Hojun-Cho
6f10c832a4
Cstage's check.c:981-1006/1052-1082 builds a real (*T|nomem) / ([]T|nomem) return type for the alloc builtin; wwstage was returning nil from exprtype's N_CALL arm (alloc is SK_FN with decl=nil under seedprimitives), and checkletassign early-returned on nil src, silently accepting `let p: *T = alloc(v);` without `!`. Stage asymmetry that #30 papered over until now. Three coordinated edits in check.ww: - exprtype N_CALL: synthesize N_TTAGGED{N_TPTR{argt}, nomem} or {N_TSLICE{u8}, nomem} for bare alloc (same-module gated, mirrors cstage check.c:981-985 / task #23). - exprtype N_TRYUNW: project the success variant so `let p:*T = alloc(v)!;` resolves rhs to *T. - isassignable: tagged → non-tagged is unconditionally not assignable, forcing match/?/!. 950_selfcheck.c rows pin both ptr and slice forms.