Fix #11458 nullPointer false positive (#4758)

Author: chrchr-github

lib/symboldatabase.cpp

@@ -5470,10 +5470,14 @@ const Function* Scope::findFunction(const Token *tok, bool requireConst) const
     if (fallback2Func)
         return fallback2Func;
 
-    // remove pure virtual function
-    matches.erase(std::remove_if(matches.begin(), matches.end(), [](const Function* m) {
+    // remove pure virtual function if there is an overrider
+    auto itPure = std::find_if(matches.begin(), matches.end(), [](const Function* m) {
         return m->isPure();
-    }), matches.end());
+    });
+    if (itPure != matches.end() && std::any_of(matches.begin(), matches.end(), [&](const Function* m) {
+        return m->isImplicitlyVirtual() && m != *itPure;
+    }))
+        matches.erase(itPure);
 
     // Only one candidate left
     if (matches.size() == 1)

test/testnullpointer.cpp

@@ -141,6 +141,7 @@ class TestNullPointer : public TestFixture {
         TEST_CASE(nullpointer95); // #11142
         TEST_CASE(nullpointer96); // #11416
         TEST_CASE(nullpointer97); // #11229
+        TEST_CASE(nullpointer98); // #11458
         TEST_CASE(nullpointer_addressOf); // address of
         TEST_CASE(nullpointerSwitch); // #2626
         TEST_CASE(nullpointer_cast); // #4692
@@ -2796,6 +2797,17 @@ class TestNullPointer : public TestFixture {
         ASSERT_EQUALS("", errout.str());
     }
 
+    void nullpointer98() // #11458
+    {
+        check("struct S { double* d() const; };\n"
+              "struct T {\n"
+              "    virtual void g(double* b, double* d) const = 0;\n"
+              "    void g(S* b) const { g(b->d(), nullptr); }\n"
+              "    void g(S* b, S* d) const { g(b->d(), d->d()); }\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void nullpointer_addressOf() { // address of
         check("void f() {\n"
               "  struct X *x = 0;\n"