[Issue 21940] Compiler flags -check=on/off not recognized

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=21940

--- Comment #3 from Dlang Bot <dlang-bot at dlang.rocks> ---
dlang/dmd pull request #12600 "merge stable" was merged into master:

- fea011ecb74ca6f9a9124980e3ec0c9c60a5f7e3 by MoonlightSentinel:
  Fix 21940 - Recognize on/off as valid options for -check

  Check for the special values `"on"` and `"off"` before parsing
  `<option>=<state>`.

https://github.com/dlang/dmd/pull/12600

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