diff
--- a/jpc_dec.c
+++ b/jpc_dec.c
@@ -45,6 +45,9 @@
 45 	dec->numhtiles = JPC_CEILDIV(dec->xend - dec->tilexoff, dec->tilewidth);
 46 	dec->numvtiles = JPC_CEILDIV(dec->yend - dec->tileyoff, dec->tileheight);
 47 	dec->numtiles = dec->numhtiles * dec->numvtiles;
+
+	assert(dec->numtiles <= INT_MAX); // Assert that the result doesn't overflow
+
 