The problem seems to be that Yap defines its own allocation functions for gmp objects:
#ifdef USE_GMP /* YAP style memory allocation */ mp_set_memory_functions( AllocBigNumSpace, ReAllocBigNumSpace, FreeBigNumSpace); #endif
This allows Yap to work with such objects in its own stacks. Unfortunately, these functions require for another function, PreAllocBigNum to have been called before. In general, using them is a bit dangerous, because they assume they have control over the global stack.
I suppose Yap is polluting the application space, so the correct solution would be for Yap to reset these functions before entering user code. But this would make the interface slower for any application that doesn't use GMP.
A compromise might be for me to provide two interface functions (YapResetGMPFunctions() and YapSet GMPFunctions()) and for you to call them before you started manipulating GMP objects.
Cheers,
Vitor