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| author | Alexandru Croitor <alexandru.croitor@qt.io> | 2021-04-13 18:57:07 +0200 |
|---|---|---|
| committer | Qt Cherry-pick Bot <cherrypick_bot@qt-project.org> | 2021-04-19 20:13:58 +0000 |
| commit | 93dbd93809656259b1e30576182814572bb86204 (patch) | |
| tree | 6826897c75d16de0a3abbe211aba402260721e09 /cmake | |
| parent | 3cdcb53a37bbdbd42f5da2b22d3adeba3cd9ed9a (diff) | |
CMake: Introduce zlib find script to work around hardcoded iOS SDK
Xcode allows building a project targeting either the device or
simulator sysroot in one single build dir, but for the sysroot
switching to work there should be no linker or compiler flags
referencing absolute paths of a specific sysroot.
During CMake configuration of a project targeting iOS, all found
system libraries will be within one single sysroot, either the device
one or the simulator one, whichever one was passed to
CMAKE_OSX_SYSROOT. CMake will then generate the Xcode project
and pass those absolute paths, which makes sysroot switching within
Xcode not work.
To avoid that, the CMake documentation recommends passing linker and
framework flags of the form '-lfoo' and '-framework bar' instead of
absolute paths. Xcode then takes care of setting the correct framework
search path.
Zlib is one of the libraries found in the iOS sysroot and thus passed
as absolute path.
To avoid that, create a new FindWrapZLIB find script. The target it
creates will pass the absolute path to the library on non Apple
platforms and an -lz linker flag on Apple platforms (macOS and iOS).
To avoid issues with target global promotion when system PNG package
is found, ensure that a found ZLIB::ZLIB target is promoted to global
manually in src/gui/configure.cmake.
Change-Id: I8bd8649be4f680a331ad51925f27cb9d13ac5e5f
Reviewed-by: Cristian Adam <cristian.adam@qt.io>
(cherry picked from commit b25eb6e0bd1e3b91c44dc4892d529b95c8677889)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
Diffstat (limited to 'cmake')
| -rw-r--r-- | cmake/FindWrapZLIB.cmake | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/cmake/FindWrapZLIB.cmake b/cmake/FindWrapZLIB.cmake new file mode 100644 index 0000000000..585dc5e95e --- /dev/null +++ b/cmake/FindWrapZLIB.cmake @@ -0,0 +1,29 @@ +# We can't create the same interface imported target multiple times, CMake will complain if we do +# that. This can happen if the find_package call is done in multiple different subdirectories. +if(TARGET WrapZLIB::WrapZLIB) + set(WrapZLIB_FOUND ON) + return() +endif() + +set(WrapZLIB_FOUND OFF) + +find_package(ZLIB ${WrapZLIB_FIND_VERSION}) + +if(ZLIB_FOUND) + set(WrapZLIB_FOUND ON) + + add_library(WrapZLIB::WrapZLIB INTERFACE IMPORTED) + if(APPLE) + # On Darwin platforms FindZLIB sets IMPORTED_LOCATION to the absolute path of the library + # within the framework. This ends up as an absolute path link flag, which we don't want, + # because that makes our .prl files un-relocatable and also breaks iOS simulator_and_device + # SDK switching in Xcode. + # Just pass a linker flag instead. + target_link_libraries(WrapZLIB::WrapZLIB INTERFACE "-lz") + else() + target_link_libraries(WrapZLIB::WrapZLIB INTERFACE ZLIB::ZLIB) + endif() +endif() + +include(FindPackageHandleStandardArgs) +find_package_handle_standard_args(WrapZLIB DEFAULT_MSG WrapZLIB_FOUND) |