···11+macro( MACRO_ENSURE_OUT_OF_SOURCE_BUILD )
22+string( COMPARE EQUAL "${CMAKE_SOURCE_DIR}" "${CMAKE_BINARY_DIR}" _insource )
33+if( _insource )
44+ message( FATAL_ERROR
55+ "In-source builds are not allowed.
66+ CMake would overwrite the Linux kernel module Makefile.
77+ Please create a directory and run cmake from there, passing the path
88+ to this source directory as the last argument.
99+ This process created the file `CMakeCache.txt' and the directory `CMakeFiles'.
1010+ Please delete them."
1111+ )
1212+endif( _insource )
1313+endmacro( MACRO_ENSURE_OUT_OF_SOURCE_BUILD )
1414+