Commit 270669@main for bug 264488 added usage of arch-specific intrinsics, by backporting a Chromium patch, but it did not include the matching headers. This caused a build failure on my ARM platform.
Pull request: https://github.com/WebKit/WebKit/pull/20926
Committed 271372@main (920ba07bf75f): <https://commits.webkit.org/271372@main> Reviewed commits have been landed. Closing PR #20926 and removing active labels.
<rdar://problem/119026237>