https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115625
Bug ID: 115625 Summary: [10/11/13 Regression] misaligned address check missing 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 58509 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58509&action=edit Test file used in the report. OS: Ubuntu 22.04.3 LTS We found that gcc failed to catch misaligned address errors when compiling with gcc-13.2.0 at optimization level 1. $ ~/compiler-builds/gcc-13.2.0_build/bin/gcc -fsanitize=undefined -g -lgcc_s -I/home/csmith/include/csmith-2.3.0 -O1 testcase.c -o exec $ timeout 5s ./exec 2>exec.err $ cat exec.err $ ~/compiler-builds/gcc-14.1.0_build/bin/gcc -fsanitize=undefined -g -lgcc_s -I/home/csmith/include/csmith-2.3.0 -O1 testcase.c -o exec $ timeout 5s ./exec 2>exec.err $ cat exec.err testcase.c:25:7: runtime error: load of misaligned address 0x7ffe94ed505a for type 'int32_t', which requires 4 byte alignment 0x7ffe94ed505a: note: pointer points here 00 00 00 00 00 00 00 00 09 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 00 ^ $ We have found that gcc also fails to catch misaligned address errors in both gcc-11.4.0 at optimization level 1 and gcc-10.5.0 at optimization level 1.