cstruct: ship a Wasm runtime (cstruct.wat), the analog of cstruct.js#320
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cstruct: ship a Wasm runtime (cstruct.wat), the analog of cstruct.js#320samoht wants to merge 2 commits into
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/cc @vouillon - is this the right way to support wasm_of_ocaml ? |
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Looks good. The functions already exist under another name. So you can also just reexport them. |
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The wasm_of_ocaml (wasm_files ...) stanza needs dune language 3.17, so bump dune-project and the dune lower bound in every package -- otherwise opam may resolve an older dune (e.g. 2.3) that cannot parse the project. Lang 3.17 also makes the dev profile treat warning 32 (unused value) as an error, so drop the unused pp_cstruct in the fuzzer and use the compile-test binding in the lwt ppx test.
wasm_of_ocaml already provides the bigstring blit, memset and memcmp operations, so cstruct.wat re-exports them under cstruct's stub names; only caml_check_alignment_bigstring is cstruct-specific.
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wasm_of_ocaml resolves a library's C primitives from Wasm modules registered with (wasm_of_ocaml (wasm_files ...)), importing runtime helpers from the env namespace. cstruct.wat mirrors cstruct.js one to one: the three bigstring blits alias the runtime's caml_bigstring_blit_* exports, fill and compare loop over caml_ba_set_1 / caml_ba_get_1 + caml_int_compare, and check_alignment is always true. Without it a program that links cstruct cannot run as wasm (the blit primitives get dummy stubs that throw).