From f7ddd7a35da032a6377292d86aad699734188a02 Mon Sep 17 00:00:00 2001
From: Paul Fultz II <pfultz2@yahoo.com>
Date: Tue, 24 Aug 2021 21:51:54 -0500
Subject: [PATCH] Fix 10430: FP knownConditionTrueFalse with bool from unsigned
 char (#3416)

---
 lib/valueflow.cpp      | 13 +++++++------
 test/testvalueflow.cpp | 10 ++++++++++
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index 1d663c494..13d9520cb 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -4716,12 +4716,13 @@ static void valueFlowForwardAssign(Token* const tok,
     }
 
     if (tokenlist->isCPP() && vars.size() == 1 && Token::Match(vars.front()->typeStartToken(), "bool|_Bool")) {
-        std::list<ValueFlow::Value>::iterator it;
-        for (it = values.begin(); it != values.end(); ++it) {
-            if (it->isIntValue())
-                it->intvalue = (it->intvalue != 0);
-            if (it->isTokValue())
-                it->intvalue = (it->tokvalue != nullptr);
+        for (ValueFlow::Value& value : values) {
+            if (value.isImpossible())
+                continue;
+            if (value.isIntValue())
+                value.intvalue = (value.intvalue != 0);
+            if (value.isTokValue())
+                value.intvalue = (value.tokvalue != nullptr);
         }
     }
 
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 2348d7ecd..3a9cb9eed 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -2434,6 +2434,16 @@ private:
                "}\n";
         ASSERT_EQUALS(true, testValueOfX(code, 12U, 0));
         ASSERT_EQUALS(false, testValueOfXKnown(code, 12U, 0));
+
+        code = "bool f(unsigned char uc) {\n"
+               "  const bool x = uc;\n"
+               "  return x;\n"
+               "}\n";
+        ASSERT_EQUALS(true, testValueOfXImpossible(code, 3U, -1));
+        ASSERT_EQUALS(false, testValueOfXKnown(code, 3U, 1));
+        ASSERT_EQUALS(false, testValueOfXKnown(code, 3U, 0));
+        ASSERT_EQUALS(false, testValueOfXImpossible(code, 3U, 0));
+        ASSERT_EQUALS(false, testValueOfXImpossible(code, 3U, 1));
     }
 
     void valueFlowAfterCondition() {