From 5eee2dbda93146218a91c1aab20d6baf3507d531 Mon Sep 17 00:00:00 2001
From: Alexandru Savulescu <alexandru.savulescu@epfl.ch>
Date: Wed, 18 Aug 2021 13:57:42 +0200
Subject: [PATCH] Bump minimum supported CMake version to 3.15

---
 CMakeLists.txt | 13 +++----------
 README.md      |  2 +-
 2 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e02bdf9dd..6df9c0849 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,7 +3,7 @@
 #
 # See top-level LICENSE file for details.
 # =============================================================================
-cmake_minimum_required(VERSION 3.7 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.15 FATAL_ERROR)
 project(
   coreneuron
   VERSION 1.0
@@ -118,14 +118,11 @@ else()
 endif()
 
 if(CORENRN_ENABLE_GPU)
-  # Older CMake versions have not been tested for GPU/CUDA/OpenACC support after
+  # Older CMake versions than 3.15 have not been tested for GPU/CUDA/OpenACC support after
   # https://github.com/BlueBrain/CoreNeuron/pull/609.
   # https://cmake.org/cmake/help/latest/release/3.14.html#properties suggests there would be
   # problems because of expressions like set_target_properties(lfp_test_bin PROPERTIES
   # CUDA_RESOLVE_DEVICE_SYMBOLS OFF)
-  if(${CMAKE_VERSION} VERSION_LESS 3.15)
-    message(FATAL_ERROR "GPU support requires at least CMake v3.15!")
-  endif()
 
   # Fail hard and early if we don't have the PGI/NVHPC compiler.
   if(NOT CORENRN_HAVE_NVHPC_COMPILER)
@@ -466,11 +463,7 @@ message(STATUS "")
 message(STATUS "Configured CoreNEURON ${PROJECT_VERSION}")
 message(STATUS "")
 message(STATUS "You can now build CoreNEURON using:")
-if(${CMAKE_VERSION} VERSION_LESS "3.12")
-  message(STATUS "  cmake --build . [--target TARGET] -- -j 8")
-else()
-  message(STATUS "  cmake --build . --parallel 8 [--target TARGET]")
-endif()
+message(STATUS "  cmake --build . --parallel 8 [--target TARGET]")
 message(STATUS "You might want to adjust the number of parallel build jobs for your system.")
 message(STATUS "Some non-default targets you might want to build:")
 message(STATUS "--------------------+--------------------------------------------------------")
diff --git a/README.md b/README.md
index 7da6dd8f3..ed73e10ae 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,7 @@ CoreNEURON is designed as a library within the NEURON simulator and can transpar
 * POINTER variables need to be converted to BBCOREPOINTER ([details here](docs/userdoc/MemoryManagement/bbcorepointer.md))
 
 ## Dependencies
-* [CMake 3.7+](https://cmake.org)
+* [CMake 3.15+](https://cmake.org)
 * MPI Library [Optional, for MPI support]
 * [PGI OpenACC Compiler / NVIDIA HPC SDK](https://developer.nvidia.com/hpc-sdk) [Optional, for GPU support]
 * [CUDA Toolkit >=9.0](https://developer.nvidia.com/cuda-downloads) [Optional, for GPU support]