Further tweak -Wurneachable-code and templates by allowing the warning to run on

explicit template specializations (which represent actual functions somebody wrote).

Along the way, refactor some other code which similarly cares about whether or
not they are looking at a template instantiation.

llvm-svn: 145547

1 files changed, 6 insertions, 14 deletions

diff --git a/clang/lib/Sema/AnalysisBasedWarnings.cpp b/clang/lib/Sema/AnalysisBasedWarnings.cpp
index 54a26b3253a..fc635fba2dd 100644
--- a/clang/lib/Sema/AnalysisBasedWarnings.cpp
+++ b/clang/lib/Sema/AnalysisBasedWarnings.cpp
@@ -241,19 +241,8 @@ struct CheckFallThroughDiagnostics {
     
     // Don't suggest that template instantiations be marked "noreturn"
     bool isTemplateInstantiation = false;
-    if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(Func)) {
-      switch (Function->getTemplateSpecializationKind()) {
-      case TSK_Undeclared:
-      case TSK_ExplicitSpecialization:
-        break;
-        
-      case TSK_ImplicitInstantiation:
-      case TSK_ExplicitInstantiationDeclaration:
-      case TSK_ExplicitInstantiationDefinition:
-        isTemplateInstantiation = true;
-        break;
-      }
-    }
+    if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(Func))
+      isTemplateInstantiation = Function->isTemplateInstantiation();
         
     if (!isVirtualMethod && !isTemplateInstantiation)
       D.diag_NeverFallThroughOrReturn =
@@ -919,7 +908,10 @@ AnalysisBasedWarnings::IssueWarnings(sema::AnalysisBasedWarnings::Policy P,
     // Different template instantiations can effectively change the control-flow
     // and it is very difficult to prove that a snippet of code in a template
     // is unreachable for all instantiations.
-    if (S.ActiveTemplateInstantiations.empty())
+    bool isTemplateInstantiation = false;
+    if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(D))
+      isTemplateInstantiation = Function->isTemplateInstantiation();
+    if (!isTemplateInstantiation)
       CheckUnreachable(S, AC);
   }