Fix #11148 Regression: Parameter \'ptr\' can be declared as pointer to const (#4233)

Author: chrchr-github

lib/checkother.cpp

@@ -1556,6 +1556,8 @@ void CheckOther::checkConstPointer()
             deref = true;
         else if (Token::simpleMatch(parent, "[") && parent->astOperand1() == tok && tok != nameTok)
             deref = true;
+        else if (Token::Match(parent, "%op%") && Token::simpleMatch(parent->astParent(), "."))
+            deref = true;
         else if (astIsRangeBasedForDecl(tok))
             continue;
         if (deref) {
@@ -1577,7 +1579,7 @@ void CheckOther::checkConstPointer()
             } else if (Token::simpleMatch(gparent, "[") && gparent->astOperand2() == parent)
                 continue;
         } else {
-            if (Token::Match(parent, "%oror%|%comp%|&&|?|!"))
+            if (Token::Match(parent, "%oror%|%comp%|&&|?|!|-"))
                 continue;
             else if (Token::simpleMatch(parent, "(") && Token::Match(parent->astOperand1(), "if|while"))
                 continue;

test/testother.cpp

@@ -3250,6 +3250,13 @@ class TestOther : public TestFixture {
               "    **b = 0;\n"
               "}\n");
         ASSERT_EQUALS("", errout.str());
+
+        check("ptrdiff_t f(int *p0, int *p1) {\n" // #11148
+              "    return p0 - p1;\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:1]: (style) Parameter 'p0' can be declared as pointer to const\n"
+                      "[test.cpp:1]: (style) Parameter 'p1' can be declared as pointer to const\n",
+                      errout.str());
     }
 
     void switchRedundantAssignmentTest() {