Test to ensure the function does not have an unresolved or unevaluated exception specification before testing whether the function throws or not. Fixes PR25574.

llvm-svn: 253598

clang-tools-extra/clang-tidy/cert/ThrownExceptionTypeCheck.cpp

@@ -19,9 +19,12 @@ AST_MATCHER(CXXConstructorDecl, isNoThrowCopyConstructor) {
   if (!Node.isCopyConstructor())
     return false;
 
-  if (const auto *FnTy = Node.getType()->getAs<FunctionProtoType>())
+  const auto *FnTy = Node.getType()->getAs<FunctionProtoType>();
+  // Assume the best for any unresolved exception specification.
+  if (isUnresolvedExceptionSpec(FnTy->getExceptionSpecType()))
+    return true;
+
   return FnTy->isNothrow(Node.getASTContext());
-  llvm_unreachable("Copy constructor with no prototype");
 }
 } // end namespace
 
@@ -36,7 +39,6 @@ void ThrownExceptionTypeCheck::registerMatchers(MatchFinder *Finder) {
               isCopyConstructor(), unless(isNoThrowCopyConstructor()))))
           .bind("expr"))),
       this);
-
 }
 
 void ThrownExceptionTypeCheck::check(const MatchFinder::MatchResult &Result) {

clang-tools-extra/test/clang-tidy/cert-throw-exception-type.cpp

@@ -108,5 +108,20 @@ void f() {
   throw Allocates(); // match, copy constructor throws
   // CHECK-MESSAGES: :[[@LINE-1]]:9: warning: thrown exception type is not nothrow copy constructible
   throw OptionallyAllocates(); // ok
-
+}
+
+namespace PR25574 {
+struct B {
+  B(const B&) noexcept;
+};
+
+struct D : B {
+  D();
+  virtual ~D() noexcept;
+};
+
+template <typename T>
+void f() {
+  throw D();
+}
 }