For policy-specific tests, use the version before the policy was
introduced. Otherwise, use 3.5 where possible.
Also, remove `cmake_minimum_required()` and `project()` calls from
individual cases where they are handled by `CMakeLists.txt`.
Ensure that we're actually trying to rebuild libB when the public
interface for libA changes. Without handling the swiftmodule dependency
edge correctly, we would only get a linker error because libA didn't
have the symbol that libB depended on. With the fix, we get a proper
compiler error because ninja knows to rebuild the intermediate libB
when the public interface of libA changes. This is more actionable.
This patch adds support for tracking the swiftmodules for executables
exporting symbols.
This fixes a bug in the earlier implementation around emitting the
swiftmodule. Previously, the code would use
`CMAKE_EXE_EXPORTS_Swift_FLAG` to inject the `-emit-module`, and module
path information into the `CMAKE_Swift_LINK_EXECUTABLE` rule. Because
Swift skips the build step and only runs during the link phase, these
flags were injected in `cmNinjaNormalTargetGenerator::ComputeLinkCmd`
instead of `cmLocalGenerator::GetTargetFlags` where it is done normally.
Unfortunately, injecting in `ComputeLinkCmd` didn't do anything because
we have a `linkCmd` so `ComputeLinkCmd` exits early, before the
EXE_EXPORT flags get added to the link command.
Instead of playing with that flag, CMake checks
`CMAKE_Swift_LINK_EXECUTABLE_WITH_EXPORTS` and uses that as the link
rule if it exists and falls back on `CMAKE_Swift_LINK_EXECUTABLE`. I've
defined that variable in terms of `CMAKE_Swift_LINK_EXECUTABLE` with the
necessary additional flags for emitting the swift module instead. This
has the same end effect as the desired behavior, but simplifies things a
bit.
Since we're generating the swiftmodule for executables with exports,
I've also updated the dependency graph to include the swiftmodule as an
output in the build dependency graph if the executable has exports.
Tests updated:
- RunCMake/NoWorkToDo:
Ensure that the build graph does not result in unnecessary rebuilds
with exporting executables.
- SwiftOnly:
Ensure that we can consume functions defined in the executable by a
library getting linked into said executable.
Swift doesn't emit swiftmodules for executables, so we shouldn't put it
in dependency graph. Ninja sees the "missing" dependency and always
tries to rebuild/re-link the target.
Currently, the compiler does not synthesize the correct entry point for
the application and passing the subsystem flag does not work the same
way with the Swift linker language. Add a check to prevent the
application of `WIN32_EXECUTABLE` to Swift executables until they can be
properly supported. This will prevent the need for a future policy
change.
Closes: #19325
It's relatively complex to determine in advance if a Xcode, SDK,
and Deployment Target configuration is capable of running Swift.
For example the following combinations do not work:
* deployment target < OS X 10.9
* Xcode 6.2 and macosx10.9 SDK
* Xcode 7 Beta 6 and macosx10.10 SDK
Until we found out how to query Xcode for Swift support in a reliable
way, the RunCMake.Swift test cases will be restricted to negative ones.
Allow the `Swift` language to be enabled with the Xcode generator for
Xcode >= 6.1. Reject it on other generators and with older Xcode
versions. Since Apple is the only vendor implementing the language
right now, the compiler id can be just `Apple`.
