Harmonize cmake_policy() across standalone builds of all projects

mgorny · mgorny · commit 9dd01a5241dc · 2022-10-28T08:46:48.000+02:00
Move `cmake_policy()` settings from `llvm/CMakeLists.txt` into a shared `cmake/modules/CMakePolicy.cmake`. Include it from all relevant projects that support standalone builds, in order to ensure that the policies are consistently set whether they are built in-tree or stand-alone. Differential Revision: https://reviews.llvm.org/D136572
diff --git a/clang/CMakeLists.txt b/clang/CMakeLists.txt
@@ -1,5 +1,11 @@
 cmake_minimum_required(VERSION 3.13.4)
 
+if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
+  set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
+endif()
+include(${LLVM_COMMON_CMAKE_UTILS}/Modules/CMakePolicy.cmake
+  NO_POLICY_SCOPE)
+
 # If we are not building as a part of LLVM, build Clang as an
 # standalone project, using LLVM as an external library:
 if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
@@ -136,10 +142,6 @@ if(CLANG_BUILT_STANDALONE)
   endif() # LLVM_INCLUDE_TESTS
 endif() # standalone
 
-if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
-  set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
-endif()
-
 # Make sure that our source directory is on the current cmake module path so that
 # we can include cmake files from this directory.
 list(INSERT CMAKE_MODULE_PATH 0
diff --git a/cmake/Modules/CMakePolicy.cmake b/cmake/Modules/CMakePolicy.cmake
@@ -0,0 +1,12 @@
+# CMake policy settings shared between LLVM projects
+
+# CMP0114: ExternalProject step targets fully adopt their steps.
+# New in CMake 3.19: https://cmake.org/cmake/help/latest/policy/CMP0114.html
+if(POLICY CMP0114)
+  cmake_policy(SET CMP0114 OLD)
+endif()
+# CMP0116: Ninja generators transform `DEPFILE`s from `add_custom_command()`
+# New in CMake 3.20. https://cmake.org/cmake/help/latest/policy/CMP0116.html
+if(POLICY CMP0116)
+  cmake_policy(SET CMP0116 OLD)
+endif()
diff --git a/flang/CMakeLists.txt b/flang/CMakeLists.txt
@@ -1,5 +1,11 @@
 cmake_minimum_required(VERSION 3.13.4)
 
+if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
+  set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
+endif()
+include(${LLVM_COMMON_CMAKE_UTILS}/Modules/CMakePolicy.cmake
+  NO_POLICY_SCOPE)
+
 set(CMAKE_BUILD_WITH_INSTALL_NAME_DIR ON)
 
 # Flang requires C++17.
@@ -233,10 +239,6 @@ include_directories(BEFORE
   ${FLANG_BINARY_DIR}/include
   ${FLANG_SOURCE_DIR}/include)
 
-if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
-  set(LLVM_COMMON_CMAKE_UTILS ${FLANG_SOURCE_DIR}/../cmake)
-endif()
-
 # Add Flang-centric modules to cmake path.
 list(INSERT CMAKE_MODULE_PATH 0
   "${FLANG_SOURCE_DIR}/cmake/modules"
diff --git a/lld/CMakeLists.txt b/lld/CMakeLists.txt
@@ -1,5 +1,11 @@
 cmake_minimum_required(VERSION 3.13.4)
 
+if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
+  set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
+endif()
+include(${LLVM_COMMON_CMAKE_UTILS}/Modules/CMakePolicy.cmake
+  NO_POLICY_SCOPE)
+
 # If we are not building as a part of LLVM, build LLD as an
 # standalone project, using LLVM as an external library:
 if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
@@ -140,10 +146,6 @@ if (CMAKE_SOURCE_DIR STREQUAL CMAKE_BINARY_DIR)
 "`CMakeFiles'. Please delete them.")
 endif()
 
-if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
-  set(LLVM_COMMON_CMAKE_UTILS ${LLD_SOURCE_DIR}/../cmake)
-endif()
-
 # Add path for custom modules.
 list(INSERT CMAKE_MODULE_PATH 0
   "${LLD_SOURCE_DIR}/cmake/modules"
diff --git a/lldb/CMakeLists.txt b/lldb/CMakeLists.txt
@@ -1,5 +1,11 @@
 cmake_minimum_required(VERSION 3.13.4)
 
+if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
+  set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
+endif()
+include(${LLVM_COMMON_CMAKE_UTILS}/Modules/CMakePolicy.cmake
+  NO_POLICY_SCOPE)
+
 # Add path for custom modules.
 set(CMAKE_MODULE_PATH
   ${CMAKE_MODULE_PATH}
diff --git a/lldb/cmake/modules/LLDBStandalone.cmake b/lldb/cmake/modules/LLDBStandalone.cmake
@@ -1,9 +1,3 @@
-# CMP0116: Ninja generators transform `DEPFILE`s from `add_custom_command()`
-# New in CMake 3.20. https://cmake.org/cmake/help/latest/policy/CMP0116.html
-if(POLICY CMP0116)
-  cmake_policy(SET CMP0116 OLD)
-endif()
-
 if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
   set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
 endif()
diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
@@ -2,16 +2,9 @@
 
 cmake_minimum_required(VERSION 3.13.4)
 
-# CMP0114: ExternalProject step targets fully adopt their steps.
-# New in CMake 3.19: https://cmake.org/cmake/help/latest/policy/CMP0114.html
-if(POLICY CMP0114)
-  cmake_policy(SET CMP0114 OLD)
-endif()
-# CMP0116: Ninja generators transform `DEPFILE`s from `add_custom_command()`
-# New in CMake 3.20. https://cmake.org/cmake/help/latest/policy/CMP0116.html
-if(POLICY CMP0116)
-  cmake_policy(SET CMP0116 OLD)
-endif()
+set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
+include(${LLVM_COMMON_CMAKE_UTILS}/Modules/CMakePolicy.cmake
+  NO_POLICY_SCOPE)
 
 set(CMAKE_BUILD_WITH_INSTALL_NAME_DIR ON)
 
@@ -281,8 +274,6 @@ if(LLVM_ENABLE_GISEL_COV)
   set(LLVM_GISEL_COV_PREFIX "${CMAKE_BINARY_DIR}/gisel-coverage-" CACHE STRING "Provide a filename prefix to collect the GlobalISel rule coverage")
 endif()
 
-set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
-
 # Add path for custom modules
 list(INSERT CMAKE_MODULE_PATH 0
   "${CMAKE_CURRENT_SOURCE_DIR}/cmake"
diff --git a/mlir/CMakeLists.txt b/mlir/CMakeLists.txt
@@ -1,4 +1,11 @@
 # MLIR project.
+cmake_minimum_required(VERSION 3.13.4)
+
+if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
+  set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
+endif()
+include(${LLVM_COMMON_CMAKE_UTILS}/Modules/CMakePolicy.cmake
+  NO_POLICY_SCOPE)
 
 # Check if MLIR is built as a standalone project.
 if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
@@ -10,8 +17,6 @@ endif()
 include(GNUInstallDirs)
 
 if(MLIR_STANDALONE_BUILD)
-  cmake_minimum_required(VERSION 3.13.4)
-
   find_package(LLVM CONFIG REQUIRED)
   set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${LLVM_CMAKE_DIR})
   include(HandleLLVMOptions)
@@ -46,10 +51,6 @@ set(MLIR_BINARY_DIR  ${CMAKE_CURRENT_BINARY_DIR})
 set(MLIR_INCLUDE_DIR ${CMAKE_CURRENT_BINARY_DIR}/include)
 set(MLIR_TOOLS_DIR   ${CMAKE_RUNTIME_OUTPUT_DIRECTORY})
 
-if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
-  set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
-endif()
-
 # Make sure that our source directory is on the current cmake module path so
 # that we can include cmake files from this directory.
 list(INSERT CMAKE_MODULE_PATH 0
