Fix prune of callback modules from AVM libs#60
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src/packbeam_api.erl
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| StrippedData = strip_padding(Data), | ||
| {ok, {Module, ChunkRefs}} = beam_lib:chunks(StrippedData, [imports, exports, atoms]), | ||
| [{module, Module}, {chunk_refs, ChunkRefs}, {data, StrippedData} | Accum]; | ||
| {ok, _, AllChunks} = beam_lib:all_chunks(StrippedData), |
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We do chunks and then all_chunks?
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When using prune with modules sourced from a .avm library, modules referenced only in literals (e.g., supervisor callback modules in child specs) were incorrectly pruned. The root cause was that parse_beam (the AVM parsing path) did not extract the literals chunk, so get_atoms/1 could not find atoms that only appear in the literals table — such as a worker module name inside a supervisor child spec map. The fix extends the existing beam_lib:chunks/2 call in parse_beam to also fetch the raw "LitT" and "LitU" chunks (compressed and uncompressed literals, respectively), and extracts uncompressed_literals inline. This keeps it to a single beam_lib call and handles both OTP < 28 (compressed LitT) and OTP >= 28 (uncompressed LitT, or LitU from repackaged AVMs). Signed-off-by: Peter M <petermm@gmail.com>
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| %% Copyright (c) 2026 AtomVM | |||
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Fixes: #58
https://ampcode.com/threads/T-019c6de0-ba10-7688-bedb-4ce12d207c0a
When using -p (prune) with modules sourced from a .avm library, modules referenced only in literals (e.g., supervisor callback modules in child specs) were incorrectly pruned.
The root cause was that parse_beam (the AVM parsing path) did not extract uncompressed_literals, while the .beam parsing path (parse_file(beam, ...)) did. This meant get_atoms/1 could not find atoms that only appear in the literals table — such as a worker module name inside a supervisor child spec map — when the containing module came from an .avm file.
The fix adds literal extraction to the AVM parsing path, making it consistent with the .beam path.
Test modules added (test/prune_sup/):
start_mod.erl — entrypoint that calls my_sup
my_sup.erl — supervisor-like module with my_worker only in a literal child spec (not in atoms chunk or imports) my_worker.erl — callback module, never directly imported
Tests added:
packbeam_create_prune_supervisor_callback_test — verifies pruning keeps literal-only references (all .beam inputs) packbeam_create_prune_supervisor_callback_from_avm_test — same scenario with modules from a .avm lib (was failing before the fix)