Malte UblandClaude Opus 5.5 3b9272e8f8 Keep Date slots out of runtime-optional undefined widening ...

The runtime-optional analysis widens a parameter or binding that can
observe undefined with an undefined arm. For a Date it interned the
union `Date | undefined`, which is not a valid union (Date is not a
union arm kind), and the whole program failed IR validation with SC9001
"union uN: arm 0 is date" (morgan's date token and clfdate).

Like generators, a Date keeps its type: the canonical undefined-arm
helper already refuses Date, and a site that would store undefined into
the slot keeps its own diagnostic.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

2026-10-18 13:51:44 -07:00

..

corpus

Keep Date slots out of runtime-optional undefined widening

2026-10-18 13:51:44 -07:00

coverage-fixtures

Report record width copies at assertions, assignments and array elements

2026-10-16 14:02:02 -07:00

deadstrip

…

diagnostics

Merge main

2026-10-18 12:28:02 -05:00

ffi

Support three.js meshes and materials in static builds

2026-09-29 23:34:18 -05:00

fixtures

Merge main

2026-10-18 12:01:19 -05:00

harness

Convert a Date to local time once for its local getters and follow TZ changes (#1313)

2026-10-18 13:57:42 -05:00

library-mode

Add the cstring class to library profiles

2026-10-17 23:40:06 -05:00

test262

Make scriptc compilation native-only

2026-10-12 12:25:30 -05:00