https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85574
--- Comment #38 from Eric Botcazou <ebotcazou at gcc dot gnu.org> --- > Feel free to improve things - I do not have any Windows system to > test on or an idea what you think needs to be improved. I would > guess similar things apply to compare-debug which it was derived from. That's even more broken than initially thought: nobody sets $(exeext) at top level so gcc/lto1 is passed and then the behavior is random since some tools apppend the missing .exe implicitly and some don't.
