On Tue, Dec 11, 2012 at 4:42 AM, Ludovic Courtès <[email protected]> wrote: > > The VM does full error checking. But there’s a difference between > checking whether an object has the expected type, and checking whether > an object is a well-formed ‘SCM’ object (and NULL is not a valid ‘SCM’ > object.) > > Guile never does the latter, and as a rule of thumb I would keep things > this way. >
Okay. > The brave hacker working on a compiler can easily figure out what how to > debug all sorts of crazy things. :-) > Yes, "easily". :-) > So I’m closing it for now. > > Thanks, > Ludo’. > > PS: It’s still unclear to me how you ended up forging an invalid SCM > object. I think you either have to generate invalid bytecode, or to > use (pointer->scm %null-pointer), or variants thereof. > I loaded a procedure on the stack, used the new-frame instruction, and then the call instruction. When I switched the order of the first two things, the problem went away. I must have been using uninitialized stack space. Noah
