# See www/CMake.html for instructions on how to build libcxx with CMake.

#===============================================================================
# Setup Project
#===============================================================================
cmake_minimum_required(VERSION 2.8)

if(POLICY CMP0042)
  cmake_policy(SET CMP0042 NEW) # Set MACOSX_RPATH=YES by default
endif()
if(POLICY CMP0022)
  cmake_policy(SET CMP0022 NEW) # Required when interacting with LLVM and Clang
endif()

project(libcxx CXX C)

set(PACKAGE_NAME libcxx)
set(PACKAGE_VERSION trunk-svn)
set(PACKAGE_STRING "${PACKAGE_NAME} ${PACKAGE_VERSION}")
set(PACKAGE_BUGREPORT "llvmbugs@cs.uiuc.edu")

# Add path for custom modules
set(CMAKE_MODULE_PATH
  "${CMAKE_CURRENT_SOURCE_DIR}/cmake"
  "${CMAKE_CURRENT_SOURCE_DIR}/cmake/Modules"
  ${CMAKE_MODULE_PATH}
  )

# 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."
 )

# Find the required bits of LLVM
include(FindLLVM)

#===============================================================================
# Setup CMake Options
#===============================================================================

# Basic options ---------------------------------------------------------------
option(LIBCXX_ENABLE_ASSERTIONS "Enable assertions independent of build mode." ON)
option(LIBCXX_ENABLE_SHARED "Build libc++ as a shared library." ON)

set(LIBCXX_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}" CACHE STRING
    "Define suffix of library directory name (32/64)")
option(LIBCXX_INSTALL_HEADERS "Install the libc++ headers." ON)
option(LIBCXX_INSTALL_SUPPORT_HEADERS "Install libc++ support headers." ON)

# ABI Library options ---------------------------------------------------------
set(LIBCXX_CXX_ABI "${LIBCXX_CXX_ABI}" CACHE STRING
    "Specify C++ ABI library to use." FORCE)
set(CXXABIS none libcxxabi libcxxrt libstdc++ libsupc++)
set_property(CACHE LIBCXX_CXX_ABI PROPERTY STRINGS ;${CXXABIS})

option(LIBCXX_ENABLE_STATIC_ABI_LIBRARY "Statically link the ABI library" OFF)

# Build libc++abi with libunwind. We need this option to determine whether to
# link with libunwind or libgcc_s while running the test cases.
option(LIBCXXABI_USE_LLVM_UNWINDER "Build and use the LLVM unwinder." OFF)

# Target options --------------------------------------------------------------
option(LIBCXX_BUILD_32_BITS "Build 32 bit libc++." OFF)
set(LIBCXX_SYSROOT "" CACHE STRING "Use alternate sysroot.")
set(LIBCXX_GCC_TOOLCHAIN "" CACHE STRING "Use alternate GCC toolchain.")

# Feature options -------------------------------------------------------------
option(LIBCXX_ENABLE_EXCEPTIONS "Use exceptions." ON)
option(LIBCXX_ENABLE_RTTI "Use run time type information." ON)
option(LIBCXX_ENABLE_GLOBAL_FILESYSTEM_NAMESPACE "Build libc++ with support for the global filesystem namespace." ON)
option(LIBCXX_ENABLE_STDIN "Build libc++ with support for stdin/std::cin." ON)
option(LIBCXX_ENABLE_STDOUT "Build libc++ with support for stdout/std::cout." ON)
option(LIBCXX_ENABLE_THREADS "Build libc++ with support for threads." ON)
option(LIBCXX_ENABLE_THREAD_UNSAFE_C_FUNCTIONS "Build libc++ with support for thread-unsafe C functions" ON)
option(LIBCXX_ENABLE_MONOTONIC_CLOCK
  "Build libc++ with support for a monotonic clock.
   This option may only be used when LIBCXX_ENABLE_THREADS=OFF." ON)

# Misc options ----------------------------------------------------------------
option(LIBCXX_ENABLE_PEDANTIC "Compile with pedantic enabled." ON)
option(LIBCXX_ENABLE_WERROR "Fail and stop if a warning is triggered." OFF)

option(LIBCXX_GENERATE_COVERAGE "Enable generating code coverage." OFF)
set(LIBCXX_COVERAGE_LIBRARY "" CACHE STRING
    "The Profile-rt library used to build with code coverage")

#===============================================================================
# Check option configurations
#===============================================================================

# Ensure LIBCXX_ENABLE_MONOTONIC_CLOCK is set to ON only when
# LIBCXX_ENABLE_THREADS is on.
if(LIBCXX_ENABLE_THREADS AND NOT LIBCXX_ENABLE_MONOTONIC_CLOCK)
  message(FATAL_ERROR "LIBCXX_ENABLE_MONOTONIC_CLOCK can only be set to OFF"
                      " when LIBCXX_ENABLE_THREADS is also set to OFF.")
endif()

# Ensure LLVM_USE_SANITIZER is not specified when LIBCXX_GENERATE_COVERAGE
# is ON.
if (LLVM_USE_SANITIZER AND LIBCXX_GENERATE_COVERAGE)
  message(FATAL_ERROR "LLVM_USE_SANITIZER cannot be used with LIBCXX_GENERATE_COVERAGE")
endif()

# Set LIBCXX_BUILD_32_BITS to (LIBCXX_BUILD_32_BITS OR LLVM_BUILD_32_BITS)
# and check that we can build with 32 bits if requested.
if (CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32)
  if (LIBCXX_BUILD_32_BITS OR LLVM_BUILD_32_BITS)
    if (NOT LLVM_BUILD_32_BITS) # Don't duplicate the output from LLVM
      message(STATUS "Building 32 bits executables and libraries.")
    endif()
    set(LIBCXX_BUILD_32_BITS ON CACHE BOOL "" FORCE)
  endif()
elseif(LIBCXX_BUILD_32_BITS)
  message(FATAL_ERROR "LIBCXX_BUILD_32_BITS=ON is not supported on this platform.")
endif()

# Check that this option is not enabled on Apple and emit a usage warning.
if (LIBCXX_ENABLE_STATIC_ABI_LIBRARY)
  if (APPLE)
    message(FATAL_ERROR "LIBCXX_ENABLE_STATIC_ABI_LIBRARY is not supported on OS X")
  else()
    message(WARNING "LIBCXX_ENABLE_STATIC_ABI_LIBRARY is an experimental option")
  endif()
endif()

#===============================================================================
# Configure System
#===============================================================================

set(LIBCXX_COMPILER    ${CMAKE_CXX_COMPILER})
set(LIBCXX_SOURCE_DIR  ${CMAKE_CURRENT_SOURCE_DIR})
set(LIBCXX_BINARY_DIR  ${CMAKE_CURRENT_BINARY_DIR})
set(LIBCXX_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBCXX_LIBDIR_SUFFIX})

set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LIBCXX_LIBRARY_DIR})
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LIBCXX_LIBRARY_DIR})

# Declare libc++ configuration variables.
# They are intended for use as follows:
# LIBCXX_CXX_FLAGS: General flags for both the compiler and linker.
# LIBCXX_COMPILE_FLAGS: Compile only flags.
# LIBCXX_LINK_FLAGS: Linker only flags.
set(LIBCXX_COMPILE_FLAGS "")
set(LIBCXX_LINK_FLAGS "")
set(LIBCXX_LIBRARIES "")

# Configure compiler.
include(config-ix)

# Configure coverage options.
if (LIBCXX_GENERATE_COVERAGE)
  include(CodeCoverage)
  set(CMAKE_BUILD_TYPE "COVERAGE" CACHE STRING "" FORCE)
endif()

string(TOUPPER "${CMAKE_BUILD_TYPE}" uppercase_CMAKE_BUILD_TYPE)

#===============================================================================
# Setup Compiler Flags
#===============================================================================

include(HandleLibCXXABI) # Steup the ABI library flags

# Include macros for adding and removing libc++ flags.
include(HandleLibcxxFlags)

# Remove flags that may have snuck in.
remove_flags(-DNDEBUG -UNDEBUG -D_DEBUG
             -stdlib=libc++ -stdlib=libstdc++ -lc++abi -m32)

# Required flags ==============================================================
add_compile_flags_if_supported(-std=c++11)
if (NOT MSVC AND NOT LIBCXX_SUPPORTS_STD_EQ_CXX11_FLAG)
  message(FATAL_ERROR "C++11 is required but the compiler does not support -std=c++11")
endif()

# On all systems the system c++ standard library headers need to be excluded.
# MSVC only has -X, which disables all default includes; including the crt.
# Thus, we do nothing and hope we don't accidentally include any of the C++
# headers
add_compile_flags_if_supported(-nostdinc++)

# Target flags ================================================================
add_flags_if(LIBCXX_BUILD_32_BITS -m32)
add_flags_if(LIBCXX_TARGET_TRIPLE "-target ${LIBCXX_TARGET_TRIPLE}")
add_flags_if(LIBCXX_SYSROOT "--sysroot ${LIBCXX_SYSROOT}")
add_flags_if(LIBCXX_GCC_TOOLCHAIN "-gcc-toolchain ${LIBCXX_GCC_TOOLCHAIN}")

# Warning flags ===============================================================
add_definitions(-D_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
add_compile_flags_if_supported(
    -Wall -W -Wwrite-strings
    -Wno-unused-parameter -Wno-long-long
    -Werror=return-type)
if (LIBCXX_ENABLE_WERROR)
  add_compile_flags_if_supported(-Werror)
  add_compile_flags_if_supported(-WX)
endif()
if (LIBCXX_ENABLE_PEDANTIC)
  add_compile_flags_if_supported(-pedantic)
endif()

# Exception flags =============================================================
if (LIBCXX_ENABLE_EXCEPTIONS)
  # Catches C++ exceptions only and tells the compiler to assume that extern C
  # functions never throw a C++ exception.
  add_compile_flags_if_supported(-EHsc)
else()
  add_definitions(-D_LIBCPP_NO_EXCEPTIONS)
  add_compile_flags_if_supported(-EHs- -EHa-)
  add_compile_flags_if_supported(-fno-exceptions)
endif()

# RTTI flags ==================================================================
if (NOT LIBCXX_ENABLE_RTTI)
  add_definitions(-D_LIBCPP_NO_RTTI)
  add_compile_flags_if_supported(-GR-)
  add_compile_flags_if_supported(-fno-rtti)
endif()

# Assertion flags =============================================================
define_if(LIBCXX_ENABLE_ASSERTIONS -UNDEBUG)
define_if_not(LIBCXX_ENABLE_ASSERTIONS -DNDEBUG)
if (LIBCXX_ENABLE_ASSERTIONS)
  # MSVC doesn't like _DEBUG on release builds. See PR 4379.
  define_if_not(MSVC -D_DEBUG)
endif()

# Feature flags ===============================================================
define_if(MSVC -D_CRT_SECURE_NO_WARNINGS)
define_if_not(LIBCXX_ENABLE_GLOBAL_FILESYSTEM_NAMESPACE -D_LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE)
define_if_not(LIBCXX_ENABLE_STDIN -D_LIBCPP_HAS_NO_STDIN)
define_if_not(LIBCXX_ENABLE_STDOUT -D_LIBCPP_HAS_NO_STDOUT)
define_if_not(LIBCXX_ENABLE_THREADS -D_LIBCPP_HAS_NO_THREADS)
define_if_not(LIBCXX_ENABLE_MONOTONIC_CLOCK -D_LIBCPP_HAS_NO_MONOTONIC_CLOCK)
define_if_not(LIBCXX_ENABLE_THREAD_UNSAFE_C_FUNCTIONS -D_LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS)

#===============================================================================
# Setup Source Code And Tests
#===============================================================================
include_directories(include)
add_subdirectory(include)
add_subdirectory(lib)
add_subdirectory(test)