In very obscure situations we may write the free token back to the pipe.

Don't do that.  I couldn't come up with a repro case for this!

1 files changed, 2 insertions, 1 deletions

diff --git a/main.c b/main.c
index 75eb4941..d260859a 100644
--- a/main.c
+++ b/main.c
@@ -3116,7 +3116,8 @@ clean_jobserver (int status)
                "INTERNAL: Exiting with %u jobserver tokens (should be 0)!",
                jobserver_tokens);
       else
-        while (jobserver_tokens--)
+        /* Don't write back the "free" token */
+        while (--jobserver_tokens)
           {
             int r;