Those interested in XL may also find the much older GalaxC by John Beetem interesting: https://community.element14.com/technologies/fpga-group/b/bl...
EDIT: Joking aside, I would love to hear a compare & contrast between Galaxy/GalaxC & LX/XL, though!!
EDIT2: and via that first link, I think you can get to a full source code distribution compile-able with C on 32-bit Linux. Might have its own woes like LLVM hosting, but those might also be more solvable as part of a 64-bit port.