Bug 306542 – Compilation error with -Wunsafe-buffer-usage-in-format-attr-call when using latest Swift toolchain

• Component: New Bugs
• Status: RESOLVED FIXED

[Ryosuke Niwa]

Using main Swift toolchain, we hit the following error:
```
/Volumes/Data/webkit/Source/WTF/wtf/cocoa/SystemTracingCocoa.cpp:56:36: error: formatting function '__builtin_os_log_format_buffer_size' is unsafe [-Werror,-Wunsafe-buffer-usage-in-format-attr-call]
   56 |         FOR_EACH_WTF_SIGNPOST_NAME(WTF_SIGNPOST_EVENT_BEGIN_INTERVAL_CASE_LABEL)
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /Volumes/Data/webkit/Source/WTF/wtf/cocoa/SystemTracingCocoa.cpp:27:
/Volumes/Data/webkit/Source/WTF/wtf/SystemTracing.h:275:5: note: expanded from macro 'FOR_EACH_WTF_SIGNPOST_NAME'
  275 |     M(AccessibilityIsolatedTreeApplyPendingChanges) \
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Volumes/Data/webkit/Source/WTF/wtf/cocoa/SystemTracingCocoa.cpp:53:45: note: expanded from macro 'WTF_SIGNPOST_EVENT_BEGIN_INTERVAL_CASE_LABEL'
   53 |     WTF_SIGNPOST_EVENT_EMIT_FUNC_CASE_LABEL(os_signpost_interval_begin, name, " %{signpost.description:begin_time}llu")
      |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Volumes/Data/webkit/Source/WTF/wtf/cocoa/SystemTracingCocoa.cpp:47:9: note: expanded from macro 'WTF_SIGNPOST_EVENT_EMIT_FUNC_CASE_LABEL'
   47 |         emitFunc(log, signpostIdentifier, #name, "pid: %d | %{public}s" timeFormat, pid, logString, timestamp); \
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /Volumes/Data/webkit/Source/WTF/wtf/cocoa/SystemTracingCocoa.cpp:27:
In file included from /Volumes/Data/webkit/Source/WTF/wtf/SystemTracing.h:260:
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator26.2.sdk/usr/include/os/signpost.h:227:9: note: expanded from macro 'os_signpost_interval_begin'
  227 |         os_signpost_emit_with_type(log, OS_SIGNPOST_INTERVAL_BEGIN, \
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  228 |                 interval_id, name, ##__VA_ARGS__)
      |                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator26.2.sdk/usr/include/os/signpost.h:398:9: note: expanded from macro 'os_signpost_emit_with_type'
  398 |         _os_signpost_emit_with_type(_os_signpost_emit_with_name_impl, log, \
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  399 |                 type, spid, name, ##__VA_ARGS__)
      |                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator26.2.sdk/usr/include/os/signpost.h:390:13: note: expanded from macro '_os_signpost_emit_with_type'
  390 |             OS_LOG_CALL_WITH_FORMAT_NAME((emitfn), \
      |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  391 |                     (&__dso_handle, _log_tmp, _type_tmp, _spid_tmp), \
      |                     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  392 |                     name, "" __VA_ARGS__); \
      |                     ~~~~~~~~~~~~~~~~~~~~~
```

[Ryosuke Niwa]

Pull request: https://github.com/WebKit/WebKit/pull/57489

[EWS]

Committed 306552@main (ca919f13d3de): <https://commits.webkit.org/306552@main>

Reviewed commits have been landed. Closing PR #57489 and removing active labels.

[Radar WebKit Bug Importer]

<rdar://problem/169333660>