Do not leave COBJ-ified mp_int uninitialized.

Here we ensure that the digits pointer of an uninitialized
mp_int is nulled out.  The garbage collector could conceivably
encounter such an object, in which case mp_clear will then try
to free a garbage pointer. This could happen if an exception
is thrown out of numeric code due to low memory, interrupting
its execution, leaving behind an unfilled object produced
by make_ubignum.

* arith.c (make_ubignum): Perform minimal
initialization of the mp_int using new function.

* mpi/mpi.h (mp_init_minimal): New inline function.

1 files changed, 1 insertions, 0 deletions

diff --git a/arith.c b/arith.c
index 1c3c33ce..5eb022ec 100644
--- a/arith.c
+++ b/arith.c
@@ -62,6 +62,7 @@ static val make_ubignum(void)
 {
   val n = make_obj();
   n->bn.type = BGNUM;
+  mp_init_minimal(&n->bn.mp);
   return n;
 }