From 363d14189051e9f0d9948eb64d3b6fe17051bc34 Mon Sep 17 00:00:00 2001
From: Michael Hirsch <scivision@users.noreply.github.com>
Date: Mon, 27 Nov 2023 23:30:08 -0500
Subject: [PATCH] cmake >= 3.19

---
 cmake/lapack.cmake | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/cmake/lapack.cmake b/cmake/lapack.cmake
index 8f6f311..fa56e8a 100644
--- a/cmake/lapack.cmake
+++ b/cmake/lapack.cmake
@@ -1,6 +1,13 @@
 include(GNUInstallDirs)
 include(ExternalProject)
 
+if(CMAKE_VERSION VERSION_LESS 3.21)
+  get_property(not_top DIRECTORY PROPERTY PARENT_DIRECTORY)
+  if(NOT not_top)
+    set(PROJECT_IS_TOP_LEVEL true)
+  endif()
+endif()
+
 if(NOT PROJECT_IS_TOP_LEVEL)
   message(STATUS "${PROJECT_NAME} ${PROJECT_VERSION} deferring to ${CMAKE_PROJECT_NAME} for LAPACK")
   return()