From 81044ec13df7608d0d9d86aff2ef9805fc69bed1 Mon Sep 17 00:00:00 2001
From: Charles Schlosser <cs.schlosser@gmail.com>
Date: Thu, 19 Jun 2025 04:23:35 +0000
Subject: [PATCH] Provide macro to explicitly disable alloca

---
 Eigen/src/Core/util/Memory.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Eigen/src/Core/util/Memory.h b/Eigen/src/Core/util/Memory.h
index 5a2f07cf0..44056b334 100644
--- a/Eigen/src/Core/util/Memory.h
+++ b/Eigen/src/Core/util/Memory.h
@@ -762,7 +762,7 @@ void swap(scoped_array<T>& a, scoped_array<T>& b) {
  * This is accomplished through alloca if this later is supported and if the required number of bytes
  * is below EIGEN_STACK_ALLOCATION_LIMIT.
  */
-#ifdef EIGEN_ALLOCA
+#if defined(EIGEN_ALLOCA) && !defined(EIGEN_NO_ALLOCA)
 
 #if EIGEN_DEFAULT_ALIGN_BYTES > 0
 // We always manually re-align the result of EIGEN_ALLOCA.