ModemManager-compat.h has #include <glib.h>, so the glib include dirs need to be passed to the compiler. Otherwise compilation of projects depending on MM headers (such as modemmanager-qt) fails.
Hey Antonio! Thanks for the report; I just got this fixed in ModemManager git master like today :) Got the same issue building ModemManagerQt myself. The fix I applied, though, is to avoid using glib all together in the MM core headers.
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