[PATCH] make isScopedEnumerationType look through typedefs

[Stephan Bergmann]

> $ clang++ --version
> clang version 3.6.0 (trunk 219190)
> Target: x86_64-unknown-linux-gnu
> Thread model: posix
>
> $ cat test.cc
> enum class E { e };
> typedef E E2;
> E2 f1() { return E::e; }
> E f2() { return E::e; }
> bool g1() { return !f1(); }
> bool g2() { return !f2(); }
>
> $ clang++ -std=c++11 -c test.cc
> test.cc:6:20: error: invalid argument type 'E' to unary expression
> bool g2() { return !f2(); }
>                    ^~~~~
> 1 error generated.

rightly complains about the invalid contextual conversion to bool in g2 
but erroneously not also about the one in g1.

> Index: lib/Sema/SemaExpr.cpp
> ===================================================================
> --- lib/Sema/SemaExpr.cpp	(revision 219190)
> +++ lib/Sema/SemaExpr.cpp	(working copy)
> @@ -7414,7 +7414,7 @@
>  }
>
>  static bool isScopedEnumerationType(QualType T) {
> -  if (const EnumType *ET = dyn_cast<EnumType>(T))
> +  if (const EnumType *ET = dyn_cast<EnumType>(T.getCanonicalType()))
>      return ET->getDecl()->isScoped();
>    return false;
>  }

would fix that for me.

Stephan