Revert "Reland "[CMake] Bumps minimum version to 3.20.0.""
Unfortunatly not all buildbots are updated.
This reverts commit ffb807ab5375b3f78df198dc5d4302b3b552242f.
GitOrigin-RevId: e8e8707b4aa6e4cc04c0cffb2de01d2de71165fc
diff --git a/CMakeLists.txt b/CMakeLists.txt
index d91d1b1..c9b0d53 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
# MLIR project.
-cmake_minimum_required(VERSION 3.20.0)
+cmake_minimum_required(VERSION 3.13.4)
if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
@@ -11,6 +11,13 @@
if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
project(mlir)
set(MLIR_STANDALONE_BUILD TRUE)
+ if ("${CMAKE_VERSION}" VERSION_LESS "3.20.0")
+ message(WARNING
+ "Your CMake version is ${CMAKE_VERSION}. Starting with LLVM 17.0.0, the "
+ "minimum version of CMake required to build LLVM will become 3.20.0, and "
+ "using an older CMake will become an error. Please upgrade your CMake to "
+ "at least 3.20.0 now to avoid issues in the future!")
+ endif()
endif()
# Must go below project(..)
diff --git a/examples/standalone/CMakeLists.txt b/examples/standalone/CMakeLists.txt
index 038242b..65461c0 100644
--- a/examples/standalone/CMakeLists.txt
+++ b/examples/standalone/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.20.0)
+cmake_minimum_required(VERSION 3.13.4)
project(standalone-dialect LANGUAGES CXX C)
set(CMAKE_BUILD_WITH_INSTALL_NAME_DIR ON)
