fix: ensure lean_initialize is called when Lean is only privately imported - #14505
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Benchmark results for 16f8546 against 3259610 are in. (These commits have already been benchmarked in a previous command.) No significant results found. @Kha
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Benchmark results for 16f8546 against 3259610 are in. (These commits have already been benchmarked in a previous command.) No significant results found. @Kha
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Benchmark results for leanprover-community/mathlib4-nightly-testing@8b920c2 against leanprover-community/mathlib4-nightly-testing@eaeb601 are in. No significant results found. @Kha
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The adaptation PR for this PR is leanprover/downstream-lean4#9. |
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… imported When a `module` privately imports (parts of) `Lean` and that module is used by an executable whose root module does not visibly import `Lean`, the emitted `main` called only `lean_initialize_runtime_module`, so the C++ components of the Lean package (kernel, library, ...) were never initialized and the executable crashed at startup. Localize the initialization decision into each module: the generated initializer of every module whose environment shows runtime use of the `Lean` package now calls `lean_initialize` itself (except for modules of the core packages, which `lean_initialize` initializes), and the emitted `main` always calls just `lean_initialize_runtime_module`. Make `lean_initialize` and `lean_initialize_runtime_module` idempotent so repeated calls from several module initializers are no-ops. The LLVM emitter keeps the previous `main`-level check as it has no module system support. Also add a regression test building and running such an executable. Co-Authored-By: Claude feat: initialize the Lean runtime in every generated module initializer Every generated module initializer now calls `lean_initialize_runtime_module` (or, for modules using the `Lean` package, the full `lean_initialize`) before anything else, so external users of a Lean library no longer have to remember calling it before the library's initializer. Both functions are idempotent, so the emitted `main` and existing embedders that already call them are unaffected. Co-Authored-By: Claude doc: drop manual runtime initialization from the reverse FFI example Module initializers now initialize the Lean runtime themselves, so the example no longer needs to call `lean_initialize_runtime_module` first; a comment notes the call is still required on older toolchains. This also makes the example test verify the new self-initialization behavior. Co-Authored-By: Claude
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…d `main` The module initializer that `main` calls initializes the runtime itself, so `main` no longer needs to call `lean_initialize_runtime_module` beforehand. Co-Authored-By: Claude
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… imported (#14505) This PR fixes a compiler issue where private imports of the `Lean` library could lead to segfaults by ensuring the necessary call to `lean_initialize` happens in each module's initializer when necessary. As a follow-up clean up, the call to `lean_initialize_runtime_module` is made implicit as well, meaning users of Lean as an FFI library do not need to call these functions themselves anymore.
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This PR fixes a compiler issue where private imports of the
Leanlibrary could lead to segfaults by ensuring the necessary call tolean_initializehappens in each module's initializer when necessary. As a follow-up clean up, the call tolean_initialize_runtime_moduleis made implicit as well, meaning users of Lean as an FFI library do not need to call these functions themselves anymore.