diff --git a/cont.c b/cont.c
index 11428564be..9ab5a8fefe 100644
--- a/cont.c
+++ b/cont.c
@@ -495,10 +495,10 @@ static void
 fiber_set_stack_location(void)
 {
     rb_thread_t *th = GET_THREAD();
-    VALUE ptr;
+    VALUE *ptr;
 
     SET_MACHINE_STACK_END(&ptr);
-    th->machine_stack_start = (void*)((ptr & PAGE_MASK) + STACK_UPPER(&ptr, 0, PAGE_SIZE));
+    th->machine_stack_start = (void*)(((VALUE)ptr & PAGE_MASK) + STACK_UPPER(&ptr, 0, PAGE_SIZE));
 }
 
 static VOID CALLBACK
diff --git a/iseq.c b/iseq.c
index 51891b2ce1..48d0cdfcb9 100644
--- a/iseq.c
+++ b/iseq.c
@@ -229,7 +229,7 @@ prepare_iseq_build(rb_iseq_t *iseq,
     iseq->name = name;
     iseq->filename = filename;
     iseq->filepath = filepath == Qnil ? Qnil : rb_realpath_internal(Qnil, filepath, 1);
-    iseq->line_no = line_no;
+    iseq->line_no = (unsigned short)line_no; /* TODO: really enough? */
     iseq->defined_method_id = 0;
     iseq->mark_ary = rb_ary_tmp_new(3);
     OBJ_UNTRUST(iseq->mark_ary);
diff --git a/node.c b/node.c
index e7d3c4cd34..65bc541ed8 100644
--- a/node.c
+++ b/node.c
@@ -501,7 +501,7 @@ dump_node(VALUE buf, VALUE indent, int comment, NODE *node)
 	F_CUSTOM1(nd_nth, "variable", {
 	   char name[3];
 	   name[0] = '$';
-	   name[1] = node->nd_nth;
+	   name[1] = (char)node->nd_nth;
 	   name[2] = '\0';
 	   A(name);
 	});