Fixed danmar#7135 (ValueFlow: Wrong pointer alias set for 'p = &p[x];')

danmar · danmar · commit 04ecbba361a4 · 2015-11-15T23:38:23.000+01:00
diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
@@ -703,7 +703,16 @@ static void valueFlowPointerAlias(TokenList *tokenlist)
             continue;
 
         // child should be some buffer or variable
-        if (!Token::Match(tok->astOperand1(), "%name%|.|[|;"))
+        const Token *vartok = tok->astOperand1();
+        while (vartok) {
+            if (vartok->str() == "[")
+                vartok = vartok->astOperand1();
+            else if (vartok->str() == "." || vartok->str() == "::")
+                vartok = vartok->astOperand2();
+            else
+                break;
+        }
+        if (!(vartok && vartok->variable() && !vartok->variable()->isPointer()))
             continue;
 
         ValueFlow::Value value;
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
@@ -209,6 +209,13 @@ class TestValueFlow : public TestFixture {
                 "  *x = 0;\n"  // <- x can point at i
                 "}";
         ASSERT_EQUALS(true, testValueOfX(code, 4, "& i"));
+
+        code  = "void f() {\n"
+                "  struct X *x;\n"
+                "  x = &x[1];\n"
+                "}";
+        ASSERT_EQUALS(true, tokenValues(code, "&").empty());
+        ASSERT_EQUALS(true, tokenValues(code, "x [").empty());
     }
 
     void valueFlowArrayElement() {
