[clang-tools-extra] [clang-tidy] Fix trailing semicolon and lost comment in readability-use-std-min-max (PR #208782)

[via cfe-commits]

https://github.com/xxxxbc updated https://github.com/llvm/llvm-project/pull/208782

>From b0217e26f8a4ddbbefe50e86e4c3fbf7e5517e7b Mon Sep 17 00:00:00 2001
From: hehuan <2128534713 at qq.com>
Date: Sat, 11 Jul 2026 01:11:39 +0800
Subject: [PATCH] [clang-tidy] Fix trailing semicolon and lost comment in
 readability-use-std-min-max

For non-compound if bodies (no braces), If->getEndLoc() returns the end
of the expression, not the trailing semicolon. The replacement range
therefore stopped before the semicolon, causing a duplicate semicolon in
the output. Any comments between the expression and the semicolon were
also lost.

Add handling for the non-compound case that mirrors the existing
compound-statement logic: find the trailing semicolon, capture any
intervening comments, and extend the replacement range to cover it.

Fixes #208708.
---
 .../clang-tidy/readability/UseStdMinMaxCheck.cpp     | 10 +++++++++-
 clang-tools-extra/docs/ReleaseNotes.rst              |  4 ++++
 .../checkers/readability/use-std-min-max.cpp         | 12 ++++++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp b/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp
index ed1af05d232ce..b1a4001e293a6 100644
--- a/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp
+++ b/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp
@@ -167,7 +167,7 @@ void UseStdMinMaxCheck::check(const MatchFinder::MatchResult &Result) {
   const auto *BinaryOp = Result.Nodes.getNodeAs<BinaryOperator>("binaryOp");
   const BinaryOperatorKind BinaryOpcode = BinaryOp->getOpcode();
   const SourceLocation IfLocation = If->getIfLoc();
-  const SourceLocation ThenLocation = If->getEndLoc();
+  SourceLocation ThenLocation = If->getEndLoc();
 
   auto ReplaceAndDiagnose = [&](const StringRef FunctionName) {
     const SourceManager &Source = *Result.SourceManager;
@@ -218,6 +218,14 @@ void UseStdMinMaxCheck::check(const MatchFinder::MatchResult &Result) {
       if (Semi != StringRef::npos && PostInner.take_front(Semi).trim().empty())
         PostInner = PostInner.drop_front(Semi + 1);
       AppendNormalized(PostInner);
+    } else {
+      if (const auto SemiTok =
+              Lexer::findNextToken(ThenLocation, Source, LO);
+          SemiTok && SemiTok->is(tok::semi)) {
+        AppendNormalized(
+            GetSourceText(ThenLocation, SemiTok->getLocation()).rtrim());
+        ThenLocation = SemiTok->getLocation();
+      }
     }
 
     diag(IfLocation, "use `%0` instead of `%1`")
diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 9a5a23f3d8542..66ce08534cae8 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -121,6 +121,10 @@ Changes in existing checks
   exclusively for overload resolution. Added the :option:`IgnoredTypes`
   option to allow customizing the set of ignored types.
 
+- Improved :doc:`readability-use-std-min-max
+  <clang-tidy/checks/readability/use-std-min-max>` check by fixing spurious
+  trailing semicolons and lost comments when the ``if`` body has no braces.
+
 Removed checks
 ^^^^^^^^^^^^^^
 
diff --git a/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp b/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp
index 35570189e1122..ebc3783e84650 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp
@@ -253,6 +253,18 @@ void testVectorSizeType() {
     value = v.size();
 }
 
+namespace gh208708 {
+void f(int &n) {
+  // CHECK-MESSAGES: :[[@LINE+2]]:3: warning: use `std::max` instead of `<`
+  // CHECK-FIXES: n = std::max(n, -1);
+  if (n < -1) n = -1 ;
+
+  // CHECK-MESSAGES: :[[@LINE+2]]:3: warning: use `std::min` instead of `>`
+  // CHECK-FIXES: n = std::min(n, 1); /*use clamp when c++17 or later is enabled*/
+  if (n > 1) n = 1/*use clamp when c++17 or later is enabled*/;
+}
+} // namespace gh208708
+
 namespace gh121676 {
 
 void useLeft() {