https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64442
--- Comment #1 from Mikael Pettersson <mikpelinux at gmail dot com> --- Are you compiling on 32-bit x86? I can reproduce on m68k, but not on x86_64 (even with -m32) or on ARMv5. I suspect you're seeing the effects of excess precision of the x87 FPU (much like the m68k FPU).