I have had a try at using Gnat Studio with the Alire package manager. Launching Gnat Studio using the 'alr edit' command is causing Gnat Studio to crash. I have had a look at the log file and there are several .dll files causing exceptions. The file entries are like this:

[PROJECTS.EXCEPTIONS] Unexpected exception: raised CONSTRAINT_ERROR : gnatcoll-projects.adb:5729 index check failed _PROJECTS.EXCEPTIONS_ [C:\GNATSTUDIO\bin\gps.libgnatcoll\libgnatcoll.dll] _PROJECTS.EXCEPTIONS_ 0x7ffc78dcecb8 ??? at ???

Gnat Studio opens in an 'inconsistent state' and crashes.

Regards Mike