RESOLVED FIXED326814
Add disable-round-trip-debug-types 
https://bugs.webkit.org/show_bug.cgi?id=326814
Summary Add disable-round-trip-debug-types
adrian_taylor
Reported 2026-10-08 07:10:57 PDT
Adds -Xfrontend -disable-round-trip-debug-types to work around two crashes in the Swift compiler's debug-info generation (IRGen). It aborts on a captured mutable variable of a namespaced C++ reference type such as IPC.Connection (rdar://189511928). It also aborts on SwiftUI Material, which has two declarations under the same ABI module name because of WebKit's SwiftUI_SPI stub (rdar://189512247). The flag can be removed once both are fixed. Reproduction instructions with WebKit: (note that this is one of five different workarounds required to have the following commands fully succeed, so you may not hit this bug first) Install swift-DEVELOPMENT-SNAPSHOT-2026-10-06 from swift.org. Check out WebKit main OpenSource version 59f9ffb4cd6d831db26878a6e097d25967fd532d, without an Internal directory alongside. ln -s $(xcrun -f metal) /Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2026-10-06-a.xctoolchain/usr/bin/metal. (DEVELOPER_DIR=/Applications/XcodePublic.app make debug EXPORT_COMPILE_COMMANDS=YES 2>&1 TOOLCHAINS=$(plutil -extract CFBundleIdentifier raw /Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2026-10-06-a.xctoolchain/Info.plist)) 2>&1 | tee log.txt
Attachments
Add attachment proposed patch, testcase, etc.
Radar WebKit Bug Importer
Comment 1 2026-10-08 07:11:07 PDT
<rdar://problem/189516426>
adrian_taylor
Comment 2 2026-10-08 07:12:12 PDT
Pull request: https://github.com/WebKit/WebKit/pull/76318
EWS
Comment 3 2026-10-08 10:22:16 PDT
Committed 323131@main (3376a82ffffa): <https://commits.webkit.org/323131@main> Reviewed commits have been landed. Closing PR #76318 and removing active labels.
Note You need to log in before you can comment on or make changes to this bug.