https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86344
--- Comment #4 from Oliver Ddin <oddin at mimecast dot com> --- So, I grabbed GCC8.1.1 from trunk and built it. Crash reoccured. However, I noticed that GCC wasn't doing LTO through the linker plugin, so after rebuilding with the correct configuration to enable -fuse-linker-plugin to work, I then rebuilt the project and this time, LTO succeeded without error. So, I suspect this is specifically a bug that manifests when doing LTO without using the linker plugin. I unfortunately don't have anything better for you at this point and since I now have a working build, I'll probably not get the time to find a minimal case that reproduces this in the non-linker-plugin scenario.