Fix #11184 FN leakNoVarFunctionCall with assignment (#8567)

Author: chrchr-github

lib/checkmemoryleak.cpp

@@ -1016,10 +1016,8 @@ void CheckMemoryLeakNoVarImpl::checkForUnreleasedInputArgument(const Scope *scop
         const Token* tok2 = tok->next()->astParent();
         while (tok2 && (tok2->isCast() || Token::Match(tok2, "?|:")))
             tok2 = tok2->astParent();
-        if (Token::Match(tok2, "%assign%")) // TODO: check if function returns allocated resource
-            continue;
-        if (Token::simpleMatch(tok->astTop(), "return"))
-            continue;
+        const bool hasAssign = Token::Match(tok2, "%assign%");
+        const bool hasReturn = Token::simpleMatch(tok->astTop(), "return");
 
         const std::string& functionName = tok->str();
         if ((tok->isCpp() && functionName == "delete") ||
@@ -1031,6 +1029,12 @@ void CheckMemoryLeakNoVarImpl::checkForUnreleasedInputArgument(const Scope *scop
         if (!tok->isKeyword() && !tok->function() && !mSettings.library.isLeakIgnore(functionName))
             continue;
 
+        if ((hasAssign || hasReturn) && !tok->function()) {
+            const std::string& ret = mSettings->library.returnValueType(tok);
+            if (ret.empty() || endsWith(ret, "*"))
+                continue;
+        }
+
         const std::vector<const Token *> args = getArguments(tok);
         int argnr = -1;
         for (const Token* arg : args) {

test/testmemleak.cpp

@@ -2602,6 +2602,17 @@ class TestMemleakNoVar : public TestFixture {
               "    a.g(new int);\n"
               "}\n");
         ASSERT_EQUALS("", errout_str());
+
+        check("int f() {\n" // #11184
+              "    return strlen(new char[4]{});\n"
+              "}\n"
+              "int g() {\n"
+              "    int i = strlen(new char[4]{});\n"
+              "    return i;\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:2:19]: (error) Allocation with new, strlen doesn't release it. [leakNoVarFunctionCall]\n"
+                      "[test.cpp:5:20]: (error) Allocation with new, strlen doesn't release it. [leakNoVarFunctionCall]\n",
+                      errout_str());
     }
 
     void missingAssignment() {