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## Summary - honor `--dynamic_mode=fully` when calling `cc_common.link` - add Starlark analysis tests for runtime selection and shared `link_deps` - compare Rust linkage behavior with equivalent `cc_binary` targets ## Why `cc_common.link` defaults `link_deps_statically` to true. Rust targets therefore selected the static C++ runtime even under fully dynamic linking. ## Impact Rust targets using `cc_common.link` now select the dynamic C++ runtime when built with `--dynamic_mode=fully`, matching `cc_binary` behavior. ## Validation ``` $bazel test //... ... Executed 578 out of 608 tests: 578 tests pass and 30 were skipped. ``` This is a follow-up to 226c488
krasimirgg
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Sep 29, 2026
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Hey, thank you, this is very nice!
I think there may be a couple of other stray places where we need to plumb these cc-std-dylibs for this setup to work. Could you add a toy example like a rust_binary that depends on a cc_library that exercises the C++ stdlib, and a test that runs the rust_binary under --dynamic_mode=fully (e.g., via a user-defined transition), ensuring that it succeeds at runtime (so the necessary cc-std-dylibs are appropriately made available to the rust binary at dynamic-link-time? -- and if that setup doesn't match your intended real use case please let me know :)
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Summary
--dynamic_mode=fullywhen callingcc_common.linklink_depscc_binarytargetsWhy
cc_common.linkdefaultslink_deps_staticallyto true. Rust targets therefore selected the static C++ runtime even under fully dynamic linking.Impact
Rust targets using
cc_common.linknow select the dynamic C++ runtime when built with--dynamic_mode=fully, matchingcc_binarybehavior.Validation
This is a follow-up to 226c488