when passing -platform_version to the linker
The use of a valid SDK version is preferred over an empty SDK version
(0.0.0) as the system's runtime might expect the linked binary to contain
a valid SDK version in order for the binary to work correctly
rdar://66795188
Fix regression where we aren't passing `-platform_version` to new ld64.lld after {D95204}.
Most of the changes were originally in D95204, but I backed them out due to
test failures on builds which have `CLANG_DEFAULT_LINKER=lld`. The tests are
properly updated in this diff.
Reviewed By: #lld-macho, thakis
Differential Revision: https://reviews.llvm.org/D97741
The new Darwin backend for LLD is now able to link reasonably large
real-world programs on x86_64. For instance, we have achieved
self-hosting for the X86_64 target, where all LLD tests pass when
building lld with itself on macOS. As such, we would like to make it the
default back-end.
The new port is now named `ld64.lld`, and the old port remains
accessible as `ld64.lld.darwinold`
This [annoucement email][1] has some context. (But note that, unlike
what the email says, we are no longer doing this as part of the LLVM 12
branch cut -- instead we will go into LLVM 13.)
Numerous mechanical test changes were required to make this change; in
the interest of creating something that's reviewable on Phabricator,
I've split out the boring changes into a separate diff (D95905). I plan to
merge its contents with those in this diff before landing.
(@gkm made the original draft of this diff, and he has agreed to let me
take over.)
[1]: https://lists.llvm.org/pipermail/llvm-dev/2021-January/147665.html
Reviewed By: #lld-macho, thakis
Differential Revision: https://reviews.llvm.org/D95204
New MachO LLD doesn't implement the old -macos_version_min (etc)
flags, but it understands the modern platform_version flag.
So make the clang driver pass that when using new MachO LLD.
Also, while here, don't pass -lto_library to LLD, since it
links in LTO libraries statically (which it can because it's
versioned alongside clang).
Differential Revision: https://reviews.llvm.org/D92037
if it's newer than the target version
This change ensures that the arm64-apple-macOS slice is linked for
macOS 11 even if the deployment target is earlier than macOS 11.
The code in llvmorg-10-init-12188-g25ce33a6e4f is a breaking change for
users of older linkers who don't pass a version parameter, which
prevents a drop-in clang upgrade. Old tools can't know about what future
tools will do, so as a general principle the burden should be new tools
to be compatible by default. Also, for comparison, none of the other
tests of Version within AddLinkArgs add any new behaviors unless the
version is explicitly specified. Therefore, this patch changes the
-platform_version behavior from opt-out to opt-in.
Patch by David Major!
Differential revision: https://reviews.llvm.org/D74784
The driver actually adds a default -mlinker-version, based on HOST_LINK_VERSION
cmake variable. The tests should be explicit about which version they're using to
trigger the right behavior.
In Xcode 11, ld added a new flag called -platform_version that can be used instead of the old -<platform>_version_min flags.
The new flag allows Clang to pass the SDK version from the driver to the linker.
This patch adopts the new -platform_version flag in Clang, and starts using it by default,
unless a linker version < 520 is passed to the driver.
Differential Revision: https://reviews.llvm.org/D71579