Yes and no. The film plane to lens mount distance for FD is about the shortest for any SLR. Thus, it can't really be easily adapted to any other camera. There are basically five options:
1. Get the uber-expensive genuine Canon adapter. (las on on ebay was $1000+) There's virtually no loss in optical quality, but it only works on lenses longer than 200mm and it acts like a TC, so you lose 2/3 of a stop.
2. Get a cheap adapter ring from like B&H There's no loss in optical quality, but you can't focus to infinity.
3. Get a cheap knockoff of the Canon adapter. It'll cost about $60, but there are the same problems as with the Canon adapter, plus the optical quality sucks.
4. Adapt the lenses permanently to EOS. It's possible, there was a guy who did a few lenses (including wide angles), but got sick and stopped doing conversions. There's no loss in optical quality, but metering is stopped down only. The lenses can never go back to FD mount. Nevertheless, this shows that it is at least possible.
5. Just use you FD lenses on your A-1, and likewise for the EF lenses!
I hope this helps.