Bug 270769 – [JSC] DatePrototype.cpp(337,29): error: 'snprintf' will always be truncated; specified size is 28, but format string expands to at least 29 [-Werror,-Wformat-truncation]

• Status: RESOLVED
• Resolution: FIXED
• Component: JavaScriptCore

[Fujii Hironori]

Clang 18.0.1 reports an warning for Windows port.

In file included from C:\w\WebKitBuild\Debug\JavaScriptCore\DerivedSources\unified-sources\UnifiedSource-f2e18ffc-8.cpp:1:
C:\PSDEV\wc\Source\JavaScriptCore\runtime/DatePrototype.cpp(337,29): error: 'snprintf' will always be truncated; specified size is 28, but format string expands to at least 29 [-Werror,-Wformat-truncation]
  337 |         charactersWritten = snprintf(buffer, sizeof(buffer), "%+07d-%02d-%02dT%02d:%02d:%02d.%03dZ", gregorianDateTime->year(), gregorianDateTime->month() + 1, gregorianDateTime->monthDay(), gregorianDateTime->hour(), gregorianDateTime->minute(), gregorianDateTime->second(), ms);
      |                             ^
1 error generated.

[Fujii Hironori]

Seems like this issue.

-Wformat-truncation warning size does not agree with the return value from snprintf · Issue #71320 · llvm/llvm-project
https://github.com/llvm/llvm-project/issues/71320

[Fujii Hironori]

Pull request: https://github.com/WebKit/WebKit/pull/25692

[EWS]

Committed 275926@main (65fd9be34cc1): <https://commits.webkit.org/275926@main>

Reviewed commits have been landed. Closing PR #25692 and removing active labels.

[Radar WebKit Bug Importer]

<rdar://problem/124404812>