Bend · Issues· 24 open

Type checking a large Nat literal overflows the host stack without identifying the literal

The Guide feels like AI slop and I don't understand it

The @unsafe count is disclosed only on the no-main path: a harmless main, or any -o emit/build, reports nothing

Array structural split/join allocates and copies (blk_half/blk_node); the paper says both halves come in place and joining is free

JS lane: Char.to_upper throws on control characters ('\n', '\t') because the mapped Chr is built outside the selected Bool.pick branch

JS lane: List.length over a long list dies with a stack overflow (the base recursion is not in tail position); a tail counter over the same list completes

C lane F32.read accepts what the JS lane rejects: hex floats, nan(...), and a prefix accepted before an embedded NUL

JS backend: String.split/String.length recurse per character and overflow the JS stack on ~10k+ char strings (found by DeepSeek V4.1 Flash)

All foreign .js sources share one scope, so a private helper in one FFI module silently clobbers another's (C lane refuses)

Foreign effect names collide: eff_name folds case and separators, so two defs silently share one FFI slot (C lane refuses)

JS backend violates a machine-checked theorem: F32 does not preserve signaling-NaN bits (found by opus 4.8)

Hub: partial package installs never self-heal for foreign .c/.js files (raw ENOENT from eff_src)

bend.ts accepts books the Lean kernel refuses: base-file live calls to later-filled laws, and non-Tree bodies

IO receive effects eagerly allocate the caller-supplied max and abort the whole process (_exit) on allocation failure

Checker recursion depth: valid programs with ~10k-deep terms (e.g. a 10000n literal) fail with "machine stack overflowed"