Hojun-Cho
cf9d83b209
Two composing defects made a two-enum union mis-tag in wwstage (live cs!=ww: `let e: (color|shape) = shape.BALL` stored tag 0 — the color arm — while cstage stored 1). type_eq/typeeq had no TY_ENUM arm, so ANY two enums fell into the primitive default and compared equal; enums are nominal (harec: an enum IS its alias type) and now compare by node identity only. Underneath, the wwstage post-order revisit re-stamped the constant-folded enum member (an N_INTLIT) as untyped_int, clobbering the enum stamp the N_DOT fold applied, so the widen matcher fell to its first-variant fallback -- the #59.9 N_BIN guard now twins on N_INTLIT (cstage cexpr is single-pass and never clobbered).