Sema: Correctly build pointer-to-member arguments from a template argument with an IndirectFieldDecl

We only considered FieldDecl and CXXMethodDecl as appropriate which
would cause us to believe the IndirectFieldDecl corresponded to an
argument of it's field type instead of a pointer-to-member type.

This fixes PR17696.

llvm-svn: 193461

clang/lib/Sema/SemaTemplate.cpp

@@ -5075,7 +5075,8 @@ Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg,
   ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl());
 
   if (VD->getDeclContext()->isRecord() &&
-      (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) {
+      (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD) ||
+       isa<IndirectFieldDecl>(VD))) {
     // If the value is a class member, we might have a pointer-to-member.
     // Determine whether the non-type template template parameter is of
     // pointer-to-member type. If so, we need to build an appropriate

clang/test/SemaTemplate/temp_arg_nontype.cpp

@@ -350,3 +350,17 @@ namespace rdar13806270 {
   };
   void foo() {}
 }
+
+namespace PR17696 {
+  struct a {
+    union {
+      int i;
+    };
+  };
+
+  template <int (a::*p)> struct b : a {
+    b() { this->*p = 0; }
+  };
+
+  b<&a::i> c; // okay
+}