`gprinstall` raises `Constraint_Error`

[jquorning]

gprinstall from Alire and Debian 13 raises Constraint_Error when installing the Alire AWS crate.

The error report:
alire-project/alire#2084

[saper]

The crash happens here

gprbuild/src/gprinstall-install.adb

Line 1230 in 3db10ae

Excluded_Naming.Include (Get_Name_String (Sid.Unit.Name));

because Sid.Unit is zero.

I have noticed that Process_Exceptions_Unit_Based

gprbuild/gpr/src/gpr-nmsc.adb

Lines 4909 to 4921 in b07f6ff

	Add_Source
	(Id => Source,
	Data => Data,
	Project => Project,
	Source_Dir_Rank => 0,
	Lang_Id => Lang_Id,
	Kind => Kind,
	File_Name => File_Name,
	Display_File => File_Name_Type (Element.Value.Value),
	Unit => Unit,
	Index => Index,
	Location => Element.Value.Location,
	Naming_Exception => Naming_Exception);

adds the source files with the Unit set

while Process_Exceptions_File_Based knows no Unit:

gprbuild/gpr/src/gpr-nmsc.adb

Lines 4793 to 4803 in b07f6ff

	Add_Source
	(Id => Source,
	Data => Data,
	Project => Project,
	Source_Dir_Rank => 0,
	Lang_Id => Lang_Id,
	Kind => Kind,
	File_Name => File_Name,
	Display_File => File_Name_Type (Element.Value),
	Naming_Exception => Yes,
	Location => Element.Location);

Shouldn't those sources be different types? The Naming_Exception flag seems to have double meaning....

There is something wrong with that logic, because a simple check for Sid.Unit causes gprinstall to ignore affected files.