Fix #11732 FP autoVariables when reassigning argv (#5084)

Author: chrchr-github

lib/checkautovariables.cpp

@@ -55,10 +55,10 @@ static bool isPtrArg(const Token *tok)
     return (var && var->isArgument() && var->isPointer());
 }
 
-static bool isArrayArg(const Token *tok)
+static bool isArrayArg(const Token *tok, const Settings* settings)
 {
     const Variable *var = tok->variable();
-    return (var && var->isArgument() && var->isArray());
+    return (var && var->isArgument() && var->isArray() && !settings->library.isentrypoint(var->scope()->className));
 }
 
 static bool isArrayVar(const Token *tok)
@@ -266,7 +266,7 @@ void CheckAutoVariables::autoVariables()
                 }
                 tok = tok->tokAt(4);
             } else if (Token::Match(tok, "[;{}] %var% [") && Token::simpleMatch(tok->linkAt(2), "] =") &&
-                       (isPtrArg(tok->next()) || isArrayArg(tok->next())) && isAddressOfLocalVariable(tok->linkAt(2)->next()->astOperand2())) {
+                       (isPtrArg(tok->next()) || isArrayArg(tok->next(), mSettings)) && isAddressOfLocalVariable(tok->linkAt(2)->next()->astOperand2())) {
                 errorAutoVariableAssignment(tok->next(), false);
             }
             // Invalid pointer deallocation

test/testautovariables.cpp

@@ -68,6 +68,7 @@ class TestAutoVariables : public TestFixture {
         TEST_CASE(testautovar16); // ticket #8114
         TEST_CASE(testautovar_array1);
         TEST_CASE(testautovar_array2);
+        TEST_CASE(testautovar_array3);
         TEST_CASE(testautovar_normal); // "normal" token list that does not remove casts etc
         TEST_CASE(testautovar_ptrptr); // ticket #6956
         TEST_CASE(testautovar_return1);
@@ -517,6 +518,14 @@ class TestAutoVariables : public TestFixture {
         ASSERT_EQUALS("[test.cpp:6]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
     }
 
+    void testautovar_array3() {
+        check("int main(int argc, char* argv[]) {\n" // #11732
+              "    std::string a = \"abc\";\n"
+              "    argv[0] = &a[0];\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void testautovar_normal() {
         check("void f(XmDestinationCallbackStruct *ds)\n"
               "{\n"