https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83402
--- Comment #4 from Paul Clarke <pc at us dot ibm.com> --- Created attachment 43829 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43829&action=edit unhelpful testcase $ gcc --version gcc (GCC) 8.0.1 20180402 (experimental) Copyright (C) 2018 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ gcc -o 83402 83402.c -DNO_WARN_X86_INTRINSICS -Wall -O3 -mcpu=power8 $ gcc -o 83402 83402.c -DNO_WARN_X86_INTRINSICS -Wall -mcpu=power8 $
