Since CMake 3.19, we no longer support macOS SDKs older than 10.5,
which corresponds to Xcode 3. Supporting older Xcode versions for
device platforms is also not realistic. We therefore expect the -rpath
linker option should always be supported now.
When targeting iOS, tvOS or watchOS, the previous disabling of -rpath
support meant that the install_name_dir of shared libraries and
frameworks was unable to use @rpath. This resulted in embedding
absolute paths for their install_name. When they were embedded in an
app bundle, this would cause the app to fail at runtime. By enabling the
-rpath linker option, the default install_name_dir is now @rpath for these platforms, which results in binaries that do work at runtime.
Fixes: #20036
Since commit c30d06b7e6 (FindIntl: Add imported target, 2020-10-06,
v3.20.0-rc1~687^2) we use `check_symbol_exists` to check whether the
`intl` library is built in to the C library. On some platforms the
tested symbols are provided as macros so the check passes without
linking any symbol. Instead, check whether a sample source file both
compiles and links.
Fixes: #21979
Refactoring of the ExternalProject and FetchContent modules moved
the commands into CMake scripts. This broke custom commands that
used shell redirection or special build tool variables of the form
$(MakeVar). Undo the sequence of commits that performed this
refactoring and follow-up fixes associated with it.
The following commits are reverted by this change:
4f3d1abbb4 (ExternalProject: Refactor pre-configure steps to support
no-target uses, 2021-02-05)
17e5516e60 (FetchContent: Invoke steps directly and avoid a separate
sub-build, 2021-01-29)
bd876f3849 (FetchContent: Restore patch command support,
2021-02-18)
404cddb7bb (ExternalProject: Fix misuse of IS_NEWER_THAN in
timestamp checks, 2021-02-21)
b0da671243 (FetchContent: Don't update timestamps if files don't
change, 2021-02-18)
Fixes: #21892
