Fix #11820 FP duplicateExpression with double negation

chrchr-github · Jul 7, 2023 · c6e4158 · c6e4158
1 parent d6d3c7b
commit c6e4158
Show file tree

Hide file tree

Showing 2 changed files with 11 additions and 2 deletions.
diff --git a/lib/astutils.cpp b/lib/astutils.cpp
@@ -1458,10 +1458,10 @@ bool isSameExpression(bool cpp, bool macro, const Token *tok1, const Token *tok2
             tok2 = tok2->astOperand2();
     }
     // Skip double not
-    if (Token::simpleMatch(tok1, "!") && Token::simpleMatch(tok1->astOperand1(), "!") && !Token::simpleMatch(tok1->astParent(), "=")) {
+    if (Token::simpleMatch(tok1, "!") && Token::simpleMatch(tok1->astOperand1(), "!") && !Token::simpleMatch(tok1->astParent(), "=") && astIsBoolLike(tok2)) {
         return isSameExpression(cpp, macro, tok1->astOperand1()->astOperand1(), tok2, library, pure, followVar, errors);
     }
-    if (Token::simpleMatch(tok2, "!") && Token::simpleMatch(tok2->astOperand1(), "!") && !Token::simpleMatch(tok2->astParent(), "=")) {
+    if (Token::simpleMatch(tok2, "!") && Token::simpleMatch(tok2->astOperand1(), "!") && !Token::simpleMatch(tok2->astParent(), "=") && astIsBoolLike(tok1)) {
         return isSameExpression(cpp, macro, tok1, tok2->astOperand1()->astOperand1(), library, pure, followVar, errors);
     }
     const bool tok_str_eq = tok1->str() == tok2->str();

diff --git a/test/testother.cpp b/test/testother.cpp
@@ -6570,6 +6570,15 @@ class TestOther : public TestFixture {
               "    }\n"
               "}\n");
         ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (style) The comparison 'p == 0' is always true.\n", errout.str());
+
+        // #11820
+        check("unsigned f(unsigned x) {\n"
+              "    return x - !!x;\n"
+              "}\n"
+              "unsigned g(unsigned x) {\n"
+              "    return !!x - x;\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void duplicateExpression8() {