From 9836e8d035f72003b4af070c0da73660b28b8d2e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fr=C3=A9d=C3=A9ric=20Simonis?= <simonisfrederic@gmail.com>
Date: Wed, 8 Jan 2025 23:40:58 +0000
Subject: [PATCH] Fix read of uninitialized threshold in SparseQR

---
 Eigen/src/SparseQR/SparseQR.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Eigen/src/SparseQR/SparseQR.h b/Eigen/src/SparseQR/SparseQR.h
index acb0c5ffc..4cc4ea141 100644
--- a/Eigen/src/SparseQR/SparseQR.h
+++ b/Eigen/src/SparseQR/SparseQR.h
@@ -365,7 +365,6 @@ void SparseQR<MatrixType, OrderingType>::factorize(const MatrixType& mat) {
   IndexVector Ridx(n), Qidx(m);  // Store temporarily the row indexes for the current column of R and Q
   Index nzcolR, nzcolQ;          // Number of nonzero for the current column of R and Q
   ScalarVector tval(m);          // The dense vector used to compute the current column
-  RealScalar pivotThreshold = m_threshold;
 
   m_R.setZero();
   m_Q.setZero();
@@ -401,11 +400,14 @@ void SparseQR<MatrixType, OrderingType>::factorize(const MatrixType& mat) {
    * Tim Davis, "Algorithm 915, SuiteSparseQR: Multifrontal Multithreaded Rank-Revealing
    * Sparse QR Factorization, ACM Trans. on Math. Soft. 38(1), 2011, Page 8:3
    */
+  RealScalar pivotThreshold;
   if (m_useDefaultThreshold) {
     RealScalar max2Norm = 0.0;
     for (int j = 0; j < n; j++) max2Norm = numext::maxi(max2Norm, m_pmat.col(j).norm());
     if (max2Norm == RealScalar(0)) max2Norm = RealScalar(1);
     pivotThreshold = 20 * (m + n) * max2Norm * NumTraits<RealScalar>::epsilon();
+  } else {
+    pivotThreshold = m_threshold;
   }
 
   // Initialize the numerical permutation