From b469da10699e17f129ccc3388b66de12c577ecf2 Mon Sep 17 00:00:00 2001
From: Paul Fultz II <pfultz2@yahoo.com>
Date: Wed, 13 Jan 2021 05:35:43 -0600
Subject: [PATCH] Fix issue 8253: False negative: Comparison is always true
 (early return) (#3043)

---
 lib/forwardanalyzer.cpp |  2 --
 test/testvalueflow.cpp  | 10 ++++++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/lib/forwardanalyzer.cpp b/lib/forwardanalyzer.cpp
index e48c8b733..8d52d2402 100644
--- a/lib/forwardanalyzer.cpp
+++ b/lib/forwardanalyzer.cpp
@@ -386,8 +386,6 @@ struct ForwardTraversal {
                 Token* endBlock = endCond->next()->link();
                 Token* condTok = getCondTok(tok);
                 Token* initTok = getInitTok(tok);
-                if (!condTok)
-                    return Progress::Break;
                 if (initTok && updateRecursive(initTok) == Progress::Break)
                     return Progress::Break;
                 if (Token::Match(tok, "for|while (")) {
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index eb2cf93fb..8a7ffd494 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -4270,6 +4270,16 @@ private:
                "}\n";
         ASSERT_EQUALS(false, testValueOfXKnown(code, 10U, 0));
         ASSERT_EQUALS(false, testValueOfXKnown(code, 10U, 1));
+
+        code = "void f() {\n"
+               "    const int size = arrayInfo.num(0);\n"
+               "    if (size <= 0)\n"
+               "        return;\n"
+               "    for (;;)\n"
+               "        if (size > 0) {}\n"
+               "}\n";
+        ASSERT_EQUALS(true, valueOfTok(code, "> 0").isKnown());
+        ASSERT_EQUALS(true, valueOfTok(code, "> 0").intvalue == 1);
     }
 
     static std::string isPossibleContainerSizeValue(const std::list<ValueFlow::Value> &values, MathLib::bigint i) {