Fix #11037 FP knownConditionTrueFalse with dynamic_cast (#4297)

Author: chrchr-github

lib/valueflow.cpp

@@ -800,8 +800,7 @@ static void setTokenValue(Token* tok,
 
     // cast..
     if (const Token *castType = getCastTypeStartToken(parent)) {
-        if (((tok->valueType() == nullptr && value.isImpossible()) || astIsPointer(tok)) &&
-            contains({ValueFlow::Value::ValueType::INT, ValueFlow::Value::ValueType::SYMBOLIC}, value.valueType) &&
+        if (contains({ValueFlow::Value::ValueType::INT, ValueFlow::Value::ValueType::SYMBOLIC}, value.valueType) &&
             Token::simpleMatch(parent->astOperand1(), "dynamic_cast"))
             return;
         const ValueType &valueType = ValueType::parseDecl(castType, settings);

test/testcondition.cpp

@@ -667,6 +667,17 @@ class TestCondition : public TestFixture {
               "}");
         ASSERT_EQUALS("", errout.str());
 
+        check("class B { virtual void v() {} };\n" // #11037
+              "class D1 : public B {};\n"
+              "class D2 : public B {};\n"
+              "void f(const std::shared_ptr<B>&p) {\n"
+              "    const auto d1 = dynamic_cast<D1*>(p.get());\n"
+              "    const auto d2 = dynamic_cast<D2*>(p.get());\n"
+              "    if (d1) {}\n"
+              "    else if (d2) {}\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
+
         check("void f(int x) {\n" // #6482
               "  if (x & 1) {}\n"
               "  else if (x == 0) {}\n"