Introduce rules_rust_unsupported_feature (#2511)
Add a special sentinel feature name to the UNSUPPORTED_FEATURES list.
This feature name can be used by authors of C++ toolchain configurations
to house any configuration fragments (e.g., linker flags) that should
NOT be applied when linking Rust targets.
The specific motivation for this is that I'm working on a project that
includes `-fsanitize=address` in its clang configuration. This needs to
be disabled when linking Rust.
I tried the more straightforward approach of adding the `features`
attribute to `rust_binary` targets in my repo, but this is not
sufficient: a `rust_binary` has implicit deps on targets like
@rules_rust//util/process_wrapper:bootstrap_process_wrapper.
diff --git a/rust/private/utils.bzl b/rust/private/utils.bzl
index 748370d..783aa22 100644
--- a/rust/private/utils.bzl
+++ b/rust/private/utils.bzl
@@ -24,6 +24,10 @@
"use_header_modules",
"fdo_instrument",
"fdo_optimize",
+ # This feature is unsupported by definition. The authors of C++ toolchain
+ # configuration can place any linker flags that should not be applied when
+ # linking Rust targets in a feature with this name.
+ "rules_rust_unsupported_feature",
]
def find_toolchain(ctx):
