fix #12238: FP memleak when passing buffer in vector (#7696)

Author: ludviggunne

lib/checkleakautovar.cpp

@@ -396,6 +396,16 @@ bool CheckLeakAutoVar::checkScope(const Token * const startToken,
             }
         }
 
+        if (tok->isCpp11init() == TokenImpl::Cpp11init::CPP11INIT) {
+            const Token *newTok = tok->astOperand1();
+            const Token *oldTok = tok->astOperand2();
+            if (newTok && newTok->varId() && oldTok && oldTok->varId()) {
+                leakIfAllocated(newTok, varInfo);
+                // no multivariable checking currently => bail out for rhs variables
+                varInfo.erase(oldTok->varId());
+            }
+        }
+
         auto isAssignment = [](const Token* varTok) -> const Token* {
             if (varTok->varId()) {
                 const Token* top = varTok;

test/testleakautovar.cpp

@@ -180,6 +180,7 @@ class TestLeakAutoVar : public TestFixture {
         TEST_CASE(return9);
         TEST_CASE(return10);
         TEST_CASE(return11); // #13098
+        TEST_CASE(return12); // #12238
 
         // General tests: variable type, allocation type, etc
         TEST_CASE(test1);
@@ -2832,6 +2833,17 @@ class TestLeakAutoVar : public TestFixture {
         ASSERT_EQUALS("[test.c:7:5]: (error) Memory leak: ptr [memleak]\n", errout_str());
     }
 
+    void return12() { // #12238
+        CheckOptions options;
+        options.cpp = true;
+        check("void f(size_t size) {\n"
+              "    void* buffer = malloc(size);\n"
+              "    std::vector<void*> v{ buffer };\n"
+              "    x->g(v);\n"
+              "}\n", options);
+        ASSERT_EQUALS("", errout_str());
+    }
+
     void test1() {
         check("void f(double*&p) {\n" // 3809
               "    p = malloc(0x100);\n"