C/C++ Rules Design & Bazel rules_cc Integration

Concise cc_shared_library Interface & Export Rules

• In cc_shared_library:
  • Targets directly placed in deps are automatically exported by Bazel; they do not need to be listed in exports_filter.
  • exports_filter is defined in rules_cc as an attr.string_list(), not a Label attribute. Passing Starlark Label objects directly causes an immediate Bazel analysis type error.
  • Citation: rules_cc cc_shared_library.bzl (“exports_filter is a list of strings attribute”).

macOS Dynamic Lookup Link Flag

• Apple's ld64/lld linkers require -undefined dynamic_lookup in user_link_flags on macOS so CPython C-API symbols remain unresolved at link time and resolve dynamically at runtime.

Linux Platform Tag Composition

• Linux platform tags are formatted as {platform_machine}-linux-{libc} (e.g., x86_64-linux-gnu or aarch64-linux-musl).
• Citation: PEP 600 — Perennial manylinux & PEP 656 — musllinux.