lock.c: work around stupid GCC 7, GCC 9 warnings

that warn about an unused return value although
it is explicitly cast to void. Use a dummy
variable and cast that to void instead...

1 files changed, 2 insertions, 1 deletions

diff --git a/lock.c b/lock.c
index 57676f89..65dc8013 100644
--- a/lock.c
+++ b/lock.c
@@ -61,7 +61,8 @@ static void unlockit(void)
 {
     if (lockfile && lock_acquired) {
 	if (unlink(lockfile)) {
-		(void)truncate(lockfile, (off_t)0);
+		int dummy = truncate(lockfile, (off_t)0);
+		(void)dummy;
 	}
     }
 }