Fix #13311 FP thisUseAfterFree with static instance pointer (danmar#7008)

Author: chrchr-github

lib/checkclass.cpp

@@ -3470,7 +3470,7 @@ bool CheckClass::checkThisUseAfterFreeRecursive(const Scope *classScope, const F
             tok = tok->tokAt(2);
         } else if (Token::Match(tok, "%var% . reset ( )") && selfPointer == tok->variable())
             freeToken = tok;
-        else if (Token::Match(tok->previous(), "!!. %name% (") && tok->function() && tok->function()->nestedIn == classScope) {
+        else if (Token::Match(tok->previous(), "!!. %name% (") && tok->function() && tok->function()->nestedIn == classScope && tok->function()->type == Function::eFunction) {
             if (isDestroyed) {
                 thisUseAfterFree(selfPointer->nameToken(), freeToken, tok);
                 return true;

test/testclass.cpp

@@ -8947,6 +8947,22 @@ class TestClass : public TestFixture {
                               "    done();\n"
                               "}");
         ASSERT_EQUALS("", errout_str());
+
+        checkThisUseAfterFree("class C {\n" // #13311
+                              "public:\n"
+                              "    static void init();\n"
+                              "private:\n"
+                              "    C();\n"
+                              "    static C* self;\n"
+                              "    bool use;\n"
+                              "};\n"
+                              "C::C() { use = true; }\n"
+                              "void C::init() {\n"
+                              "    if (self)\n"
+                              "        delete self;\n"
+                              "    self = new C();\n"
+                              "}");
+        ASSERT_EQUALS("", errout_str());
     }