https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101949
--- Comment #13 from Richard Biener <rguenth at gcc dot gnu.org> --- When modref claims that bar doesn't write to 'fn' that confuses IPA PTA since internally it treats calling a function as "writing" to the argument space of all functions the function pointer points to. I'm not sure if it makes much sense to maintain any EAF_* flags when the argument is called, maybe we can drop to varying here in modref? For PTA it's really difficult since there may be data and functions in points-to sets so we can't easily "ignore" EAF_* flags for some arguments but not others. Also consider function pointers passed through a void * argument.
