r187769 - Fix for PR16570: when comparing two function pointers, discard qualifiers when

[Eli Friedman]

On Mon, Aug 5, 2013 at 8:44 PM, Richard Trieu <rtrieu at google.com> wrote:
> Author: rtrieu
> Date: Mon Aug  5 22:44:10 2013
> New Revision: 187769
>
> URL: http://llvm.org/viewvc/llvm-project?rev=187769&view=rev
> Log:
> Fix for PR16570: when comparing two function pointers, discard qualifiers when
> comparing non-reference function parameters.  The qualifiers don't matter for
> comparisons.
>
> Added:
>     cfe/trunk/test/SemaCXX/function-pointer-arguments.cpp
> Modified:
>     cfe/trunk/lib/Sema/SemaOverload.cpp
>
> Modified: cfe/trunk/lib/Sema/SemaOverload.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaOverload.cpp?rev=187769&r1=187768&r2=187769&view=diff
> ==============================================================================
> --- cfe/trunk/lib/Sema/SemaOverload.cpp (original)
> +++ cfe/trunk/lib/Sema/SemaOverload.cpp Mon Aug  5 22:44:10 2013
> @@ -2584,9 +2584,17 @@ bool Sema::FunctionArgTypesAreEqual(cons
>    for (FunctionProtoType::arg_type_iterator O = OldType->arg_type_begin(),
>         N = NewType->arg_type_begin(),
>         E = OldType->arg_type_end(); O && (O != E); ++O, ++N) {
> -    if (!Context.hasSameType(*O, *N)) {
> -      if (ArgPos) *ArgPos = O - OldType->arg_type_begin();
> -      return false;
> +    if (!(*O)->isReferenceType() && !(*N)->isReferenceType()) {
> +      if (!Context.hasSameType(O->getUnqualifiedType(),
> +                               N->getUnqualifiedType())) {
> +        if (ArgPos) *ArgPos = O - OldType->arg_type_begin();
> +        return false;
> +      }
> +    } else {
> +      if (!Context.hasSameType(*O, *N)) {
> +        if (ArgPos) *ArgPos = O - OldType->arg_type_begin();
> +        return false;
> +      }

These two branches do the same thing because reference types are never
qualified.

-Eli