http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60649
Bug ID: 60649 Summary: [ASAN] Bogus "'y' may be used uninitialized" warning (affects bootstrap-asan) Product: gcc Version: 4.9.0 Status: UNCONFIRMED Keywords: build, diagnostic Severity: normal Priority: P3 Component: sanitizer Assignee: unassigned at gcc dot gnu.org Reporter: burnus at gcc dot gnu.org CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org, jakub at gcc dot gnu.org, kcc at gcc dot gnu.org Created attachment 32446 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32446&action=edit C++ Test case (test.ii); compile as: g++ -O2 -fsanitize=address -Werror=maybe-uninitialized test.ii The following issue prevents bootstrapping GCC with --with-build-config=bootstrap-asan: gcc/explow.c:83:7: error: y may be used uninitialized in this function The reduced test case compiles warning free without ASAN, but with ASAN one gets: $ g++ -O2 -fsanitize=address -Werror=maybe-uninitialized test12.ii test12.ii: In function ‘rtx_def* plus_constant(machine_mode, rtx, long int)’: test12.ii:22:7: error: ‘y’ may be used uninitialized in this function [-Werror=maybe-uninitialized] rtx y; ^ cc1plus: some warnings being treated as errors