Handle direct throws in functions.

Author: snarang181

clang/lib/Sema/AnalysisBasedWarnings.cpp

@@ -722,6 +722,10 @@ static void CheckFallThroughForBody(Sema &S, const Decl *D, const Stmt *Body,
                 }
               }
             }
+            // Direct throw.
+            if (isa<CXXThrowExpr>(LastStmt)) {
+              return; // Don't warn about fall-through.
+            }
           }
         }
       }

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

@@ -20,3 +20,7 @@ int ensureZero(const int i) {
   if (i == 0) return 0;
   throwError("ERROR"); // no-warning
 }
+
+int alwaysThrows() {
+  throw std::runtime_error("This function always throws"); // no-warning
+}