crypto/bn/bn_lib.c:453: error: NULL_DEREFERENCE
  pointer `b` last assigned on line 449 could be null and is dereferenced at line 453, column 8.
Showing all 6 steps of the trace


crypto/bn/bn_lib.c:432:1: start of procedure bn_expand2()
430.    * NULL is returned. If not, 'b' is returned. */
431.   
432. > BIGNUM *bn_expand2(BIGNUM *b, int words)
433.   	{
434.   	BN_ULONG *A;

crypto/bn/bn_lib.c:437:6: Taking true branch
435.   	int i;
436.   
437.   	if (words > b->dmax)
            ^
438.   		{
439.   		BN_ULONG *a = bn_expand_internal(b, words);

crypto/bn/bn_lib.c:439:3: Skipping bn_expand_internal(): empty list of specs
437.   	if (words > b->dmax)
438.   		{
439.   		BN_ULONG *a = bn_expand_internal(b, words);
         ^
440.   
441.   		if (a)

crypto/bn/bn_lib.c:441:7: Taking false branch
439.   		BN_ULONG *a = bn_expand_internal(b, words);
440.   
441.   		if (a)
             ^
442.   			{
443.   			if (b->d)

crypto/bn/bn_lib.c:449:4: 
447.   			}
448.   		else
449. > 			b = NULL;
450.   		}
451.   	

crypto/bn/bn_lib.c:453:2: 
451.   	
452.   	/* NB: bn_wexpand() calls this only if the BIGNUM really has to grow */
453. > 	A = &(b->d[b->top]);
454.   	for (i=(words - b->top)>>3; i>0; i--,A+=8)
455.   		{
