Index: src/of_asprintf.m
==================================================================
--- src/of_asprintf.m
+++ src/of_asprintf.m
@@ -108,11 +108,11 @@
 			return -1;
 
 		length = vsnprintf(*string, bufferLength - 1, format,
 		    arguments);
 
-		if (length > 0 && (size_t)length < bufferLength - 1)
+		if (length >= 0 && (size_t)length < bufferLength - 1)
 			break;
 
 		if (bufferLength > INT_MAX / 2) {
 			free(*string);
 			return -1;