[libcxxabi] Rework CMakeLists.txt into modules

Refactor cmake to remove dependence on LLVM's cmake modules.
This improves handling of cmake checks when cross compiling and brings
libcxxabi in line with libcxx and other project modules.

Differential revision: https://reviews.llvm.org/D33635

git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@304374 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 60 insertions, 153 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 07ad0c6..b7363dd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,3 +1,5 @@
+# See www/CMake.html for instructions on how to build libcxxabi with CMake.
+
 #===============================================================================
 # Setup Project
 #===============================================================================
@@ -16,121 +18,28 @@ set(CMAKE_MODULE_PATH
   )
 
 if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
-  project(libcxxabi)
-
-  # Rely on llvm-config.
-  set(CONFIG_OUTPUT)
-  if (NOT LLVM_CONFIG_PATH)
-    find_program(LLVM_CONFIG_PATH "llvm-config")
-  endif()
-  if(DEFINED LLVM_PATH)
-    set(LLVM_INCLUDE_DIR ${LLVM_INCLUDE_DIR} CACHE PATH "Path to llvm/include")
-    set(LLVM_PATH ${LLVM_PATH} CACHE PATH "Path to LLVM source tree")
-    set(LLVM_MAIN_SRC_DIR ${LLVM_PATH})
-    set(LLVM_CMAKE_PATH "${LLVM_PATH}/cmake/modules")
-  elseif(LLVM_CONFIG_PATH)
-    message(STATUS "Found LLVM_CONFIG_PATH as ${LLVM_CONFIG_PATH}")
-    set(CONFIG_COMMAND ${LLVM_CONFIG_PATH}
-      "--includedir"
-      "--prefix"
-      "--src-root")
-    execute_process(
-      COMMAND ${CONFIG_COMMAND}
-      RESULT_VARIABLE HAD_ERROR
-      OUTPUT_VARIABLE CONFIG_OUTPUT
-    )
-    if(NOT HAD_ERROR)
-      string(REGEX REPLACE
-        "[ \t]*[\r\n]+[ \t]*" ";"
-        CONFIG_OUTPUT ${CONFIG_OUTPUT})
-    else()
-      string(REPLACE ";" " " CONFIG_COMMAND_STR "${CONFIG_COMMAND}")
-      message(STATUS "${CONFIG_COMMAND_STR}")
-      message(FATAL_ERROR "llvm-config failed with status ${HAD_ERROR}")
-    endif()
-
-    list(GET CONFIG_OUTPUT 0 INCLUDE_DIR)
-    list(GET CONFIG_OUTPUT 1 LLVM_OBJ_ROOT)
-    list(GET CONFIG_OUTPUT 2 MAIN_SRC_DIR)
-
-    set(LLVM_INCLUDE_DIR ${INCLUDE_DIR} CACHE PATH "Path to llvm/include")
-    set(LLVM_BINARY_DIR ${LLVM_OBJ_ROOT} CACHE PATH "Path to LLVM build tree")
-    set(LLVM_MAIN_SRC_DIR ${MAIN_SRC_DIR} CACHE PATH "Path to LLVM source tree")
-    set(LLVM_LIT_PATH "${LLVM_PATH}/utils/lit/lit.py")
-
-    # --cmakedir is supported since llvm r291218 (4.0 release)
-    execute_process(
-      COMMAND ${LLVM_CONFIG_PATH} --cmakedir
-      RESULT_VARIABLE HAD_ERROR
-      OUTPUT_VARIABLE CONFIG_OUTPUT
-      ERROR_QUIET)
-    if(NOT HAD_ERROR)
-      string(STRIP "${CONFIG_OUTPUT}" LLVM_CMAKE_PATH)
-    else()
-      set(LLVM_CMAKE_PATH
-          "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
-    endif()
-  else()
-    message(FATAL_ERROR "llvm-config not found and LLVM_MAIN_SRC_DIR not defined. "
-                        "Reconfigure with -DLLVM_CONFIG_PATH=path/to/llvm-config "
-                        "or -DLLVM_PATH=path/to/llvm-source-root.")
-  endif()
-
-  if(EXISTS ${LLVM_CMAKE_PATH})
-    list(APPEND CMAKE_MODULE_PATH "${LLVM_CMAKE_PATH}")
-    include("${LLVM_CMAKE_PATH}/AddLLVM.cmake")
-    include("${LLVM_CMAKE_PATH}/HandleLLVMOptions.cmake")
-  else()
-    message(FATAL_ERROR "Not found: ${LLVM_CMAKE_PATH}")
-  endif()
+  project(libcxxabi CXX C)
 
   set(PACKAGE_NAME libcxxabi)
   set(PACKAGE_VERSION 5.0.0svn)
   set(PACKAGE_STRING "${PACKAGE_NAME} ${PACKAGE_VERSION}")
   set(PACKAGE_BUGREPORT "llvm-bugs@lists.llvm.org")
 
-  if (NOT DEFINED LLVM_INCLUDE_TESTS)
-    set(LLVM_INCLUDE_TESTS ON)
-  endif()
-
-  if(EXISTS ${LLVM_MAIN_SRC_DIR}/utils/lit/lit.py)
-    set(LLVM_LIT ${LLVM_MAIN_SRC_DIR}/utils/lit/lit.py)
-  else()
-    # Seek installed Lit.
-    find_program(LLVM_LIT "lit.py" ${LLVM_MAIN_SRC_DIR}/utils/lit
-      DOC "Path to lit.py")
-  endif()
-
-  if(LLVM_LIT)
-    # Define the default arguments to use with 'lit', and an option for the user
-    # to override.
-    set(LIT_ARGS_DEFAULT "-sv")
-    if (MSVC OR XCODE)
-      set(LIT_ARGS_DEFAULT "${LIT_ARGS_DEFAULT} --no-progress-bar")
-    endif()
-    set(LLVM_LIT_ARGS "${LIT_ARGS_DEFAULT}" CACHE STRING "Default options for lit")
-
-    # On Win32 hosts, provide an option to specify the path to the GnuWin32 tools.
-    if( WIN32 AND NOT CYGWIN )
-      set(LLVM_LIT_TOOLS_DIR "" CACHE PATH "Path to GnuWin32 tools")
-    endif()
-  else()
-    set(LLVM_INCLUDE_TESTS OFF)
-  endif()
-
-  set(LIBCXXABI_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}" CACHE STRING
-      "Define suffix of library directory name (32/64)")
-
-  set(LIBCXXABI_STANDALONE_BUILD 1)
-else()
-  set(LLVM_MAIN_SRC_DIR "${CMAKE_SOURCE_DIR}" CACHE PATH "Path to LLVM source tree")
-  set(LLVM_LIT "${CMAKE_SOURCE_DIR}/utils/lit/lit.py")
-  set(LIBCXXABI_LIBDIR_SUFFIX ${LLVM_LIBDIR_SUFFIX})
+  # Find the LLVM sources and simulate LLVM CMake options.
+  include(HandleOutOfTreeLLVM)
 endif()
 
+# Require out of source build.
+include(MacroEnsureOutOfSourceBuild)
+MACRO_ENSURE_OUT_OF_SOURCE_BUILD(
+ "${PROJECT_NAME} requires an out of source build. Please create a separate
+ build directory and run 'cmake /path/to/${PROJECT_NAME} [options]' there."
+ )
+
 #===============================================================================
 # Setup CMake Options
 #===============================================================================
+include(CMakeDependentOption)
 include(HandleCompilerRT)
 
 # Define options.
@@ -247,6 +156,7 @@ endif()
 
 set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LIBCXXABI_LIBRARY_DIR})
 set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LIBCXXABI_LIBRARY_DIR})
+set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${LIBCXXABI_LIBRARY_DIR})
 
 # By default, for non-standalone builds, libcxx and libcxxabi share a library
 # directory.
@@ -264,30 +174,26 @@ elseif(LIBCXXABI_BUILD_32_BITS)
   message(FATAL_ERROR "LIBCXXABI_BUILD_32_BITS=ON is not supported on this platform.")
 endif()
 
-#===============================================================================
-# Setup Compiler Flags
-#===============================================================================
-
-# Get required flags.
-macro(append_if list condition var)
-  if (${condition})
-    list(APPEND ${list} ${var})
-  endif()
-endmacro()
-
-macro(add_target_flags_if condition var)
-  if (${condition})
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${var}")
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${var}")
-    list(APPEND LIBCXXABI_COMPILE_FLAGS ${var})
-    list(APPEND LIBCXXABI_LINK_FLAGS ${var})
-  endif()
-endmacro()
+# Declare libc++abi configuration variables.
+# They are intended for use as follows:
+# LIBCXXABI_C_FLAGS: General flags for both the c++ compiler and linker.
+# LIBCXXABI_CXX_FLAGS: General flags for both the c++ compiler and linker.
+# LIBCXXABI_COMPILE_FLAGS: Compile only flags.
+# LIBCXXABI_LINK_FLAGS: Linker only flags.
+# LIBCXXABI_LIBRARIES: libraries libc++abi is linked to.
 
 set(LIBCXXABI_C_FLAGS "")
 set(LIBCXXABI_CXX_FLAGS "")
 set(LIBCXXABI_COMPILE_FLAGS "")
 set(LIBCXXABI_LINK_FLAGS "")
+set(LIBCXXABI_LIBRARIES "")
+
+# Include macros for adding and removing libc++abi flags.
+include(HandleLibcxxabiFlags)
+
+#===============================================================================
+# Setup Compiler Flags
+#===============================================================================
 
 # Configure target flags
 add_target_flags_if(LIBCXXABI_BUILD_32_BITS "-m32")
@@ -325,53 +231,54 @@ if (WIN32 AND LIBCXXABI_ENABLE_STATIC AND NOT LIBCXXABI_ENABLE_SHARED)
   add_definitions(-D_LIBCXXABI_DISABLE_VISIBILITY_ANNOTATIONS)
 endif()
 
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WERROR_FLAG -Werror=return-type)
+add_compile_flags_if_supported(-Werror=return-type)
 
 # Get warning flags
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_W_FLAG -W)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WALL_FLAG -Wall)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WCHAR_SUBSCRIPTS_FLAG -Wchar-subscripts)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WCONVERSION_FLAG -Wconversion)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WMISMATCHED_TAGS_FLAG -Wmismatched-tags)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WMISSING_BRACES_FLAG -Wmissing-braces)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WNEWLINE_EOF_FLAG -Wnewline-eof)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WUNUSED_FUNCTION_FLAG -Wunused-function)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WSHADOW_FLAG -Wshadow)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WSHORTEN_64_TO_32_FLAG -Wshorten-64-to-32)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WSIGN_COMPARE_FLAG -Wsign-compare)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WSIGN_CONVERSION_FLAG -Wsign-conversion)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WSTRICT_ALIASING_FLAG -Wstrict-aliasing=2)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WSTRICT_OVERFLOW_FLAG -Wstrict-overflow=4)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WUNUSED_PARAMETER_FLAG -Wunused-parameter)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WUNUSED_VARIABLE_FLAG -Wunused-variable)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WWRITE_STRINGS_FLAG -Wwrite-strings)
-append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WUNDEF_FLAG -Wundef)
+add_compile_flags_if_supported(-W)
+add_compile_flags_if_supported(-Wall)
+add_compile_flags_if_supported(-Wchar-subscripts)
+add_compile_flags_if_supported(-Wconversion)
+add_compile_flags_if_supported(-Wmismatched-tags)
+add_compile_flags_if_supported(-Wmissing-braces)
+add_compile_flags_if_supported(-Wnewline-eof)
+add_compile_flags_if_supported(-Wunused-function)
+add_compile_flags_if_supported(-Wshadow)
+add_compile_flags_if_supported(-Wshorten-64-to-32)
+add_compile_flags_if_supported(-Wsign-compare)
+add_compile_flags_if_supported(-Wsign-conversion)
+add_compile_flags_if_supported(-Wstrict-aliasing=2)
+add_compile_flags_if_supported(-Wstrict-overflow=4)
+add_compile_flags_if_supported(-Wunused-parameter)
+add_compile_flags_if_supported(-Wunused-variable)
+add_compile_flags_if_supported(-Wwrite-strings)
+add_compile_flags_if_supported(-Wundef)
 
 if (LIBCXXABI_ENABLE_WERROR)
-  append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WERROR_FLAG -Werror)
-  append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WX_FLAG -WX)
+  add_compile_flags_if_supported(-Werror)
+  add_compile_flags_if_supported(-WX)
 else()
-  append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WNO_ERROR_FLAG -Wno-error)
-  append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_NO_WX_FLAG -WX-)
+  add_compile_flags_if_supported(-Wno-error)
+  add_compile_flags_if_supported(-WX-)
 endif()
 if (LIBCXXABI_ENABLE_PEDANTIC)
-  append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_PEDANTIC_FLAG -pedantic)
+  add_compile_flags_if_supported(-pedantic)
 endif()
 
 # Get feature flags.
-append_if(LIBCXXABI_CXX_FLAGS LIBCXXABI_HAS_FSTRICT_ALIASING_FLAG -fstrict-aliasing)
+add_compile_flags_if_supported(-fstrict-aliasing)
 
 # Exceptions
 if (LIBCXXABI_ENABLE_EXCEPTIONS)
   # Catches C++ exceptions only and tells the compiler to assume that extern C
   # functions never throw a C++ exception.
-  append_if(LIBCXXABI_CXX_FLAGS LIBCXXABI_HAS_EHSC_FLAG -EHsc)
-  append_if(LIBCXXABI_C_FLAGS LIBCXXABI_HAS_FUNWIND_TABLES -funwind-tables)
+  add_compile_flags_if_supported(-EHsc)
+  # Do we really need to be run through the C compiler ?
+  add_c_compile_flags_if_supported(-funwind-tables)
 else()
   add_definitions(-D_LIBCXXABI_NO_EXCEPTIONS)
-  append_if(LIBCXXABI_CXX_FLAGS LIBCXXABI_HAS_NO_EXCEPTIONS_FLAG -fno-exceptions)
-  append_if(LIBCXXABI_CXX_FLAGS LIBCXXABI_HAS_NO_EHS_FLAG -EHs-)
-  append_if(LIBCXXABI_CXX_FLAGS LIBCXXABI_HAS_NO_EHA_FLAG -EHa-)
+  add_compile_flags_if_supported(-fno-exceptions)
+  add_compile_flags_if_supported(-EHs-)
+  add_compile_flags_if_supported(-EHa-)
 endif()
 
 # Assert