https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105260
--- Comment #4 from m.cencora at gmail dot com --- I dont think ABI is an issue here. The Foo variable is spilled into stack, and then reloaded back into RDI register before invoking dummyFunc. Also clang generates optimal code as can be seen here: https://godbolt.org/z/K6jWY9h3b
