https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65334
--- Comment #3 from Jan Hubicka <hubicka at ucw dot cz> --- This is patch I am testing. It turns out that vectorizer does update of alignment twice and both are wrong in aliases in different ways. In increase_alignment it decides to bump up alignment of alias target that is unsafe because target may be interposable while alias is not. Bumping up DECL_ALIGN will make us to produce invalid aligned accesses to the interposable references. In vectorizer itself it updates only DECL_ALIGN of alias and ignore the fact that target definition needs to be aligned. This patch moves the heavy lifting into symbol table and adds extra abstraction around alignments. Honza
