diff --git a/liberty-tui.c b/liberty-tui.c
index 4d48c2a..7cc9bfb 100644
--- a/liberty-tui.c
+++ b/liberty-tui.c
@@ -194,9 +194,7 @@ row_buffer_space (struct row_buffer *self, int width, chtype attrs)
 	if (width < 0)
 		return;
 
-	while (self->chars_len + width >= self->chars_alloc)
-		self->chars = xreallocarray (self->chars,
-			sizeof *self->chars, (self->chars_alloc <<= 1));
+	ARRAY_RESERVE (self->chars, (size_t) width);
 
 	struct row_char space = { .attrs = attrs, .c = ' ', .width = 1 };
 	self->total_width += width;
diff --git a/liberty.c b/liberty.c
index 86852fd..5ed68da 100644
--- a/liberty.c
+++ b/liberty.c
@@ -305,17 +305,17 @@ xstrndup (const char *s, size_t n)
 
 // The most basic helper macros to make working with arrays not suck
 
-#define ARRAY(type, name) type *name; size_t name ## _len, name ## _size;
+#define ARRAY(type, name) type *name; size_t name ## _len, name ## _alloc;
 #define ARRAY_INIT_SIZED(a, n)                                                 \
 	BLOCK_START                                                                \
-		(a) = xcalloc (sizeof *(a), (a ## _size) = (n));                       \
+		(a) = xcalloc (sizeof *(a), (a ## _alloc) = (n));                      \
 		(a ## _len) = 0;                                                       \
 	BLOCK_END
 #define ARRAY_INIT(a) ARRAY_INIT_SIZED (a, 16)
 #define ARRAY_RESERVE(a, n)                                                    \
 	BLOCK_START                                                                \
-		while ((a ## _size) - (a ## _len) < n)                                 \
-			(a) = xreallocarray ((a), sizeof *(a), (a ## _size) <<= 1);        \
+		while ((a ## _alloc) - (a ## _len) < n)                                \
+			(a) = xreallocarray ((a), sizeof *(a), (a ## _alloc) <<= 1);       \
 	BLOCK_END
 
 // --- Double-linked list helpers ----------------------------------------------