https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64078 --- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> --- I also saw FAIL: c-c++-common/ubsan/object-size-10.c -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects execution test at random on Linux/ia32.