https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116031
Bug ID: 116031 Summary: signed integer overflow check at optimization level -O3 Product: gcc Version: 13.2.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: sanitizer Assignee: unassigned at gcc dot gnu.org Reporter: bic60176 at gmail dot com 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 Target Milestone: --- Created attachment 58720 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58720&action=edit testcase OS: Ubuntu 22.04.3 LTS We found a case that UBSAN not reporting signed integer overflow when compiling with gcc-13.2.0 and gcc-14.1.0 at optimization level -O3. $ ../compiler-builds/gcc-13.2.0_build/bin/gcc -fsanitize=undefined -fsanitize=address -g -lgcc_s -O3 testcase.c -o exec $ timeout 1s ./exec 2>exec.err $ ../compiler-builds/gcc-12.3.0_build/bin/gcc -fsanitize=undefined -fsanitize=address -g -lgcc_s -O3 testcase.c -o exec $ timeout 1s ./exec 2>exec.err testcase.c:22:15: runtime error: signed integer overflow: 754946112 + 1912123656 cannot be represented in type 'int' I wonder if gcc-13 and gcc-14 have optimized out the part that cause signed integer overflow.