CheckIncludeFiles
Provides a macro to check if a list of one or more header files can be included together.
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CHECK_INCLUDE_FILES - 
CHECK_INCLUDE_FILES("<includes>" <variable> [LANGUAGE <language>])Check if the given
<includes>list may be included together in a source file and store the result in an internal cache entry named<variable>. Specify the<includes>argument as a ;-list of header file names. 
If LANGUAGE is set, the specified compiler will be used to perform the check. Acceptable values are C and CXX. If not set, the C compiler will be used if enabled. If the C compiler is not enabled, the C++ compiler will be used if enabled.
The following variables may be set before calling this macro to modify the way the check is run:
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CMAKE_REQUIRED_FLAGS - string of compile command line flags
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CMAKE_REQUIRED_DEFINITIONS - list of macros to define (-DFOO=bar)
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CMAKE_REQUIRED_INCLUDES - list of include directories
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CMAKE_REQUIRED_LIBRARIES - A list of libraries to link. See policy 
CMP0075. - 
CMAKE_REQUIRED_QUIET - execute quietly without messages
 
See modules CheckIncludeFile and CheckIncludeFileCXX to check for a single header file in C or CXX languages.
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Licensed under the BSD 3-clause License.
    https://cmake.org/cmake/help/v3.12/module/CheckIncludeFiles.html