https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69254
--- Comment #14 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Created attachment 37435 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=37435&action=edit gcc6-pr69254-wip.patch WIP patch. This handles the merging of the -fsanitize=/-fno-sanitize= options from the various TUs, except for the first TU (we don't call merge_and_complain for that, so right now it just passes through all the -fsanitize=/-fno-sanitize=, which is undesirable, it should do what merge_and_complain does with those options and remove the others). Perhaps merge_and_complain should be called in all cases, and for the first file be told by some bool arg it is the first one. But, before handling that, I see much bigger problem, and it is not only related to -fsanitize=, but to various other options. The thing is that the linker options are appended after the options derived from the TUs. If I say have a TU that has some OpenMP code in it and compile it with -c -flto -fopenmp, and then link with -flto or -flto -fopenmp, it works fine, but if I link with -flto -fno-openmp, I get very similar ICE to this PR. So clearly there are some options that should at least in some cases override even the linker options/
