CMakeLists: Require CMake version 3.1 or newer

Although CMake version 3.0.2 was previously required, the policies
CMP0053 and CMP0054, introduced only in CMake version 3.1 and used
in this CMakeLists file, can have surprising effects under an older
CMake version.

Simplify the CMakeLists file by setting the global policy version
to 3.1, and remove the specific policy settings.

As an added bonus, remove the vestigial workarounds for all ancient
CMake versions.
This commit is contained in:
Cosmin Truta 2018-11-17 23:39:15 -05:00
parent ee7967eea4
commit 7b2224cb6e

View File

@ -17,25 +17,8 @@
# For conditions of distribution and use, see the disclaimer
# and license in png.h
cmake_minimum_required(VERSION 3.0.2)
cmake_policy(VERSION 3.0.2)
# Set MacOSX @rpath usage globally.
if(POLICY CMP0020)
cmake_policy(SET CMP0020 NEW)
endif()
if(POLICY CMP0042)
cmake_policy(SET CMP0042 NEW)
endif()
# Use new variable expansion policy.
if(POLICY CMP0053)
cmake_policy(SET CMP0053 NEW)
endif()
if(POLICY CMP0054)
cmake_policy(SET CMP0054 NEW)
endif()
set(CMAKE_CONFIGURATION_TYPES "Release;Debug;MinSizeRel;RelWithDebInfo")
cmake_minimum_required(VERSION 3.1)
cmake_policy(VERSION 3.1)
project(libpng C ASM)
enable_testing()
@ -636,19 +619,11 @@ function(png_add_test)
configure_file("${CMAKE_CURRENT_SOURCE_DIR}/scripts/test.cmake.in"
"${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake" @ONLY)
if(CMAKE_MAJOR_VERSION GREATER 2) # have generator expressions
add_test(NAME "${_PAT_NAME}"
COMMAND "${CMAKE_COMMAND}"
"-DLIBPNG=$<TARGET_FILE:png>"
"-DTEST_COMMAND=$<TARGET_FILE:${_PAT_COMMAND}>"
-P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
else() # old 2.x add_test; limited and won't work well on Windows
# Note LIBPNG is a dummy value as there are no generator expressions
add_test("${_PAT_NAME}" "${CMAKE_COMMAND}"
"-DLIBPNG=${CMAKE_CURRENT_BINARY_DIR}/libpng.so"
"-DTEST_COMMAND=./${_PAT_COMMAND}"
-P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
endif()
endfunction()
if(PNG_TESTS AND PNG_SHARED)
@ -868,19 +843,10 @@ if(PNG_SHARED)
CLEAN_DIRECT_OUTPUT 1)
endif()
# If CMake > 2.4.x, we set a variable used below to export
# targets to an export file.
# TODO: Use VERSION_GREATER after our cmake_minimum_required >= 2.6.2
if(CMAKE_MAJOR_VERSION GREATER 1 AND CMAKE_MINOR_VERSION GREATER 4)
set(PNG_EXPORT_RULE EXPORT libpng)
elseif(CMAKE_MAJOR_VERSION GREATER 2) # future proof
set(PNG_EXPORT_RULE EXPORT libpng)
endif()
# INSTALL
if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL)
install(TARGETS ${PNG_LIB_TARGETS}
${PNG_EXPORT_RULE}
EXPORT libpng
RUNTIME DESTINATION bin
LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
@ -890,19 +856,22 @@ if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL)
# Create a symlink for libpng.dll.a => libpng16.dll.a on Cygwin
if(CYGWIN OR MINGW)
create_symlink(libpng${CMAKE_IMPORT_LIBRARY_SUFFIX} TARGET png)
install(FILES $<TARGET_LINKER_FILE_DIR:png>/libpng${CMAKE_IMPORT_LIBRARY_SUFFIX} DESTINATION ${CMAKE_INSTALL_LIBDIR})
install(FILES $<TARGET_LINKER_FILE_DIR:png>/libpng${CMAKE_IMPORT_LIBRARY_SUFFIX}
DESTINATION ${CMAKE_INSTALL_LIBDIR})
endif()
if(NOT WIN32)
create_symlink(libpng${CMAKE_SHARED_LIBRARY_SUFFIX} TARGET png)
install(FILES $<TARGET_LINKER_FILE_DIR:png>/libpng${CMAKE_SHARED_LIBRARY_SUFFIX} DESTINATION ${CMAKE_INSTALL_LIBDIR})
install(FILES $<TARGET_LINKER_FILE_DIR:png>/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}
DESTINATION ${CMAKE_INSTALL_LIBDIR})
endif()
endif()
if(PNG_STATIC)
if(NOT WIN32 OR CYGWIN OR MINGW)
create_symlink(libpng${CMAKE_STATIC_LIBRARY_SUFFIX} TARGET png_static)
install(FILES $<TARGET_LINKER_FILE_DIR:png_static>/libpng${CMAKE_STATIC_LIBRARY_SUFFIX} DESTINATION ${CMAKE_INSTALL_LIBDIR})
install(FILES $<TARGET_LINKER_FILE_DIR:png_static>/libpng${CMAKE_STATIC_LIBRARY_SUFFIX}
DESTINATION ${CMAKE_INSTALL_LIBDIR})
endif()
endif()
endif()
@ -943,9 +912,8 @@ if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL)
endif()
endif()
# On versions of CMake that support it, create an export file CMake
# users can include() to import our targets
if(PNG_EXPORT_RULE AND NOT SKIP_INSTALL_EXPORT AND NOT SKIP_INSTALL_ALL)
# Create an export file that CMake users can include() to import our targets.
if(NOT SKIP_INSTALL_EXPORT AND NOT SKIP_INSTALL_ALL)
install(EXPORT libpng DESTINATION lib/libpng FILE lib${PNG_LIB_NAME}.cmake)
endif()