r285370 - Fix a crash on invalid code.

[Richard Trieu via cfe-commits]

Author: rtrieu
Date: Thu Oct 27 19:15:24 2016
New Revision: 285370

URL: http://llvm.org/viewvc/llvm-project?rev=285370&view=rev
Log:
Fix a crash on invalid code.

The diagnostic was attempting to access the QualType of a TypeDecl by calling
TypeDecl::getTypeForDecl.  However, the Type pointer stored there is lazily
loaded by functions in ASTContext.  In most cases, the pointer is loaded and
this does not cause a problem.  However, when more that 50 or so unknown types
are seen beforehand, this causes the Type to not be loaded, passing a null
Type to the diagnostics, leading to the crash.  Using
ASTContext::getTypeDeclType will give a proper QualType for all cases.

Modified:
    cfe/trunk/lib/Sema/SemaCXXScopeSpec.cpp
    cfe/trunk/test/SemaCXX/nested-name-spec.cpp

Modified: cfe/trunk/lib/Sema/SemaCXXScopeSpec.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaCXXScopeSpec.cpp?rev=285370&r1=285369&r2=285370&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaCXXScopeSpec.cpp (original)
+++ cfe/trunk/lib/Sema/SemaCXXScopeSpec.cpp Thu Oct 27 19:15:24 2016
@@ -801,7 +801,7 @@ bool Sema::BuildCXXNestedNameSpecifier(S
   if (!Found.empty()) {
     if (TypeDecl *TD = Found.getAsSingle<TypeDecl>())
       Diag(IdInfo.IdentifierLoc, diag::err_expected_class_or_namespace)
-          << QualType(TD->getTypeForDecl(), 0) << getLangOpts().CPlusPlus;
+          << Context.getTypeDeclType(TD) << getLangOpts().CPlusPlus;
     else {
       Diag(IdInfo.IdentifierLoc, diag::err_expected_class_or_namespace)
           << IdInfo.Identifier << getLangOpts().CPlusPlus;

Modified: cfe/trunk/test/SemaCXX/nested-name-spec.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/nested-name-spec.cpp?rev=285370&r1=285369&r2=285370&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/nested-name-spec.cpp (original)
+++ cfe/trunk/test/SemaCXX/nested-name-spec.cpp Thu Oct 27 19:15:24 2016
@@ -435,3 +435,21 @@ namespace PR16951 {
                              // expected-error{{no member named 'X2' in 'PR16951::enumerator_2'}}
 
 }
+
+namespace PR30619 {
+c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d;
+// expected-error at -1 16{{unknown type name 'c'}}
+c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d;
+// expected-error at -1 16{{unknown type name 'c'}}
+c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d;
+// expected-error at -1 16{{unknown type name 'c'}}
+c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d; c d;
+// expected-error at -1 16{{unknown type name 'c'}}
+namespace A {
+class B {
+  typedef C D; // expected-error{{unknown type name 'C'}}
+  A::D::F;
+  // expected-error at -1{{'D' (aka 'int') is not a class, namespace, or enumeration}}
+};
+}
+}