diff --git a/ChangeLog b/ChangeLog
index ecd3364e..20bb91ef 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -10,6 +10,7 @@
 - added "fail" option to im_jpeg2vips: fail with an error on any warning
   (thank you Ole)
 - im_buildlut() could segv for non-zero based tables (thanks Jack)
+- VIPS_BUF_STATIC() does not take length arg
 
 25/3/09 started 7.18.0
 - revised version numbers
diff --git a/include/vips/buf.h b/include/vips/buf.h
index 45476e34..46df7029 100644
--- a/include/vips/buf.h
+++ b/include/vips/buf.h
@@ -48,8 +48,8 @@ typedef struct {
 
 /* Static init of one of these.
  */
-#define VIPS_BUF_STATIC( TEXT, MAX ) \
-	{ &TEXT[0], MAX, 0, FALSE, 0, FALSE }
+#define VIPS_BUF_STATIC( TEXT ) \
+	{ &TEXT[0], sizeof( TEXT ), 0, FALSE, 0, FALSE }
 
 /* Init and append to one of the above.
  */
diff --git a/libsrc/iofuncs/error.c b/libsrc/iofuncs/error.c
index 3a670fd0..53a8e76d 100644
--- a/libsrc/iofuncs/error.c
+++ b/libsrc/iofuncs/error.c
@@ -70,8 +70,7 @@
  */
 #define IM_MAX_ERROR (10240)
 static char im_error_text[IM_MAX_ERROR] = "";
-static VipsBuf im_error_buf = 
-	VIPS_BUF_STATIC( im_error_text, IM_MAX_ERROR );
+static VipsBuf im_error_buf = VIPS_BUF_STATIC( im_error_text );
 
 #define IM_DIAGNOSTICS "IM_DIAGNOSTICS"
 #define IM_WARNING "IM_WARNING"