https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94338
Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jsm28 at gcc dot gnu.org, | |rguenth at gcc dot gnu.org Version|lto |9.2.1 Keywords| |diagnostic --- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- I think the testcase is ill-formed and should be diagnosed in some form. IIRC there's some documented behavior (that's not implemented) that __aligned__ only increases alignment unless __packed__ is used. With __packed__ the testcase behaves as expected I think. Note __attribute__((__aligned__(4))) applies to 'A', not its type. Not sure if behavior changes if you use a typedef that is aligned to 4.