Ross

...

* Nonterm generates:

...

* Segfault generates:

Under Linux, I get "Garbage collection fails to reclaim sufficient space" for both of these.

By tweaking the code a bit I was able to get GC messages, but the examples above crash. I suspect the crash is rather fragile - minor alternations like removing expressions that seemingly have no interaction fix this crash. I suspect it will be hard to replicate unless you use the actual binary from WinHugs. I have replicated this on my other Windows machine, with the same binaries, and the same result. Perhaps running this example under Valgrind will show up something? Thanks Neil

Hi

I wonder if this is related to the reason that optimization is turned off for certain files (search for "Modules to be compiled without optimization" in src/Makefile.in). During the static analysis and type checking phases, the mark phase of the Hugs garbage collector also looks for cells on the C stack (this is omitted during evaluation, because all the primitives are carefully written to ensure that everything is reachable from the Hugs stack). Optimization may obscure these cell references, which would certainly cause crashes.

Oh, I had no idea that optimisation was turned off for certain files - with the Windows build its turned on for all files. I guess if something is that sensitive to optimisation, the Windows compiler could be doing anything to it... Thanks Neil