https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85921
--- Comment #3 from John Simon <gcc at mailinator dot com> --- The include chain is: # 415 "../../gcc-8.1.0/gcc/system.h" <-- "/usr/include/signal.h" <-- "/usr/include/bits/sigcontext.h" <-- "/usr/include/asm/sigcontext.h" <-- "/usr/include/linux/compiler.h"