An overlong array literal (more initializers than the declared length) is
invalid -- cstage loud-rejects it everywhere -- but wwstage silently
accepted (and truncated) it in several positions; #9 wired only the decl
position. This folds the remaining three (one class: checkarrlitfits
over-fill coverage), all wwstage-only reject-align:
- #12a return fn f() [2]int = [1,2,3] -- silently accepted.
- #12b call-arg g([1,2,3]) -- louded only late via cgen #271.
- #106 alias type A=[2]int; let g: A = [1,2,3] -- silently truncated;
checkarrlitfits bailed on the N_TNAME alias without chasing.
Four inserts in check.ww: an alias-chase (resolvealias) at the top of
checkarrlitfits (makes all callers alias-aware), the over-fill check wired
into checkretassign (hoisted above the isassignable short-circuit) and
desugarcallargs, and the alias-let-global guard made alias-aware. cstage
unchanged (w6c md5 unchanged); reject-only, so no asm moves -- 990-997 8/8,
no lib byte-id pin flips. A 5th position (tuple-element overlong) is a
separate pre-existing hole, filed (#20). test/wcc/828 table-driven.