Check instead of relying on NOTREACHED

NOTREACHED was designed for traditional lint decades ago,
and _Noreturn now normally subsumes its function.
In the one case in Emacs where NORETURN might help and _Noreturn does
not, check for NOTREACHED instead of assuming it.
* lib-src/etags.c (main):
* src/xterm.c (x_connection_closed):
Remove NOTREACHED after a call to a _Noreturn function, as NOTREACHED
is no longer needed there.  Also, one of the NOTREACHEDs was
misplaced, which defeated traditional lint checking anyway.
* lib-src/pop.c (pop_getline): Redo so as to not need NOTREACHED.
* src/emacs.c (main): Use eassume (false) rather than NOTREACHED,
so that running with ENABLE_CHECKING catches any internal error
causing the toplevel Frecursive_edit to return.

2 files changed, 1 insertions, 3 deletions

diff --git a/src/emacs.c b/src/emacs.c
index cc5818393a3..53572d7f0c8 100644
--- a/src/emacs.c
+++ b/src/emacs.c
@@ -2084,8 +2084,7 @@ Using an Emacs configured with --with-x-toolkit=lucid does not have this problem
 
   /* Enter editor command loop.  This never returns.  */
   Frecursive_edit ();
-  /* NOTREACHED */
-  return 0;
+  eassume (false);
 }
 
 /* Sort the args so we can find the most important ones
diff --git a/src/xterm.c b/src/xterm.c
index 0d224063d76..b761eaf4d11 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -10044,7 +10044,6 @@ For details, see etc/PROBLEMS.\n",
     {
       fprintf (stderr, "%s\n", error_msg);
       Fkill_emacs (make_fixnum (70));
-      /* NOTREACHED */
     }
 
   totally_unblock_input ();