mirror of
https://github.com/reactos/CMake.git
synced 2024-12-05 02:06:34 +00:00
f266182aec
Fixes: #18521
86 lines
2.9 KiB
CMake
86 lines
2.9 KiB
CMake
# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
|
|
# file Copyright.txt or https://cmake.org/licensing for details.
|
|
|
|
#[=======================================================================[.rst:
|
|
CheckVariableExists
|
|
-------------------
|
|
|
|
Check if the variable exists.
|
|
|
|
.. command:: CHECK_VARIABLE_EXISTS
|
|
|
|
.. code-block:: cmake
|
|
|
|
CHECK_VARIABLE_EXISTS(VAR VARIABLE)
|
|
|
|
|
|
::
|
|
|
|
VAR - the name of the variable
|
|
VARIABLE - variable to store the result
|
|
Will be created as an internal cache variable.
|
|
|
|
|
|
This macro is only for ``C`` variables.
|
|
|
|
The following variables may be set before calling this macro to modify
|
|
the way the check is run:
|
|
|
|
::
|
|
|
|
CMAKE_REQUIRED_FLAGS = string of compile command line flags
|
|
CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar)
|
|
CMAKE_REQUIRED_LINK_OPTIONS = list of options to pass to link command
|
|
CMAKE_REQUIRED_LIBRARIES = list of libraries to link
|
|
CMAKE_REQUIRED_QUIET = execute quietly without messages
|
|
#]=======================================================================]
|
|
|
|
include_guard(GLOBAL)
|
|
|
|
macro(CHECK_VARIABLE_EXISTS VAR VARIABLE)
|
|
if(NOT DEFINED "${VARIABLE}")
|
|
set(MACRO_CHECK_VARIABLE_DEFINITIONS
|
|
"-DCHECK_VARIABLE_EXISTS=${VAR} ${CMAKE_REQUIRED_FLAGS}")
|
|
if(NOT CMAKE_REQUIRED_QUIET)
|
|
message(STATUS "Looking for ${VAR}")
|
|
endif()
|
|
if(CMAKE_REQUIRED_LINK_OPTIONS)
|
|
set(CHECK_VARIABLE_EXISTS_ADD_LINK_OPTIONS
|
|
LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
|
|
else()
|
|
set(CHECK_VARIABLE_EXISTS_ADD_LINK_OPTIONS)
|
|
endif()
|
|
if(CMAKE_REQUIRED_LIBRARIES)
|
|
set(CHECK_VARIABLE_EXISTS_ADD_LIBRARIES
|
|
LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
|
|
else()
|
|
set(CHECK_VARIABLE_EXISTS_ADD_LIBRARIES)
|
|
endif()
|
|
try_compile(${VARIABLE}
|
|
${CMAKE_BINARY_DIR}
|
|
${CMAKE_ROOT}/Modules/CheckVariableExists.c
|
|
COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
|
|
${CHECK_VARIABLE_EXISTS_ADD_LINK_OPTIONS}
|
|
${CHECK_VARIABLE_EXISTS_ADD_LIBRARIES}
|
|
CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_VARIABLE_DEFINITIONS}
|
|
OUTPUT_VARIABLE OUTPUT)
|
|
if(${VARIABLE})
|
|
set(${VARIABLE} 1 CACHE INTERNAL "Have variable ${VAR}")
|
|
if(NOT CMAKE_REQUIRED_QUIET)
|
|
message(STATUS "Looking for ${VAR} - found")
|
|
endif()
|
|
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
|
|
"Determining if the variable ${VAR} exists passed with the following output:\n"
|
|
"${OUTPUT}\n\n")
|
|
else()
|
|
set(${VARIABLE} "" CACHE INTERNAL "Have variable ${VAR}")
|
|
if(NOT CMAKE_REQUIRED_QUIET)
|
|
message(STATUS "Looking for ${VAR} - not found")
|
|
endif()
|
|
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
|
|
"Determining if the variable ${VAR} exists failed with the following output:\n"
|
|
"${OUTPUT}\n\n")
|
|
endif()
|
|
endif()
|
|
endmacro()
|