Your bug report

#66507: 30.0.50; Cannot build some modules without adding LOCAL_EXPORT_CFLAGS=-isystem ... on Android port.

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 66507@debbugs.gnu.org.

-- 
66507: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=66507
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