Minor changes to function definition

Add templated test case

Author: snarang181

clang/include/clang/Sema/Sema.h

@@ -834,7 +834,7 @@ enum class CCEKind {
                            ///< message.
 };
 
-void inferNoReturnAttr(Sema &S, FunctionDecl *FD);
+void inferNoReturnAttr(Sema &S, const Decl *D);
 
 /// Sema - This implements semantic analysis and AST building for C.
 /// \nosubgrouping

clang/lib/Sema/Sema.cpp

@@ -2435,9 +2435,7 @@ Sema::PopFunctionScopeInfo(const AnalysisBasedWarnings::Policy *WP,
 
   // Issue any analysis-based warnings.
   if (WP && D) {
-    if (auto *FD = dyn_cast<FunctionDecl>(D)) {
-      inferNoReturnAttr(*this, const_cast<FunctionDecl *>(FD));
-    }
+    inferNoReturnAttr(*this, D);
     AnalysisWarnings.IssueWarnings(*WP, Scope.get(), D, BlockType);
   } else
     for (const auto &PUD : Scope->PossiblyUnreachableDiags)

clang/lib/Sema/SemaDeclAttr.cpp

@@ -1965,15 +1965,20 @@ static bool isKnownToAlwaysThrow(const FunctionDecl *FD) {
   return isa<CXXThrowExpr>(OnlyStmt);
 }
 
-void clang::inferNoReturnAttr(Sema &S, FunctionDecl *FD) {
+void clang::inferNoReturnAttr(Sema &S, const Decl *D) {
+  auto *FD = dyn_cast<FunctionDecl>(D);
+  if (!FD)
+    return;
+
+  auto *NonConstFD = const_cast<FunctionDecl *>(FD);
   DiagnosticsEngine &Diags = S.getDiagnostics();
   if (Diags.isIgnored(diag::warn_falloff_nonvoid, FD->getLocation()) &&
       Diags.isIgnored(diag::warn_suggest_noreturn_function, FD->getLocation()))
     return;
 
   if (!FD->hasAttr<NoReturnAttr>() && !FD->hasAttr<InferredNoReturnAttr>() &&
       isKnownToAlwaysThrow(FD)) {
-    FD->addAttr(InferredNoReturnAttr::CreateImplicit(S.Context));
+    NonConstFD->addAttr(InferredNoReturnAttr::CreateImplicit(S.Context));
   }
 }
 

clang/test/SemaCXX/wreturn-always-throws.cpp

@@ -12,6 +12,8 @@ namespace std {
   };
 }
 
+// Non-template version.
+
 void throwError(const std::string& msg) {
   throw std::runtime_error(msg);
 }
@@ -24,3 +26,21 @@ int ensureZero(const int i) {
 int alwaysThrows() {
   throw std::runtime_error("This function always throws"); // no-warning
 }
+
+// Template version.
+
+template<typename T> 
+void throwErrorTemplate(const T& msg) {
+  throw msg;
+}
+
+template <typename T>
+int ensureZeroTemplate(T i) {
+  if (i == 0) return 0;
+  throwErrorTemplate("ERROR"); // no-warning
+}
+
+void testTemplates() {
+  throwErrorTemplate("ERROR");
+  (void)ensureZeroTemplate(42);
+}