__thiscall calling convention (used, for example, in
Buzz machine interface) is not implemented.
This calling convention is used automatically by VC++
for method calls when __fastcall is used as standard
calling convention. The difference between __thiscall
and __fastcall is that __fastcall passes two arguments
in registers (ECX and EDX, IIRC) while __thiscall
passes only 'this' pointer in ECX, and the rest is
pushed on the stack. The lack of __thiscall can be
worked around by using __thiscall and adding a dummy
'int' argument in front of other arguments (which would
reserve EDX so that the next arguments are pushed on
stack) - but it would be nicer to have this built in.