runtime/CMakeLists.txt - llvm-project/flang - Git at Google

 #===-- runtime/CMakeLists.txt ----------------------------------------------===#
 #
 # Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 # See https://llvm.org/LICENSE.txt for license information.
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 #
 #===------------------------------------------------------------------------===#

 if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
   cmake_minimum_required(VERSION 3.20.0)

   project(FlangRuntime C CXX)

   set(CMAKE_CXX_STANDARD 17)
   set(CMAKE_CXX_STANDARD_REQUIRED TRUE)
   set(CMAKE_CXX_EXTENSIONS OFF)

   set(FLANG_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/..")

   set(LLVM_COMMON_CMAKE_UTILS "${FLANG_SOURCE_DIR}/../cmake")
   set(LLVM_CMAKE_UTILS "${FLANG_SOURCE_DIR}/../llvm/cmake")
   set(CLANG_CMAKE_UTILS "${FLANG_SOURCE_DIR}/../clang/cmake")

   # Add path for custom modules
   list(INSERT CMAKE_MODULE_PATH 0
     "${FLANG_SOURCE_DIR}/cmake"
     "${FLANG_SOURCE_DIR}/cmake/modules"
     "${LLVM_COMMON_CMAKE_UTILS}"
     "${LLVM_COMMON_CMAKE_UTILS}/Modules"
     "${LLVM_CMAKE_UTILS}"
     "${LLVM_CMAKE_UTILS}/modules"
     "${CLANG_CMAKE_UTILS}/modules"
     )

   include(AddClang)
   include(AddLLVM)
   include(AddFlang)
   include(HandleLLVMOptions)

   include(TestBigEndian)
   test_big_endian(IS_BIGENDIAN)
   if (IS_BIGENDIAN)
     add_compile_definitions(FLANG_BIG_ENDIAN=1)
   else ()
     add_compile_definitions(FLANG_LITTLE_ENDIAN=1)
   endif ()
   include_directories(BEFORE
     ${FLANG_SOURCE_DIR}/include)

   # The out of tree builds of the compiler and the Fortran runtime
   # must use the same setting of FLANG_RUNTIME_F128_MATH_LIB
   # to be composable. Failure to synchronize this setting may result
   # in linking errors or fatal failures in F128 runtime functions.
   set(FLANG_RUNTIME_F128_MATH_LIB "" CACHE STRING
     "Specifies the target library used for implementing IEEE-754 128-bit float \
     math in F18 runtime, e.g. it might be libquadmath for targets where \
     REAL(16) is mapped to __float128, or libm for targets where REAL(16) \
     is mapped to long double, etc."
     )
 endif()

 include(CheckCXXSymbolExists)
 include(CheckCXXSourceCompiles)
 check_cxx_symbol_exists(strerror_r string.h HAVE_STRERROR_R)
 # Can't use symbol exists here as the function is overloaded in C++
 check_cxx_source_compiles(
   "#include <string.h>
    int main() {
      char buf[4096];
      return strerror_s(buf, 4096, 0);
    }
   "
   HAVE_DECL_STRERROR_S)

 # Check if 128-bit float computations can be done via long double.
 check_cxx_source_compiles(
   "#include <cfloat>
    #if LDBL_MANT_DIG != 113
    #error LDBL_MANT_DIG != 113
    #endif
    int main() { return 0; }
   "
   HAVE_LDBL_MANT_DIG_113)

 check_cxx_compiler_flag(-fno-lto FLANG_RUNTIME_HAS_FNO_LTO_FLAG)
 if (FLANG_RUNTIME_HAS_FNO_LTO_FLAG)
   set(NO_LTO_FLAGS "-fno-lto")
 else()
   set(NO_LTO_FLAGS "")
 endif()

 configure_file(config.h.cmake config.h)
 # include_directories is used here instead of target_include_directories
 # because add_flang_library creates multiple objects (STATIC/SHARED, OBJECT)
 # with different names
 include_directories(AFTER ${CMAKE_CURRENT_BINARY_DIR})

 append(${NO_LTO_FLAGS} CMAKE_C_FLAGS)
 append(${NO_LTO_FLAGS} CMAKE_CXX_FLAGS)

 # Disable libstdc++/libc++ assertions, even in an LLVM_ENABLE_ASSERTIONS build,
 # to avoid an unwanted dependency on libstdc++/libc++.so.
 add_definitions(-U_GLIBCXX_ASSERTIONS)
 add_definitions(-U_LIBCPP_ENABLE_ASSERTIONS)

 add_subdirectory(FortranMain)
 add_subdirectory(Float128Math)

 set(sources
   ISO_Fortran_binding.cpp
   allocatable.cpp
   array-constructor.cpp
   assign.cpp
   buffer.cpp
   character.cpp
   command.cpp
   complex-powi.cpp
   complex-reduction.c
   connection.cpp
   copy.cpp
   derived-api.cpp
   derived.cpp
   descriptor-io.cpp
   descriptor.cpp
   dot-product.cpp
   edit-input.cpp
   edit-output.cpp
   environment.cpp
   exceptions.cpp
   execute.cpp
   extensions.cpp
   external-unit.cpp
   extrema.cpp
   file.cpp
   findloc.cpp
   format.cpp
   inquiry.cpp
   internal-unit.cpp
   io-api.cpp
   io-error.cpp
   io-stmt.cpp
   iostat.cpp
   main.cpp
   matmul-transpose.cpp
   matmul.cpp
   memory.cpp
   misc-intrinsic.cpp
   namelist.cpp
   non-tbp-dio.cpp
   numeric.cpp
   pointer.cpp
   product.cpp
   pseudo-unit.cpp
   ragged.cpp
   random.cpp
   reduce.cpp
   reduction.cpp
   stat.cpp
   stop.cpp
   sum.cpp
   support.cpp
   temporary-stack.cpp
   terminator.cpp
   time-intrinsic.cpp
   tools.cpp
   transformational.cpp
   type-code.cpp
   type-info.cpp
   unit-map.cpp
   unit.cpp
   utf.cpp
 )

 option(FLANG_EXPERIMENTAL_CUDA_RUNTIME
   "Compile Fortran runtime as CUDA sources (experimental)" OFF
   )
 set(FLANG_LIBCUDACXX_PATH "" CACHE PATH "Path to libcu++ package installation")

 # List of files that are buildable for all devices.
 set(supported_files
   ISO_Fortran_binding.cpp
   allocatable.cpp
   array-constructor.cpp
   assign.cpp
   buffer.cpp
   character.cpp
   connection.cpp
   copy.cpp
   derived-api.cpp
   derived.cpp
   descriptor.cpp
   descriptor-io.cpp
   dot-product.cpp
   edit-input.cpp
   edit-output.cpp
   environment.cpp
   extrema.cpp
   external-unit.cpp
   findloc.cpp
   format.cpp
   inquiry.cpp
   internal-unit.cpp
   io-api.cpp
   io-error.cpp
   io-stmt.cpp
   iostat.cpp
   matmul-transpose.cpp
   matmul.cpp
   memory.cpp
   misc-intrinsic.cpp
   namelist.cpp
   non-tbp-dio.cpp
   numeric.cpp
   pointer.cpp
   product.cpp
   pseudo-unit.cpp
   ragged.cpp
   stat.cpp
   sum.cpp
   support.cpp
   terminator.cpp
   tools.cpp
   transformational.cpp
   type-code.cpp
   type-info.cpp
   unit.cpp
   utf.cpp
   )

 if (FLANG_EXPERIMENTAL_CUDA_RUNTIME)
   if (BUILD_SHARED_LIBS)
     message(FATAL_ERROR
       "BUILD_SHARED_LIBS is not supported for CUDA build of Fortran runtime"
       )
   endif()

   enable_language(CUDA)

   # TODO: figure out how to make target property CUDA_SEPARABLE_COMPILATION
   # work, and avoid setting CMAKE_CUDA_SEPARABLE_COMPILATION.
   set(CMAKE_CUDA_SEPARABLE_COMPILATION ON)

   # Treat all supported sources as CUDA files.
   set_source_files_properties(${supported_files} PROPERTIES LANGUAGE CUDA)
   set(CUDA_COMPILE_OPTIONS)
   if ("${CMAKE_CUDA_COMPILER_ID}" MATCHES "Clang")
     # Allow varargs.
     set(CUDA_COMPILE_OPTIONS
       -Xclang -fcuda-allow-variadic-functions
       )
   endif()
   if ("${CMAKE_CUDA_COMPILER_ID}" MATCHES "NVIDIA")
     set(CUDA_COMPILE_OPTIONS
       --expt-relaxed-constexpr
       # Disable these warnings:
       #   'long double' is treated as 'double' in device code
       -Xcudafe --diag_suppress=20208
       -Xcudafe --display_error_number
       )
   endif()
   set_source_files_properties(${supported_files} PROPERTIES COMPILE_OPTIONS
     "${CUDA_COMPILE_OPTIONS}"
     )

   if (EXISTS "${FLANG_LIBCUDACXX_PATH}/include")
     # When using libcudacxx headers files, we have to use them
     # for all files of F18 runtime.
     include_directories(AFTER ${FLANG_LIBCUDACXX_PATH}/include)
     add_compile_definitions(RT_USE_LIBCUDACXX=1)
   endif()
 endif()

 set(FLANG_EXPERIMENTAL_OMP_OFFLOAD_BUILD "off" CACHE STRING
   "Compile Fortran runtime as OpenMP target offload sources (experimental). Valid options are 'off', 'host_device', 'nohost'")

 set(FLANG_OMP_DEVICE_ARCHITECTURES "all" CACHE STRING
   "List of OpenMP device architectures to be used to compile the Fortran runtime (e.g. 'gfx1103;sm_90')")

 if (NOT FLANG_EXPERIMENTAL_OMP_OFFLOAD_BUILD STREQUAL "off")
   # 'host_device' build only works with Clang compiler currently.
   # The build is done with the CMAKE_C/CXX_COMPILER, i.e. it does not use
   # the in-tree built Clang. We may have a mode that would use the in-tree
   # built Clang.
   #
   # 'nohost' is supposed to produce an LLVM Bitcode library,
   # and it has to be done with a C/C++ compiler producing LLVM Bitcode
   # compatible with the LLVM toolchain version distributed with the Flang
   # compiler.
   # In general, the in-tree built Clang should be used for 'nohost' build.
   # Note that 'nohost' build does not produce the host version of Flang
   # runtime library, so there will be two separate distributable objects.
   # 'nohost' build is a TODO.

   if (NOT FLANG_EXPERIMENTAL_OMP_OFFLOAD_BUILD STREQUAL "host_device")
     message(FATAL_ERROR "Unsupported OpenMP offload build of Flang runtime")
   endif()
   if (BUILD_SHARED_LIBS)
     message(FATAL_ERROR
       "BUILD_SHARED_LIBS is not supported for OpenMP offload build of Fortran runtime"
       )
   endif()

   if ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" AND
       "${CMAKE_C_COMPILER_ID}" MATCHES "Clang")

     set(all_amdgpu_architectures
       "gfx700;gfx701;gfx801;gfx803;gfx900;gfx902;gfx906"
       "gfx908;gfx90a;gfx90c;gfx940;gfx1010;gfx1030"
       "gfx1031;gfx1032;gfx1033;gfx1034;gfx1035;gfx1036"
       "gfx1100;gfx1101;gfx1102;gfx1103;gfx1150;gfx1151"
       )
     set(all_nvptx_architectures
       "sm_35;sm_37;sm_50;sm_52;sm_53;sm_60;sm_61;sm_62"
       "sm_70;sm_72;sm_75;sm_80;sm_86;sm_89;sm_90"
       )
     set(all_gpu_architectures
       "${all_amdgpu_architectures};${all_nvptx_architectures}"
       )
     # TODO: support auto detection on the build system.
     if (FLANG_OMP_DEVICE_ARCHITECTURES STREQUAL "all")
       set(FLANG_OMP_DEVICE_ARCHITECTURES ${all_gpu_architectures})
     endif()
     list(REMOVE_DUPLICATES FLANG_OMP_DEVICE_ARCHITECTURES)

     string(REPLACE ";" "," compile_for_architectures
       "${FLANG_OMP_DEVICE_ARCHITECTURES}"
       )

     set(OMP_COMPILE_OPTIONS
       -fopenmp
       -fvisibility=hidden
       -fopenmp-cuda-mode
       --offload-arch=${compile_for_architectures}
       # Force LTO for the device part.
       -foffload-lto
       )
     set_source_files_properties(${supported_files} PROPERTIES COMPILE_OPTIONS
       "${OMP_COMPILE_OPTIONS}"
       )

     # Enable "declare target" in the source code.
     set_source_files_properties(${supported_files}
       PROPERTIES COMPILE_DEFINITIONS OMP_OFFLOAD_BUILD
       )
   else()
     message(FATAL_ERROR
       "Flang runtime build is not supported for these compilers:\n"
       "CMAKE_CXX_COMPILER_ID: ${CMAKE_CXX_COMPILER_ID}\n"
       "CMAKE_C_COMPILER_ID: ${CMAKE_C_COMPILER_ID}")
   endif()
 endif()

 if (NOT TARGET FortranFloat128Math)
   # If FortranFloat128Math is not defined, then we are not building
   # standalone FortranFloat128Math library. Instead, include
   # the relevant sources into FortranRuntime itself.
   # The information is provided via FortranFloat128MathILib
   # interface library.
   get_target_property(f128_sources
     FortranFloat128MathILib INTERFACE_SOURCES
     )
   if (f128_sources)
     # The interface may define special macros for Float128Math files,
     # so we need to propagate them.
     get_target_property(f128_defs
       FortranFloat128MathILib INTERFACE_COMPILE_DEFINITIONS
       )
     set_property(SOURCE ${f128_sources}
       APPEND PROPERTY COMPILE_DEFINITIONS
       ${f128_defs}
       )
     list(APPEND sources ${f128_sources})
   endif()
 endif()

 if (NOT DEFINED MSVC)
   add_flang_library(FortranRuntime
     ${sources}
     LINK_LIBS
     FortranDecimal

     INSTALL_WITH_TOOLCHAIN
   )
 else()
   add_flang_library(FortranRuntime
     ${sources}
     LINK_LIBS
     FortranDecimal
   )
   set(CMAKE_MSVC_RUNTIME_LIBRARY MultiThreaded)
   add_flang_library(FortranRuntime.static ${sources}
     LINK_LIBS
     FortranDecimal.static
     INSTALL_WITH_TOOLCHAIN)
   set(CMAKE_MSVC_RUNTIME_LIBRARY MultiThreadedDLL)
   add_flang_library(FortranRuntime.dynamic ${sources}
     LINK_LIBS
     FortranDecimal.dynamic
     INSTALL_WITH_TOOLCHAIN)
   set(CMAKE_MSVC_RUNTIME_LIBRARY MultiThreadedDebug)
   add_flang_library(FortranRuntime.static_dbg ${sources}
     LINK_LIBS
     FortranDecimal.static_dbg
     INSTALL_WITH_TOOLCHAIN)
   set(CMAKE_MSVC_RUNTIME_LIBRARY MultiThreadedDebugDLL)
   add_flang_library(FortranRuntime.dynamic_dbg ${sources}
     LINK_LIBS
     FortranDecimal.dynamic_dbg
     INSTALL_WITH_TOOLCHAIN)
   add_dependencies(FortranRuntime FortranRuntime.static FortranRuntime.dynamic
     FortranRuntime.static_dbg FortranRuntime.dynamic_dbg)
 endif()
	#===-- runtime/CMakeLists.txt ----------------------------------------------===#
	#
	# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	# See https://llvm.org/LICENSE.txt for license information.
	# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	#
	#===------------------------------------------------------------------------===#

	if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
	cmake_minimum_required(VERSION 3.20.0)

	project(FlangRuntime C CXX)

	set(CMAKE_CXX_STANDARD 17)
	set(CMAKE_CXX_STANDARD_REQUIRED TRUE)
	set(CMAKE_CXX_EXTENSIONS OFF)

	set(FLANG_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/..")

	set(LLVM_COMMON_CMAKE_UTILS "${FLANG_SOURCE_DIR}/../cmake")
	set(LLVM_CMAKE_UTILS "${FLANG_SOURCE_DIR}/../llvm/cmake")
	set(CLANG_CMAKE_UTILS "${FLANG_SOURCE_DIR}/../clang/cmake")

	# Add path for custom modules
	list(INSERT CMAKE_MODULE_PATH 0
	"${FLANG_SOURCE_DIR}/cmake"
	"${FLANG_SOURCE_DIR}/cmake/modules"
	"${LLVM_COMMON_CMAKE_UTILS}"
	"${LLVM_COMMON_CMAKE_UTILS}/Modules"
	"${LLVM_CMAKE_UTILS}"
	"${LLVM_CMAKE_UTILS}/modules"
	"${CLANG_CMAKE_UTILS}/modules"
	)

	include(AddClang)
	include(AddLLVM)
	include(AddFlang)
	include(HandleLLVMOptions)

	include(TestBigEndian)
	test_big_endian(IS_BIGENDIAN)
	if (IS_BIGENDIAN)
	add_compile_definitions(FLANG_BIG_ENDIAN=1)
	else ()
	add_compile_definitions(FLANG_LITTLE_ENDIAN=1)
	endif ()
	include_directories(BEFORE
	${FLANG_SOURCE_DIR}/include)

	# The out of tree builds of the compiler and the Fortran runtime
	# must use the same setting of FLANG_RUNTIME_F128_MATH_LIB
	# to be composable. Failure to synchronize this setting may result
	# in linking errors or fatal failures in F128 runtime functions.
	set(FLANG_RUNTIME_F128_MATH_LIB "" CACHE STRING
	"Specifies the target library used for implementing IEEE-754 128-bit float \
	math in F18 runtime, e.g. it might be libquadmath for targets where \
	REAL(16) is mapped to __float128, or libm for targets where REAL(16) \
	is mapped to long double, etc."
	)
	endif()

	include(CheckCXXSymbolExists)
	include(CheckCXXSourceCompiles)
	check_cxx_symbol_exists(strerror_r string.h HAVE_STRERROR_R)
	# Can't use symbol exists here as the function is overloaded in C++
	check_cxx_source_compiles(
	"#include <string.h>
	int main() {
	char buf[4096];
	return strerror_s(buf, 4096, 0);
	}
	"
	HAVE_DECL_STRERROR_S)

	# Check if 128-bit float computations can be done via long double.
	check_cxx_source_compiles(
	"#include <cfloat>
	#if LDBL_MANT_DIG != 113
	#error LDBL_MANT_DIG != 113
	#endif
	int main() { return 0; }
	"
	HAVE_LDBL_MANT_DIG_113)

	check_cxx_compiler_flag(-fno-lto FLANG_RUNTIME_HAS_FNO_LTO_FLAG)
	if (FLANG_RUNTIME_HAS_FNO_LTO_FLAG)
	set(NO_LTO_FLAGS "-fno-lto")
	else()
	set(NO_LTO_FLAGS "")
	endif()

	configure_file(config.h.cmake config.h)
	# include_directories is used here instead of target_include_directories
	# because add_flang_library creates multiple objects (STATIC/SHARED, OBJECT)
	# with different names
	include_directories(AFTER ${CMAKE_CURRENT_BINARY_DIR})

	append(${NO_LTO_FLAGS} CMAKE_C_FLAGS)
	append(${NO_LTO_FLAGS} CMAKE_CXX_FLAGS)

	# Disable libstdc++/libc++ assertions, even in an LLVM_ENABLE_ASSERTIONS build,
	# to avoid an unwanted dependency on libstdc++/libc++.so.
	add_definitions(-U_GLIBCXX_ASSERTIONS)
	add_definitions(-U_LIBCPP_ENABLE_ASSERTIONS)

	add_subdirectory(FortranMain)
	add_subdirectory(Float128Math)

	set(sources
	ISO_Fortran_binding.cpp
	allocatable.cpp
	array-constructor.cpp
	assign.cpp
	buffer.cpp
	character.cpp
	command.cpp
	complex-powi.cpp
	complex-reduction.c
	connection.cpp
	copy.cpp
	derived-api.cpp
	derived.cpp
	descriptor-io.cpp
	descriptor.cpp
	dot-product.cpp
	edit-input.cpp
	edit-output.cpp
	environment.cpp
	exceptions.cpp
	execute.cpp
	extensions.cpp
	external-unit.cpp
	extrema.cpp
	file.cpp
	findloc.cpp
	format.cpp
	inquiry.cpp
	internal-unit.cpp
	io-api.cpp
	io-error.cpp
	io-stmt.cpp
	iostat.cpp
	main.cpp
	matmul-transpose.cpp
	matmul.cpp
	memory.cpp
	misc-intrinsic.cpp
	namelist.cpp
	non-tbp-dio.cpp
	numeric.cpp
	pointer.cpp
	product.cpp
	pseudo-unit.cpp
	ragged.cpp
	random.cpp
	reduce.cpp
	reduction.cpp
	stat.cpp
	stop.cpp
	sum.cpp
	support.cpp
	temporary-stack.cpp
	terminator.cpp
	time-intrinsic.cpp
	tools.cpp
	transformational.cpp
	type-code.cpp
	type-info.cpp
	unit-map.cpp
	unit.cpp
	utf.cpp
	)

	option(FLANG_EXPERIMENTAL_CUDA_RUNTIME
	"Compile Fortran runtime as CUDA sources (experimental)" OFF
	)
	set(FLANG_LIBCUDACXX_PATH "" CACHE PATH "Path to libcu++ package installation")

	# List of files that are buildable for all devices.
	set(supported_files
	ISO_Fortran_binding.cpp
	allocatable.cpp
	array-constructor.cpp
	assign.cpp
	buffer.cpp
	character.cpp
	connection.cpp
	copy.cpp
	derived-api.cpp
	derived.cpp
	descriptor.cpp
	descriptor-io.cpp
	dot-product.cpp
	edit-input.cpp
	edit-output.cpp
	environment.cpp
	extrema.cpp
	external-unit.cpp
	findloc.cpp
	format.cpp
	inquiry.cpp
	internal-unit.cpp
	io-api.cpp
	io-error.cpp
	io-stmt.cpp
	iostat.cpp
	matmul-transpose.cpp
	matmul.cpp
	memory.cpp
	misc-intrinsic.cpp
	namelist.cpp
	non-tbp-dio.cpp
	numeric.cpp
	pointer.cpp
	product.cpp
	pseudo-unit.cpp
	ragged.cpp
	stat.cpp
	sum.cpp
	support.cpp
	terminator.cpp
	tools.cpp
	transformational.cpp
	type-code.cpp
	type-info.cpp
	unit.cpp
	utf.cpp
	)

	if (FLANG_EXPERIMENTAL_CUDA_RUNTIME)
	if (BUILD_SHARED_LIBS)
	message(FATAL_ERROR
	"BUILD_SHARED_LIBS is not supported for CUDA build of Fortran runtime"
	)
	endif()

	enable_language(CUDA)

	# TODO: figure out how to make target property CUDA_SEPARABLE_COMPILATION
	# work, and avoid setting CMAKE_CUDA_SEPARABLE_COMPILATION.
	set(CMAKE_CUDA_SEPARABLE_COMPILATION ON)

	# Treat all supported sources as CUDA files.
	set_source_files_properties(${supported_files} PROPERTIES LANGUAGE CUDA)
	set(CUDA_COMPILE_OPTIONS)
	if ("${CMAKE_CUDA_COMPILER_ID}" MATCHES "Clang")
	# Allow varargs.
	set(CUDA_COMPILE_OPTIONS
	-Xclang -fcuda-allow-variadic-functions
	)
	endif()
	if ("${CMAKE_CUDA_COMPILER_ID}" MATCHES "NVIDIA")
	set(CUDA_COMPILE_OPTIONS
	--expt-relaxed-constexpr
	# Disable these warnings:
	# 'long double' is treated as 'double' in device code
	-Xcudafe --diag_suppress=20208
	-Xcudafe --display_error_number
	)
	endif()
	set_source_files_properties(${supported_files} PROPERTIES COMPILE_OPTIONS
	"${CUDA_COMPILE_OPTIONS}"
	)

	if (EXISTS "${FLANG_LIBCUDACXX_PATH}/include")
	# When using libcudacxx headers files, we have to use them
	# for all files of F18 runtime.
	include_directories(AFTER ${FLANG_LIBCUDACXX_PATH}/include)
	add_compile_definitions(RT_USE_LIBCUDACXX=1)
	endif()
	endif()

	set(FLANG_EXPERIMENTAL_OMP_OFFLOAD_BUILD "off" CACHE STRING
	"Compile Fortran runtime as OpenMP target offload sources (experimental). Valid options are 'off', 'host_device', 'nohost'")

	set(FLANG_OMP_DEVICE_ARCHITECTURES "all" CACHE STRING
	"List of OpenMP device architectures to be used to compile the Fortran runtime (e.g. 'gfx1103;sm_90')")

	if (NOT FLANG_EXPERIMENTAL_OMP_OFFLOAD_BUILD STREQUAL "off")
	# 'host_device' build only works with Clang compiler currently.
	# The build is done with the CMAKE_C/CXX_COMPILER, i.e. it does not use
	# the in-tree built Clang. We may have a mode that would use the in-tree
	# built Clang.
	#
	# 'nohost' is supposed to produce an LLVM Bitcode library,
	# and it has to be done with a C/C++ compiler producing LLVM Bitcode
	# compatible with the LLVM toolchain version distributed with the Flang
	# compiler.
	# In general, the in-tree built Clang should be used for 'nohost' build.
	# Note that 'nohost' build does not produce the host version of Flang
	# runtime library, so there will be two separate distributable objects.
	# 'nohost' build is a TODO.

	if (NOT FLANG_EXPERIMENTAL_OMP_OFFLOAD_BUILD STREQUAL "host_device")
	message(FATAL_ERROR "Unsupported OpenMP offload build of Flang runtime")
	endif()
	if (BUILD_SHARED_LIBS)
	message(FATAL_ERROR
	"BUILD_SHARED_LIBS is not supported for OpenMP offload build of Fortran runtime"
	)
	endif()

	if ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" AND
	"${CMAKE_C_COMPILER_ID}" MATCHES "Clang")

	set(all_amdgpu_architectures
	"gfx700;gfx701;gfx801;gfx803;gfx900;gfx902;gfx906"
	"gfx908;gfx90a;gfx90c;gfx940;gfx1010;gfx1030"
	"gfx1031;gfx1032;gfx1033;gfx1034;gfx1035;gfx1036"
	"gfx1100;gfx1101;gfx1102;gfx1103;gfx1150;gfx1151"
	)
	set(all_nvptx_architectures
	"sm_35;sm_37;sm_50;sm_52;sm_53;sm_60;sm_61;sm_62"
	"sm_70;sm_72;sm_75;sm_80;sm_86;sm_89;sm_90"
	)
	set(all_gpu_architectures
	"${all_amdgpu_architectures};${all_nvptx_architectures}"
	)
	# TODO: support auto detection on the build system.
	if (FLANG_OMP_DEVICE_ARCHITECTURES STREQUAL "all")
	set(FLANG_OMP_DEVICE_ARCHITECTURES ${all_gpu_architectures})
	endif()
	list(REMOVE_DUPLICATES FLANG_OMP_DEVICE_ARCHITECTURES)

	string(REPLACE ";" "," compile_for_architectures
	"${FLANG_OMP_DEVICE_ARCHITECTURES}"
	)

	set(OMP_COMPILE_OPTIONS
	-fopenmp
	-fvisibility=hidden
	-fopenmp-cuda-mode
	--offload-arch=${compile_for_architectures}
	# Force LTO for the device part.
	-foffload-lto
	)
	set_source_files_properties(${supported_files} PROPERTIES COMPILE_OPTIONS
	"${OMP_COMPILE_OPTIONS}"
	)

	# Enable "declare target" in the source code.
	set_source_files_properties(${supported_files}
	PROPERTIES COMPILE_DEFINITIONS OMP_OFFLOAD_BUILD
	)
	else()
	message(FATAL_ERROR
	"Flang runtime build is not supported for these compilers:\n"
	"CMAKE_CXX_COMPILER_ID: ${CMAKE_CXX_COMPILER_ID}\n"
	"CMAKE_C_COMPILER_ID: ${CMAKE_C_COMPILER_ID}")
	endif()
	endif()

	if (NOT TARGET FortranFloat128Math)
	# If FortranFloat128Math is not defined, then we are not building
	# standalone FortranFloat128Math library. Instead, include
	# the relevant sources into FortranRuntime itself.
	# The information is provided via FortranFloat128MathILib
	# interface library.
	get_target_property(f128_sources
	FortranFloat128MathILib INTERFACE_SOURCES
	)
	if (f128_sources)
	# The interface may define special macros for Float128Math files,
	# so we need to propagate them.
	get_target_property(f128_defs
	FortranFloat128MathILib INTERFACE_COMPILE_DEFINITIONS
	)
	set_property(SOURCE ${f128_sources}
	APPEND PROPERTY COMPILE_DEFINITIONS
	${f128_defs}
	)
	list(APPEND sources ${f128_sources})
	endif()
	endif()

	if (NOT DEFINED MSVC)
	add_flang_library(FortranRuntime
	${sources}
	LINK_LIBS
	FortranDecimal

	INSTALL_WITH_TOOLCHAIN
	)
	else()
	add_flang_library(FortranRuntime
	${sources}
	LINK_LIBS
	FortranDecimal
	)
	set(CMAKE_MSVC_RUNTIME_LIBRARY MultiThreaded)
	add_flang_library(FortranRuntime.static ${sources}
	LINK_LIBS
	FortranDecimal.static
	INSTALL_WITH_TOOLCHAIN)
	set(CMAKE_MSVC_RUNTIME_LIBRARY MultiThreadedDLL)
	add_flang_library(FortranRuntime.dynamic ${sources}
	LINK_LIBS
	FortranDecimal.dynamic
	INSTALL_WITH_TOOLCHAIN)
	set(CMAKE_MSVC_RUNTIME_LIBRARY MultiThreadedDebug)
	add_flang_library(FortranRuntime.static_dbg ${sources}
	LINK_LIBS
	FortranDecimal.static_dbg
	INSTALL_WITH_TOOLCHAIN)
	set(CMAKE_MSVC_RUNTIME_LIBRARY MultiThreadedDebugDLL)
	add_flang_library(FortranRuntime.dynamic_dbg ${sources}
	LINK_LIBS
	FortranDecimal.dynamic_dbg
	INSTALL_WITH_TOOLCHAIN)
	add_dependencies(FortranRuntime FortranRuntime.static FortranRuntime.dynamic
	FortranRuntime.static_dbg FortranRuntime.dynamic_dbg)
	endif()