On Wed, 2 Mar 2011, Richard Guenther wrote: > 2011-03-02 Richard Guenther <rguent...@suse.de> > > PR c/47939 > * c-decl.c (grokdeclarator): Drop to the main variant only > for array types. Drop flag_gen_aux_info check.
I can't convince myself that this is safe - that is, that it will maintain the invariant that TYPE_MAIN_VARIANT for an array type always points to a version where the ultimate element type is unqualified. The problem would be where the type from the declaration specifiers is a qualified type, not an array type, but becomes an array element type through array declarators being processed by grokdeclarator, and so arrays are built up directly with qualified element type without the unqualified variants being built first to become the main variants. It certainly appears that in a case such as typedef const int T; T a[10]; const int b[10]; you get multiple copies of the const int[10] type, some of which have a const int[10] variant as their main variant (incorrect) and some of which have an int[10] variant as their main variant (correct); the canonical types look rather odd as well. It's reasonable have multiple copies here - for the type T[10] to remember the type name T it was derived from - but in such a case they should still all be on the variant chain for a single int[10] main variant. -- Joseph S. Myers jos...@codesourcery.com
