From 4b11bb4ad3d4f8becebdc5d553e24f92d94180b6 Mon Sep 17 00:00:00 2001
From: Paul Fultz II <pfultz2@yahoo.com>
Date: Tue, 18 May 2021 00:28:45 -0500
Subject: [PATCH] 10278: ValueFlow: Wrong known value, sign conversion (#3260)

---
 lib/valueflow.cpp      | 2 +-
 test/testcondition.cpp | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index 169df0b68..fd5585cdd 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -1461,7 +1461,7 @@ static std::vector<MathLib::bigint> minUnsignedValue(const Token* tok, int depth
         return result;
     if (tok->hasKnownIntValue()) {
         result = {tok->values().front().intvalue};
-    } else if (tok->isConstOp() && tok->astOperand1() && tok->astOperand2()) {
+    } else if (tok->str() != "-" && tok->isConstOp() && tok->astOperand1() && tok->astOperand2()) {
         std::vector<MathLib::bigint> op1 = minUnsignedValue(tok->astOperand1(), depth - 1);
         std::vector<MathLib::bigint> op2 = minUnsignedValue(tok->astOperand2(), depth - 1);
         if (!op1.empty() && !op2.empty()) {
diff --git a/test/testcondition.cpp b/test/testcondition.cpp
index c431fcf91..90f661ec1 100644
--- a/test/testcondition.cpp
+++ b/test/testcondition.cpp
@@ -3620,6 +3620,12 @@ private:
               "    g(name);\n"
               "}\n");
         ASSERT_EQUALS("[test.cpp:5]: (style) Condition 'name.empty()' is always true\n", errout.str());
+
+        // #10278
+        check("void foo(unsigned int x) {\n"
+              "    if ((100 - x) > 0) {}\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void alwaysTrueInfer() {