[CMake] Disallow direct configuration

As a first step, this allows us to generalize the detection of
standalone builds and make it fully compatible when building in
llvm/runtimes/ which automatically sets OPENMP_STANDLONE_BUILD.

Differential Revision: https://reviews.llvm.org/D40080

llvm-svn: 319341

4 files changed, 8 insertions, 20 deletions

diff --git a/openmp/runtime/Build_With_CMake.txt b/openmp/runtime/Build_With_CMake.txt
index 607e115eac0..ed1fb2649f3 100644
--- a/openmp/runtime/Build_With_CMake.txt
+++ b/openmp/runtime/Build_With_CMake.txt
@@ -51,7 +51,7 @@ How to call cmake initially, then repeatedly
 =====================
 Instructions to Build
 =====================
- $ cd libomp_top_level/ [ directory with src/ , exports/ , tools/ , etc. ]
+ $ cd openmp_top_level/ [ directory with runtime/, etc. ]
  $ mkdir build
  $ cd build
 
diff --git a/openmp/runtime/CMakeLists.txt b/openmp/runtime/CMakeLists.txt
index 1adc825b5f3..3a64c184316 100644
--- a/openmp/runtime/CMakeLists.txt
+++ b/openmp/runtime/CMakeLists.txt
@@ -9,21 +9,13 @@
 #//===----------------------------------------------------------------------===//
 #
 
-# CMAKE libomp
-cmake_minimum_required(VERSION 2.8 FATAL_ERROR)
+if("${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_CURRENT_SOURCE_DIR}")
+  message(FATAL_ERROR "Direct configuration not supported, please use parent directory!")
+endif()
 
 # Add cmake directory to search for custom cmake functions
 set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake ${CMAKE_MODULE_PATH})
 
-# Standalone build or part of LLVM?
-set(LIBOMP_STANDALONE_BUILD FALSE)
-if(OPENMP_STANDALONE_BUILD OR
-   "${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_CURRENT_SOURCE_DIR}" OR
-   "${CMAKE_SOURCE_DIR}/runtime" STREQUAL "${CMAKE_CURRENT_SOURCE_DIR}")
-  project(libomp C CXX)
-  set(LIBOMP_STANDALONE_BUILD TRUE)
-endif()
-
 # Set libomp version
 set(LIBOMP_VERSION_MAJOR 5)
 set(LIBOMP_VERSION_MINOR 0)
@@ -35,7 +27,7 @@ include(LibompHandleFlags)
 include(LibompDefinitions)
 
 # Determine the target architecture
-if(${LIBOMP_STANDALONE_BUILD})
+if(${OPENMP_STANDALONE_BUILD})
   # If adding a new architecture, take a look at cmake/LibompGetArchitecture.cmake
   libomp_get_architecture(LIBOMP_DETECTED_ARCH)
   set(LIBOMP_ARCH ${LIBOMP_DETECTED_ARCH} CACHE STRING
@@ -48,10 +40,6 @@ if(${LIBOMP_STANDALONE_BUILD})
     "enable assertions?")
   set(LIBOMP_ENABLE_WERROR FALSE CACHE BOOL
     "Enable -Werror flags to turn warnings into errors for supporting compilers.")
-  # CMAKE_BUILD_TYPE was not defined, set default to Release
-  if(NOT CMAKE_BUILD_TYPE)
-    set(CMAKE_BUILD_TYPE Release)
-  endif()
 else() # Part of LLVM build
   # Determine the native architecture from LLVM.
   string(TOLOWER "${LLVM_TARGET_ARCH}" LIBOMP_NATIVE_ARCH)
@@ -372,7 +360,7 @@ set(LIBOMP_INSTALL_ALIASES TRUE CACHE BOOL
   "Install libgomp and libiomp5 library aliases for backwards compatibility")
 
 # Print configuration after all variables are set.
-if(${LIBOMP_STANDALONE_BUILD})
+if(${OPENMP_STANDALONE_BUILD})
   libomp_say("Operating System     -- ${CMAKE_SYSTEM_NAME}")
   libomp_say("Target Architecture  -- ${LIBOMP_ARCH}")
   if(${MIC})
diff --git a/openmp/runtime/src/CMakeLists.txt b/openmp/runtime/src/CMakeLists.txt
index c4b56dbe545..cb2b1843a28 100644
--- a/openmp/runtime/src/CMakeLists.txt
+++ b/openmp/runtime/src/CMakeLists.txt
@@ -282,7 +282,7 @@ add_dependencies(libomp-micro-tests libomp-test-deps)
 # Install rules
 # We want to install libomp in DESTDIR/CMAKE_INSTALL_PREFIX/lib
 # We want to install headers in DESTDIR/CMAKE_INSTALL_PREFIX/include
-if(${LIBOMP_STANDALONE_BUILD})
+if(${OPENMP_STANDALONE_BUILD})
   set(LIBOMP_HEADERS_INSTALL_PATH include)
 else()
   string(REGEX MATCH "[0-9]+\\.[0-9]+(\\.[0-9]+)?" CLANG_VERSION ${PACKAGE_VERSION})
diff --git a/openmp/runtime/test/CMakeLists.txt b/openmp/runtime/test/CMakeLists.txt
index 9af5e177669..d384341d715 100644
--- a/openmp/runtime/test/CMakeLists.txt
+++ b/openmp/runtime/test/CMakeLists.txt
@@ -41,7 +41,7 @@ pythonize_bool(LIBOMP_HAVE_LIBATOMIC)
 set(LIBOMP_TEST_CFLAGS "" CACHE STRING
   "Extra compiler flags to send to the test compiler")
 
-if(${LIBOMP_STANDALONE_BUILD})
+if(${OPENMP_STANDALONE_BUILD})
   # Make sure we can use the console pool for recent cmake and ninja > 1.5
   if(CMAKE_VERSION VERSION_LESS 3.1.20141117)
     set(cmake_3_2_USES_TERMINAL)