Upstreams:

-
ed48510
-
7400308

…et_current_xcode` helpers (#408)

…t methods to resolve constraints to return None rather than fail when a constraint is not found. (#410)

Upstreams:
07f7876

Upstreams:
436b03d

---------

Co-authored-by: Tony Allevato <allevato@google.com>

This will be used as the `//conditions:default` choice for the
`xcode_version.sdk` attribute, ensuring that non-configured
builds/queries don't fail early if they just happen to graze one of the
Xcode targets.

PiperOrigin-RevId: 726034982

And:

PiperOrigin-RevId: 725333279

---------

Co-authored-by: Tony Allevato <allevato@google.com>

We here address the following obstacles in `apple_support` to using
Bazel's
`--incompatible_disable_target_default_provider_fields` flag:

ERROR:
/private/var/tmp/_bazel_dws/7fd3cd5077fbf76d9e2ae421c39ef7ed/external/apple_support+/crosstool/BUILD:25:20:
in apple_genrule rule
@@apple_support+//crosstool:exec_wrapped_clang_pp.target_config:
    Traceback (most recent call last):
File
"/private/var/tmp/_bazel_dws/7fd3cd5077fbf76d9e2ae421c39ef7ed/external/apple_support+/rules/private/apple_genrule.bzl",
line 52, column 45, in _apple_genrule_impl
resolved_srcs = depset(transitive = [dep.files for dep in
ctx.attr.srcs])
Error: Accessing the default provider in this manner is deprecated and
will be removed soon. It may be temporarily re-enabled by setting
--incompatible_disable_target_default_provider_fields=false. See
bazelbuild/bazel#20183 for details.
ERROR:
/private/var/tmp/_bazel_dws/7fd3cd5077fbf76d9e2ae421c39ef7ed/external/apple_support+/crosstool/BUILD:25:20:
Analysis of target
'@@apple_support+//crosstool:exec_wrapped_clang_pp.target_config' failed
ERROR: Analysis of target '//src:bazel' failed; build aborted: Analysis
failed

ERROR:
/private/var/tmp/_bazel_dws/7fd3cd5077fbf76d9e2ae421c39ef7ed/external/apple_support++apple_cc_configure_extension+local_config_apple_cc/BUILD:78:24:
in cc_toolchain_config rule
@@apple_support++apple_cc_configure_extension+local_config_apple_cc//:darwin_x86_64:
    Traceback (most recent call last):
File
"/private/var/tmp/_bazel_dws/7fd3cd5077fbf76d9e2ae421c39ef7ed/external/apple_support++apple_cc_configure_extension+local_config_apple_cc/cc_toolchain_config.bzl",
line 2506, column 37, in _impl
                    modulemaps = ctx.attr.module_map.files.to_list()
Error: Accessing the default provider in this manner is deprecated and
will be removed soon. It may be temporarily re-enabled by setting
--incompatible_disable_target_default_provider_fields=false. See
bazelbuild/bazel#20183 for details.
ERROR:
/private/var/tmp/_bazel_dws/7fd3cd5077fbf76d9e2ae421c39ef7ed/external/apple_support++apple_cc_configure_extension+local_config_apple_cc/BUILD:78:24:
Analysis of target
'@@apple_support++apple_cc_configure_extension+local_config_apple_cc//:darwin_x86_64'
failed
ERROR: Analysis of target '//src:bazel' failed; build aborted: Analysis
failed

Required for compatibility with
bazelbuild/bazel#20183

In general one shouldn't call waitpid until the child closed its end of
the pipe. This works fine with libtool invocations that do not produce
more than `_PC_PIPE_BUF` bytes of output but deadlocks when the pipe
fills up.