[Bug lto/61886] [4.8/4.9/5 Regression] LTO breaks fread with _FORTIFY_SOURCE=2

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61886

--- Comment #24 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
But is warning/error attribute the only thing on aliases that can hold extra
semantics info (now or in the future)?  I'd say LTO symtab merging should merge
what is mergeable, and should leave leave as separate decls with the same
asm-name what holds non-mergeable semantics on it.
Say, if you declare some function (or different, just with same asm name) with
warning attribute in one TU, with error attribute in another TU and without it
on another TU, IMHO those three decls shouldn't be merged together, you should
note in cgraph that you have aliases that have the same asm name but different
semantics and just ensure that you use the right cgraph nodes and decls in the
corresponding callers.