[flang-commits] [flang] [flang] Disable new -Wused-undefined-variable warning by default (PR #174151)

[Peter Klausler via flang-commits]

https://github.com/klausler created https://github.com/llvm/llvm-project/pull/174151

The new warning about local variables that are used without possible being defined or initialized may be generating some false positives; disable it by default for now.

>From 490c74313a0b90a4b33619803184e6ee44bc4892 Mon Sep 17 00:00:00 2001
From: Peter Klausler <pklausler at nvidia.com>
Date: Thu, 1 Jan 2026 09:04:38 -0800
Subject: [PATCH] [flang] Disable new -Wused-undefined-variable warning by
 default

The new warning about local variables that are used without
possible being defined or initialized may be generating some false
positives; disable it by default for now.
---
 flang/lib/Support/Fortran-features.cpp | 1 -
 1 file changed, 1 deletion(-)

diff --git a/flang/lib/Support/Fortran-features.cpp b/flang/lib/Support/Fortran-features.cpp
index 7544306a2b3fc..356050f22b443 100644
--- a/flang/lib/Support/Fortran-features.cpp
+++ b/flang/lib/Support/Fortran-features.cpp
@@ -152,7 +152,6 @@ LanguageFeatureControl::LanguageFeatureControl() {
   // New warnings, on by default
   warnLanguage_.set(LanguageFeature::SavedLocalInSpecExpr);
   warnLanguage_.set(LanguageFeature::NullActualForAllocatable);
-  warnUsage_.set(UsageWarning::UsedUndefinedVariable);
   warnUsage_.set(UsageWarning::BadValueInDeadCode);
 }