############################################################################
#
#   Copyright (c) 2019 PX4 Development Team. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in
#    the documentation and/or other materials provided with the
#    distribution.
# 3. Neither the name PX4 nor the names of its contributors may be
#    used to endorse or promote products derived from this software
#    without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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############################################################################

# ccache

option(CCACHE "Use ccache if available" ON)
find_program(CCACHE_PROGRAM ccache)
if(CCACHE AND CCACHE_PROGRAM AND NOT DEFINED ENV{CCACHE_DISABLE})
	get_filename_component(ccache_real_path ${CCACHE_PROGRAM} REALPATH)
	get_filename_component(cxx_real_path ${CMAKE_CXX_COMPILER} REALPATH)
	get_filename_component(cxx_abs_path ${CMAKE_CXX_COMPILER} ABSOLUTE)

	if ("${ccache_real_path}" STREQUAL "${cxx_real_path}")
		message(STATUS "ccache enabled via symlink (${cxx_abs_path} -> ${cxx_real_path})")
		set(CCACHE_PROGRAM "" CACHE INTERNAL "ccache program" FORCE)
	else()
		message(STATUS "ccache enabled (export CCACHE_DISABLE=1 to disable)")
		set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE "${CCACHE_PROGRAM}")
	endif()
else()
	set(CCACHE_PROGRAM "" CACHE INTERNAL "ccache program" FORCE)
endif()