diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index f6217c3..628058b 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -933,7 +933,7 @@
 				else
 					PyFile_WriteString(filename, f);
 				PyFile_WriteString("\", line ", f);
-				sprintf(buf, "%d", lineno);
+				PyOS_snprintf(buf, sizeof(buf), "%d", lineno);
 				PyFile_WriteString(buf, f);
 				PyFile_WriteString("\n", f);
 				if (text != NULL)