--- a/src/espeak-ng.c	2021-08-03 20:34:16.970088987 +0800
+++ b/src/espeak-ng.c	2021-08-03 20:34:06.581921729 +0800
@@ -115,7 +115,7 @@ static const char *help_text =
     "\t   If <language> is omitted, then list all voices.\n"
     "-h, --help Show this help.\n";

-int samplerate;
+static int samplerate;
 int quiet = 0;
 unsigned int samples_total = 0;
 unsigned int samples_split = 0;