase.c $ ./a.out 0000000100000107 ffffffff00000001 Aborted Tested revisions: trunk r232760 - FAIL 5-branch r232545 - FAIL 4_9-branch r232544 - OK @ -O1, FAIL @ -O2 4_[87]-branch - FAIL