fix: improper use of ucal_inDaylightTime#6097
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daksh-goyal wants to merge 4 commits intomicrosoft:mainfrom
Open
fix: improper use of ucal_inDaylightTime#6097daksh-goyal wants to merge 4 commits intomicrosoft:mainfrom
daksh-goyal wants to merge 4 commits intomicrosoft:mainfrom
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`ucal_inDaylightTime` is used to check whether the timezone is currently observing DST. STL (likely in an attempt to be defensive) tries to use it as a way to tell whether the timezone observed DST on the date in question (which could be in the past), which is wrong.
StephanTLavavej
requested changes
Feb 22, 2026
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StephanTLavavej
requested changes
Feb 22, 2026
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@microsoft-github-policy-service agree company="Microsoft" |
Added regression tests for timezones that abolished DST to ensure correct historical offsets.
StephanTLavavej
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Feb 22, 2026
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Thanks! I've manually verified that the regression test produced all wrong answers before the fix. |
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ucal_inDaylightTimeis used to check whether the timezone is currently observing DST. STL (likely in an attempt to be defensive) tries to use it as a way to tell whether the timezone observed DST on the date in question (which could be in the past), which is wrong.Fixing that by omitting use of that guard before obtaining DST offset.
fixes: #6096