[PATCH] Delay lookup of simple default template arguments under -fms-compatibility

[David Majnemer]

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Comment at: lib/Parse/ParseDecl.cpp:2764
@@ +2763,3 @@
+          getCurScope()->isTemplateParamScope() &&
+          DSContext == DSC_template_type_arg) {
+        TypeRep = Actions.ActOnDelayedDefaultTemplateArg(
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Perhaps move the `DSContext == DSC_template_type_arg` check before the calls to `getLangOpts()` ? It should be a little cheaper.

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Comment at: lib/Sema/SemaDecl.cpp:358
@@ +357,3 @@
+    return NestedNameSpecifier::Create(Context, SubNNS, ND);
+  else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC))
+    return NestedNameSpecifier::Create(Context, SubNNS, RD->isTemplateDecl(),
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Perhaps `auto RD = dyn_cast<CXXRecordDecl(DC))` ?

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Comment at: lib/Sema/SemaDecl.cpp:366
@@ +365,3 @@
+                                                SourceLocation NameLoc) {
+  Diag(NameLoc, diag::ext_ms_delayed_template_argument) << &II;
+
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Perhaps a comment as to why we are emitting this diagnostic?

http://reviews.llvm.org/D3995