After swapping the order of the free and the alloc of the leafentry, I messed...

After swapping the order of the free and the alloc of the leafentry, I messed up because the alloc might move the leafentry, so the leafentry's size must be computed while the pointer is still good.  Fixes #881.

git-svn-id: file:///svn/tokudb@4276 c7de825b-a66e-492c-adef-691d508d4ae1

newbrt/brt.c

@@ -1405,12 +1405,15 @@ static int brt_leaf_apply_cmd_once (BRT t, BRTNODE node, BRT_CMD cmd, TOKULOGGER
 	node->u.l.n_bytes_in_buffer -= OMT_ITEM_OVERHEAD + leafentry_disksize(le);
 	node->local_fingerprint     -= node->rand4fingerprint * toku_le_crc(le);
 	
+	u_int32_t size = leafentry_memsize(le);
+
 	LEAFENTRY new_le = mempool_malloc_from_omt(node->u.l.buffer, &node->u.l.buffer_mempool, newlen);
 	assert(new_le);
 	memcpy(new_le, newdata, newlen);
 
 	// This mfree must occur after the mempool_malloc so that when the mempool is compressed everything is accounted for.
-	toku_mempool_mfree(&node->u.l.buffer_mempool, 0, leafentry_memsize(le)); // Must pass 0, since le may be no good any more.
+	// But we must compute the size before doing the mempool malloc because otherwise the le pointer is no good.
+	toku_mempool_mfree(&node->u.l.buffer_mempool, 0, size); // Must pass 0, since le may be no good any more.
 	
 	node->u.l.n_bytes_in_buffer += OMT_ITEM_OVERHEAD + newdisksize;
 	node->local_fingerprint += node->rand4fingerprint*toku_le_crc(newdata);