sort: fix failure if sort's parent has ignored SIGCHLD

* src/sort.c (main): Reset the SIGCHLD handler to the default
as otherwise wait() could return an error.
* tests/misc/sort-compress: Set the CHLD handler in a subshell
to SIG_IGN to ensure the sort command resets it to SIG_DFL.
* NEWS: Mention the fix.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/sort.c b/src/sort.c
index 8709e5370..70e0bbbae 100644
--- a/src/sort.c
+++ b/src/sort.c
@@ -3254,6 +3254,7 @@ main (int argc, char **argv)
         }
 #endif
   }
+  signal (SIGCHLD, SIG_DFL); /* Don't inherit CHLD handling from parent.  */
 
   /* The signal mask is known, so it is safe to invoke exit_cleanup.  */
   atexit (exit_cleanup);