Fix 13755: false negative: accessMoved with usage through dereference (danmar#7448)

Author: pfultz2

lib/vf_analyzers.cpp

@@ -47,6 +47,17 @@
 #include <set>
 #include <type_traits>
 
+static bool isDereferenceOp(const Token* tok)
+{
+    if (!tok)
+        return false;
+    if (!tok->astOperand1())
+        return false;
+    if (tok->str() == "*")
+        return true;
+    return tok->str() == "." && tok->originalName() == "->";
+}
+
 struct ValueFlowAnalyzer : Analyzer {
     const Settings& settings;
     ProgramMemoryState pms;
@@ -586,7 +597,7 @@ struct ValueFlowAnalyzer : Analyzer {
             } else {
                 return analyzeMatch(tok, d) | Action::Match;
             }
-        } else if (ref->isUnaryOp("*") && !match(ref->astOperand1())) {
+        } else if (isDereferenceOp(ref) && !match(ref->astOperand1())) {
             const Token* lifeTok = nullptr;
             for (const ValueFlow::Value& v:ref->astOperand1()->values()) {
                 if (!v.isLocalLifetimeValue())

test/testother.cpp

@@ -277,6 +277,7 @@ class TestOther : public TestFixture {
         TEST_CASE(moveAndReference);
         TEST_CASE(moveForRange);
         TEST_CASE(moveTernary);
+        TEST_CASE(movePointerAlias);
 
         TEST_CASE(funcArgNamesDifferent);
         TEST_CASE(funcArgOrderDifferent);
@@ -12111,6 +12112,17 @@ class TestOther : public TestFixture {
         ASSERT_EQUALS("", errout_str());
     }
 
+    void movePointerAlias()
+    {
+        check("void f() {\n"
+              "    std::string s;\n"
+              "    std::string s1 = std::move(s);\n"
+              "    const std::string* s_p = &s;\n"
+              "    s_p->size();\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:5]: (warning) Access of moved variable '.'.\n", errout_str());
+    }
+
     void funcArgNamesDifferent() {
         check("void func1(int a, int b, int c);\n"
               "void func1(int a, int b, int c) { }\n"

test/testuninitvar.cpp

@@ -6161,7 +6161,7 @@ class TestUninitVar : public TestFixture {
                         "    A* p = &a;\n"
                         "    g(p->x);\n"
                         "}\n");
-        ASSERT_EQUALS("[test.cpp:7] -> [test.cpp:8]: (error) Uninitialized variable: p->x\n", errout_str());
+        ASSERT_EQUALS("[test.cpp:8]: (error) Uninitialized variable: p->x\n", errout_str());
 
         valueFlowUninit("void f() {\n"
                         "    int a;\n"