Fix #5678 FN destructor with no definition hide mismatching alloc/dealloc (#4401)

* Fix #5678 FN destructor with no definition hide mismatching allocation / deallocation

* Format

* Fix test

* Format

Author: chrchr-github

lib/checkmemoryleak.cpp

@@ -632,14 +632,14 @@ void CheckMemoryLeakInClass::variable(const Scope *scope, const Token *tokVarnam
                     if (destructor)
                         deallocInDestructor = true;
 
-                    // several types of allocation/deallocation?
-                    if (memberDealloc != CheckMemoryLeak::No && memberDealloc != dealloc)
-                        dealloc = CheckMemoryLeak::Many;
-
                     if (dealloc != CheckMemoryLeak::Many && memberAlloc != CheckMemoryLeak::No && memberAlloc != Many && memberAlloc != dealloc) {
                         mismatchAllocDealloc({tok}, classname + "::" + varname);
                     }
 
+                    // several types of allocation/deallocation?
+                    if (memberDealloc != CheckMemoryLeak::No && memberDealloc != dealloc)
+                        dealloc = CheckMemoryLeak::Many;
+
                     memberDealloc = dealloc;
                 }
 

test/testmemleak.cpp

@@ -1571,6 +1571,18 @@ class TestMemleakInClass : public TestFixture {
               "    delete [] pkt_buffer;\n"
               "}");
         ASSERT_EQUALS("[test.cpp:14]: (error) Mismatching allocation and deallocation: A::pkt_buffer\n", errout.str());
+
+        check("struct S {\n" // 5678
+              "    ~S();\n"
+              "    void f();\n"
+              "    int* p;\n"
+              "};\n"
+              "void S::f() {\n"
+              "    p = new char[1];\n"
+              "    delete p;\n"
+              "    p = 0;\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:8]: (error) Mismatching allocation and deallocation: S::p\n", errout.str());
     }
 
     void mismatch2() { // #5659