🍒[cxx-interop] Lower macOS deployment target version for the Cxx module #69605
Conversation
The CMake flag `DEPLOYMENT_VERSION_OSX` is currently only passed to the C compiler. This change makes sure it is also passed to the Swift compiler, e.g. when building Swift-only targets like Cxx or CxxStdlib. rdar://117699474 (cherry picked from commit e192ee2)
The Cxx module does not rely on any modern OS features. It can be deployed to older macOS versions. rdar://117699474 (cherry picked from commit 00cdb66)
|
@swift-ci please test |
| @@ -23,6 +23,8 @@ add_swift_target_library(swiftCxx STATIC NO_LINK_NAME IS_STDLIB IS_SWIFT_ONLY IS | |||
| # For functionality that depends on the C++ stdlib, use C++ stdlib overlay (`swiftstd` module). | |||
| -Xcc -nostdinc++ | |||
|
|
|||
| DEPLOYMENT_VERSION_OSX ${COMPATIBILITY_MINIMUM_DEPLOYMENT_VERSION_OSX} | |||
There was a problem hiding this comment.
It seems like this needs to be done for all Apple OS's, as we do for the various compatibility libraries, e.g.,
DEPLOYMENT_VERSION_OSX ${COMPATIBILITY_MINIMUM_DEPLOYMENT_VERSION_OSX}
DEPLOYMENT_VERSION_IOS ${COMPATIBILITY_MINIMUM_DEPLOYMENT_VERSION_IOS}
DEPLOYMENT_VERSION_TVOS ${COMPATIBILITY_MINIMUM_DEPLOYMENT_VERSION_TVOS}
DEPLOYMENT_VERSION_WATCHOS ${COMPATIBILITY_MINIMUM_DEPLOYMENT_VERSION_WATCHOS}
MACCATALYST_BUILD_FLAVOR "zippered"
There was a problem hiding this comment.
Done, I added other Apple platforms here
| @@ -49,6 +49,8 @@ add_swift_target_library(swiftCxxStdlib STATIC NO_LINK_NAME IS_STDLIB IS_SWIFT_O | |||
| SWIFT_COMPILE_FLAGS_LINUX | |||
| ${SWIFT_SDK_LINUX_CXX_OVERLAY_SWIFT_COMPILE_FLAGS} | |||
|
|
|||
| DEPLOYMENT_VERSION_OSX ${COMPATIBILITY_MINIMUM_DEPLOYMENT_VERSION_OSX} | |||
There was a problem hiding this comment.
Same comment here about all Apple platforms
| @@ -452,6 +457,7 @@ function(_compile_swift_files | |||
| "${SWIFT_STDLIB_BUILD_TYPE}" | |||
| "${SWIFT_STDLIB_ASSERTIONS}" | |||
| swift_flags | |||
| DEPLOYMENT_VERSION_OSX ${SWIFTFILE_DEPLOYMENT_VERSION_OSX} | |||
There was a problem hiding this comment.
I'm surprised that any of these changes are needed, given that add_swift_target_library is already being used with these DEPLOYMENT_VERSION_* options elsewhere. Are you sure these changes here are necessary?
There was a problem hiding this comment.
add_swift_target_library currently only applies these options for C/C++ source files. Here we're making it apply DEPLOYMENT_VERSION_* for Swift modules as well.
|
@swift-ci please test |
Explanation: The Cxx module does not rely on any modern OS features. It can be deployed to older macOS versions. Having a high deployment target blocks certain usage workflows of the Cxx module.
Scope: All of the code changes are on a C++ interop only code path.
Risk: Low, only takes effect when C++ interop is enabled.
Testing: Covered by LIT tests.
Original PR: #69512
rdar://117699474