[gnufx]

Not relevant to GCC, but one use for an old A68 compiler was apparently to be adapted for the old NA Software Fortran 90 compiler, I was told by a former colleague. I'd have expected Ada to be a closer fit, and I don't know how well the decision worked out.

[firesteelrain]

GCC Gnat frontend is used for modern Ada development these days. Not sure if that’s what you mean