Adds an uninstall target to the CMAKE generated Makefile.

CMakeLists.txt

##
# Add uninstall target
# Requirements: Copy the uninstall.cmake file to the appropriate CMAKE_MODULE_PATH.
#

add_custom_target(uninstall
    "${CMAKE_COMMAND}" -P "${CMAKE_MODULE_PATH}/uninstall.cmake"
)

uninstall.cmake

set(MANIFEST "${CMAKE_CURRENT_BINARY_DIR}/install_manifest.txt")

if(NOT EXISTS ${MANIFEST})
    message(FATAL_ERROR "Cannot find install manifest: '${MANIFEST}'")
endif()

file(STRINGS ${MANIFEST} files)
foreach(file ${files})
    if(EXISTS ${file})
        message(STATUS "Removing file: '${file}'")

        exec_program(
            ${CMAKE_COMMAND} ARGS "-E remove ${file}"
            OUTPUT_VARIABLE stdout
            RETURN_VALUE result
        )
        
        if(NOT "${result}" STREQUAL 0)
            message(FATAL_ERROR "Failed to remove file: '${file}'.")
        endif()
    else()
        MESSAGE(STATUS "File '${file}' does not exist.")
    endif()
endforeach(file)

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