[CMake] Add warning for using compile and link pools on unsupported versions of CMake...

Summary: I've gotten feedback from users on CMake 2.8 that the compile and link pool options were not working. This is expected so I'm adding a warning so we can report invalid configurations to users.

Reviewers: eugenis

Reviewed By: eugenis

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10193

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239044 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 568376ee7005efdd629ee9daaa6b39082b629b0b..837148bb8d7b26f2931fb6806b4c8eb7b00d5a98 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -32,15 +32,23 @@ project(LLVM)
 set(LLVM_PARALLEL_COMPILE_JOBS "" CACHE STRING
   "Define the maximum number of concurrent compilation jobs.")
 if(LLVM_PARALLEL_COMPILE_JOBS)
 set(LLVM_PARALLEL_COMPILE_JOBS "" CACHE STRING
   "Define the maximum number of concurrent compilation jobs.")
 if(LLVM_PARALLEL_COMPILE_JOBS)

-  set_property(GLOBAL APPEND PROPERTY JOB_POOLS compile_job_pool=${LLVM_PARALLEL_COMPILE_JOBS})
-  set(CMAKE_JOB_POOL_COMPILE compile_job_pool)
+  if(CMAKE_VERSION VERSION_LESS 3.0 OR NOT CMAKE_MAKE_PROGRAM STREQUAL "ninja")
+    message(WARNING "Job pooling is only available with Ninja generators and CMake 3.0 and later.")
+  else()
+    set_property(GLOBAL APPEND PROPERTY JOB_POOLS compile_job_pool=${LLVM_PARALLEL_COMPILE_JOBS})
+    set(CMAKE_JOB_POOL_COMPILE compile_job_pool)
+  endif()

 endif()
 
 set(LLVM_PARALLEL_LINK_JOBS "" CACHE STRING
   "Define the maximum number of concurrent link jobs.")
 if(LLVM_PARALLEL_LINK_JOBS)
 endif()
 
 set(LLVM_PARALLEL_LINK_JOBS "" CACHE STRING
   "Define the maximum number of concurrent link jobs.")
 if(LLVM_PARALLEL_LINK_JOBS)

-  set_property(GLOBAL APPEND PROPERTY JOB_POOLS link_job_pool=${LLVM_PARALLEL_LINK_JOBS})
-  set(CMAKE_JOB_POOL_LINK link_job_pool)
+  if(CMAKE_VERSION VERSION_LESS 3.0 OR NOT CMAKE_MAKE_PROGRAM STREQUAL "ninja")
+    message(WARNING "Job pooling is only available with Ninja generators and CMake 3.0 and later.")
+  else()
+    set_property(GLOBAL APPEND PROPERTY JOB_POOLS link_job_pool=${LLVM_PARALLEL_LINK_JOBS})
+    set(CMAKE_JOB_POOL_LINK link_job_pool)
+  endif()

 endif()
 
 # Add path for custom modules
 endif()
 
 # Add path for custom modules