Parenthesize macro arguments

shape.c

@@ -32,11 +32,13 @@
 
 #define REDBLACK_CACHE_SIZE (SHAPE_BUFFER_SIZE * 32)
 
+/* This depends on that the allocated memory by Ruby's allocator or
+ * mmap is not located at an odd address. */
 #define SINGLE_CHILD_TAG 0x1
-#define TAG_SINGLE_CHILD(x) (struct rb_id_table *)((uintptr_t)x | SINGLE_CHILD_TAG)
+#define TAG_SINGLE_CHILD(x) (struct rb_id_table *)((uintptr_t)(x) | SINGLE_CHILD_TAG)
 #define SINGLE_CHILD_MASK (~((uintptr_t)SINGLE_CHILD_TAG))
-#define SINGLE_CHILD_P(x) (((uintptr_t)x) & SINGLE_CHILD_TAG)
-#define SINGLE_CHILD(x) (rb_shape_t *)((uintptr_t)x & SINGLE_CHILD_MASK)
+#define SINGLE_CHILD_P(x) ((uintptr_t)(x) & SINGLE_CHILD_TAG)
+#define SINGLE_CHILD(x) (rb_shape_t *)((uintptr_t)(x) & SINGLE_CHILD_MASK)
 #define ANCESTOR_CACHE_THRESHOLD 10
 #define MAX_SHAPE_ID (SHAPE_BUFFER_SIZE - 1)
 #define ANCESTOR_SEARCH_MAX_DEPTH 2