Build fails on ppc64le due to MUST_TAIL_CALL when tail call is not possible

[mcatanzaro]

1f02186

Build fails on ppc64le due to MUST_TAIL_CALL when tail call is not possible
https://bugs.webkit.org/show_bug.cgi?id=279985

Reviewed by Adrian Perez de Castro.

Our use of clang::musttail attribute is not supported by Clang on
ppc64le and needs to be removed. See
llvm/llvm-project#93267 and
llvm/llvm-project#98859 and
llvm/llvm-project#108014 for more info.

This change is authored by Dan Horák (thank you!).

* Source/WTF/wtf/Compiler.h:

Canonical link: https://commits.webkit.org/285261@main

6b424d0

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 win
	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	✅ 🧪 win-tests
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 wpe-cairo
✅ 🛠 🧪 jsc	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
✅ 🛠 🧪 jsc-arm64	✅ 🛠 vision	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 vision-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
✅ 🛠 🧪 merge	✅ 🧪 vision-wk2	✅ 🧪 mac-intel-wk2	✅ 🛠 jsc-armv7
	✅ 🛠 tv		❌ 🧪 jsc-armv7-tests
	✅ 🛠 tv-sim
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 7c79dd4)

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 win
	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	✅ 🧪 win-tests
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 wpe-cairo
✅ 🛠 🧪 jsc	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
✅ 🛠 🧪 jsc-arm64	✅ 🛠 vision	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 vision-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
	✅ 🧪 vision-wk2	✅ 🧪 mac-intel-wk2	✅ 🛠 jsc-armv7
	✅ 🛠 tv	⏳ 🛠 mac-safer-cpp	❌ 🧪 jsc-armv7-tests
	✅ 🛠 tv-sim
	✅ 🛠 watch
	✅ 🛠 watch-sim

[mcatanzaro]

For avoidance of doubt: the changes to Skia are contributed only under Skia's standard BSD-style license.

[aperezdc]

I would rather submit this to Skia, like we have been doing so far with all the patches we have needed until now, instead of permanently carrying a patch that needs to be applied on our end every time we want to update Skia.

[mcatanzaro]

Unfortunately I'm not authorized to contribute to Skia.

[aperezdc]

Unfortunately I'm not authorized to contribute to Skia.

@mcatanzaro Would it be okay with you if I submit the patch to upstream Skia myself, mentioning you are the author in the commit log?

[mcatanzaro]

Yes, except it's mostly authored by Dan, not be me. We'd love to see this included in Skia.

(However, it seems likely that if you state you're not the author, the change will be rejected. Good luck....)

[aperezdc]

Submitted to Skia, let's see how that goes: https://skia-review.googlesource.com/c/skia/+/910216

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 0d29de4)

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	🛠 ios	🛠 mac	🛠 wpe	🛠 win
	🛠 ios-sim	✅ 🛠 mac-AS-debug	🧪 wpe-wk2	🧪 win-tests
🧪 webkitperl	🧪 ios-wk2	🧪 api-mac	🧪 api-wpe
	🧪 ios-wk2-wpt	🧪 mac-wk1	🛠 wpe-cairo
🛠 🧪 jsc	🧪 api-ios	🧪 mac-wk2	🛠 gtk
🛠 🧪 jsc-arm64	🛠 vision	⏳ 🧪 mac-AS-debug-wk2	🧪 gtk-wk2
	🛠 vision-sim	🧪 mac-wk2-stress	🧪 api-gtk
	⏳ 🧪 vision-wk2	🧪 mac-intel-wk2	🛠 jsc-armv7
	🛠 tv		🧪 jsc-armv7-tests
	🛠 tv-sim
	🛠 watch
	🛠 watch-sim

[webkit-early-warning-system]

EWS run on current version of this PR (hash 6b424d0)

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 win
	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	✅ 🧪 win-tests
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 wpe-cairo
✅ 🛠 🧪 jsc	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
✅ 🛠 🧪 jsc-arm64	✅ 🛠 vision	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 vision-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
✅ 🛠 🧪 merge	✅ 🧪 vision-wk2	✅ 🧪 mac-intel-wk2	✅ 🛠 jsc-armv7
	✅ 🛠 tv		❌ 🧪 jsc-armv7-tests
	✅ 🛠 tv-sim
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-commit-queue]

Committed 285261@main (1f02186): https://commits.webkit.org/285261@main

Reviewed commits have been landed. Closing PR #33906 and removing active labels.