Hojun-Cho
4e1181fd8c
wwstage exprtype's N_CALL arm fell into a global-leaf scopelookup for an N_DOT callee with a value or chained receiver, binding whatever same-named global headed the scope bucket. Under a late-os combined.ww concat order this resolved io's `s.read(...)` to os.read (i64) instead of the field's fn type, so checkretassign confidently rejected a valid tagged return — an import-order-sensitive false positive. cstage resolves a call result solely from the callee expr's own type (check.c:1378-1433, mirroring harec check_autodereference 1566-1581); drop the global-leaf else-arm so value and chained receivers fall through to the existing fn-VALUE path at check.ww:2455. SK_USE module-qualified calls are unchanged. ww has no methods, so `value.leaf()` is only ever a fn-ptr field access; the global hit was never legitimate. Zero .s delta across all 5 bootstrap tools (the branch is dead in the bootstrap); test 776 graduates to both stages (os-late order, byte-identical). The fix unmasks a pre-existing wwstage cgen bug (#211): cgen also re-derives a call's return shape by name (fnretlookup), so a value-receiver field call whose leaf collides with a same-named global of a different register shape mis-resolves cs!=ww. Documented at the cgen site; pinned cstage-only by test/wcc/782 (graduates to STAGE_WW on #211 close).
61 KiB
61 KiB