Fix issue 9275: False positive: Non-local object uses local variable (#2084)

lib/checkautovariables.cpp

@@ -595,6 +595,8 @@ void CheckAutoVariables::checkVarLifetimeScope(const Token * start, const Token
                 } else if (tok->variable() && tok->variable()->declarationId() == tok->varId()) {
                     var = tok->variable();
                 }
+                if (!isLifetimeBorrowed(tok, mSettings))
+                    continue;
                 if (var && !var->isLocal() && !var->isArgument() && !isVariableChanged(tok->next(), tok->scope()->bodyEnd, var->declarationId(), var->isGlobal(), mSettings, mTokenizer->isCPP())) {
                     errorDanglngLifetime(tok2, &val);
                     break;

test/testautovariables.cpp

@@ -1912,6 +1912,18 @@ private:
               "    return nullptr;\n"
               "}\n");
         ASSERT_EQUALS("", errout.str());
+
+        // #9275
+        check("struct S {\n"
+              "   void f();\n"
+              "   std::string m;\n"
+              "}\n"
+              "void S::f() {\n"
+              "    char buf[1024];\n"
+              "    const char* msg = buf;\n"
+              "    m = msg;\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void danglingLifetimeFunction() {