From 7e929f864b6ded3c97bb701f72c0d3541b8f49b8 Mon Sep 17 00:00:00 2001
From: chrchr-github <noreply@github.com>
Date: Wed, 17 Jun 2026 21:42:45 +0200
Subject: [PATCH 1/3] Fix  #14848 FP compareValueOutOfTypeRangeError and
 knownConditionTrueFalse with unsigned arithmetic

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

diff --git a/lib/vf_settokenvalue.cpp b/lib/vf_settokenvalue.cpp
index fe94225083b..315f4a40129 100644
--- a/lib/vf_settokenvalue.cpp
+++ b/lib/vf_settokenvalue.cpp
@@ -613,7 +613,7 @@ namespace ValueFlow
         }
 
         // unary minus
-        else if (parent->isUnaryOp("-")) {
+        else if (parent->isUnaryOp("-") && !astIsUnsigned(parent)) {
             for (const Value &val : tok->values()) {
                 if (!val.isIntValue() && !val.isFloatValue())
                     continue;
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 0c8addb3b94..84396ac14e1 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -1261,6 +1261,12 @@ class TestValueFlow : public TestFixture {
         ASSERT_EQUALS(1U, values.size());
         ASSERT_EQUALS(-10, values.back().intvalue);
 
+        code = "bool f(unsigned a) {\n"
+               "    bool x = -a < 1;\n"
+               "    return x;\n"
+              "}";
+        ASSERT_EQUALS(false, testValueOfXKnown(code, 3U, 1));
+
         // Logical and
         code = "void f(bool b) {\n"
                "   bool x = false && b;\n"

From 4607f96bec834e03d8e6337c4b5f16095492e5a5 Mon Sep 17 00:00:00 2001
From: chrchr-github <noreply@github.com>
Date: Wed, 17 Jun 2026 21:49:36 +0200
Subject: [PATCH 2/3] Format

---
 test/testvalueflow.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 84396ac14e1..e5dc1a6e96c 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -1264,7 +1264,7 @@ class TestValueFlow : public TestFixture {
         code = "bool f(unsigned a) {\n"
                "    bool x = -a < 1;\n"
                "    return x;\n"
-              "}";
+               "}";
         ASSERT_EQUALS(false, testValueOfXKnown(code, 3U, 1));
 
         // Logical and

From 79b2132729def2339aa08e90f0940141542a8118 Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Thu, 18 Jun 2026 07:19:13 +0200
Subject: [PATCH 3/3] Update testvalueflow.cpp [skip ci]

---
 test/testvalueflow.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index e5dc1a6e96c..6a1ebe9d95e 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -1261,7 +1261,7 @@ class TestValueFlow : public TestFixture {
         ASSERT_EQUALS(1U, values.size());
         ASSERT_EQUALS(-10, values.back().intvalue);
 
-        code = "bool f(unsigned a) {\n"
+        code = "bool f(unsigned a) {\n" // #14848
                "    bool x = -a < 1;\n"
                "    return x;\n"
                "}";