Use standard __VA_OPT__ instead of GNU's ##__VA_ARGS__

C23 has standardized a way to write variadic macros that accept
zero arguments:
https://open-std.org/JTC1/SC22/WG14/www/docs/n3033.htm

Use that instead of the GNU extension when available.

include/backend/drm/drm.h

@@ -220,9 +220,20 @@ void drm_page_flip_destroy(struct wlr_drm_page_flip *page_flip);
 struct wlr_drm_layer *get_drm_layer(struct wlr_drm_backend *drm,
 	struct wlr_output_layer *layer);
 
+#if __STDC_VERSION__ >= 202311L
+
+#define wlr_drm_conn_log(conn, verb, fmt, ...) \
+	wlr_log(verb, "connector %s: " fmt, conn->name __VA_OPT__(,) __VA_ARGS__)
+#define wlr_drm_conn_log_errno(conn, verb, fmt, ...) \
+	wlr_log_errno(verb, "connector %s: " fmt, conn->name __VA_OPT(,) __VA_ARGS__)
+
+#else
+
 #define wlr_drm_conn_log(conn, verb, fmt, ...) \
 	wlr_log(verb, "connector %s: " fmt, conn->name, ##__VA_ARGS__)
 #define wlr_drm_conn_log_errno(conn, verb, fmt, ...) \
 	wlr_log_errno(verb, "connector %s: " fmt, conn->name, ##__VA_ARGS__)
 
 #endif
+
+#endif

include/render/vulkan.h

@@ -515,7 +515,16 @@ void vulkan_change_layout(VkCommandBuffer cb, VkImage img,
 	VkImageLayout ol, VkPipelineStageFlags srcs, VkAccessFlags srca,
 	VkImageLayout nl, VkPipelineStageFlags dsts, VkAccessFlags dsta);
 
+#if __STDC_VERSION__ >= 202311L
+
+#define wlr_vk_error(fmt, res, ...) wlr_log(WLR_ERROR, fmt ": %s (%d)", \
+	vulkan_strerror(res), res __VA_OPT(,) __VA_ARGS__)
+
+#else
+
 #define wlr_vk_error(fmt, res, ...) wlr_log(WLR_ERROR, fmt ": %s (%d)", \
 	vulkan_strerror(res), res, ##__VA_ARGS__)
 
+#endif
+
 #endif // RENDER_VULKAN_H

include/wlr/util/log.h

@@ -64,13 +64,23 @@ void _wlr_vlog(enum wlr_log_importance verbosity, const char *format, va_list ar
 #define _WLR_FILENAME __FILE__
 #endif
 
-#define wlr_log(verb, fmt, ...) \
-	_wlr_log(verb, "[%s:%d] " fmt, _WLR_FILENAME, __LINE__, ##__VA_ARGS__)
-
 #define wlr_vlog(verb, fmt, args) \
 	_wlr_vlog(verb, "[%s:%d] " fmt, _WLR_FILENAME, __LINE__, args)
 
+#if __STDC_VERSION__ >= 202311L
+
+#define wlr_log(verb, fmt, ...) \
+	_wlr_log(verb, "[%s:%d] " fmt, _WLR_FILENAME, __LINE__ __VA_OPT__(,) __VA_ARGS__)
+#define wlr_log_errno(verb, fmt, ...) \
+	wlr_log(verb, fmt ": %s" __VA_OPT__(,) __VA_ARGS__, strerror(errno))
+
+#else
+
+#define wlr_log(verb, fmt, ...) \
+	_wlr_log(verb, "[%s:%d] " fmt, _WLR_FILENAME, __LINE__, ##__VA_ARGS__)
 #define wlr_log_errno(verb, fmt, ...) \
 	wlr_log(verb, fmt ": %s", ##__VA_ARGS__, strerror(errno))
 
 #endif
+
+#endif