diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index 7bada82d6..704819bec 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -276,7 +276,7 @@ static void valueFlowBeforeCondition(TokenList *tokenlist, ErrorLogger *errorLog
                 // if variable is assigned in loop don't look before the loop
                 if (tok2->previous() &&
                     (Token::Match(tok2->previous(), "do") ||
-                     (tok2->str() == ")" && Token::Match(tok2->linkAt(-1)->previous(), "for|while (")))) {
+                     (tok2->strAt(-1) == ")" && Token::Match(tok2->linkAt(-1)->previous(), "for|while (")))) {
 
                     const Token *start = tok2;
                     const Token *end   = start->link();
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 4d95257bd..99f938d96 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -240,6 +240,15 @@ private:
                "    } while (1);\n"
                "}";
         ASSERT_EQUALS(false, testValueOfX(code, 2U, 76));
+
+        code = "void f(X x) {\n"  // conditions inside loop, x is assigned inside do-while => dont use condition
+               "    a = x;\n"
+               "    for (i=1;i<=count;i++) {\n"
+               "        BUGON(x==0)\n"
+               "        x = x.next;\n"
+               "    }\n"
+               "}";
+        ASSERT_EQUALS(false, testValueOfX(code, 2U, 0));
     }
 
     void valueFlowBeforeConditionTernaryOp() { // bailout: ?: