I probably deserve this:

$ gsi main.scm
Segmentation fault

this isn't an error in my scheme code, there's probably something broken with some weird C interface. Question is ... how do I load up gdb? (I just want a stack trace). Even if there are lots of weird gambit related functions that I have no idea about, it's okay; the only other cohice I have to sprinkle my code with lots of print statements, and I think this is a better way. :-)

Thanks!