Re: Bison message counters silently wrap around; return from 'main'

[Paul Eggert]

> From: Akim Demaille <address@hidden>
> Date: 22 Oct 2002 09:04:06 +0200
> 
> This had been a question a few months ago with Autoconf: nobody
> could recall what host could fail to exit nonzero when main does.

SunOS versions 2.0 through 3.5 have that problem.  See:

http://groups.google.com/groups?selm=758%40auspex.UUCP
http://groups.google.com/groups?selm=1992Sep10.003907.15391%40sq.sq.com

However, I agree that this is now too ancient even for Bison, so
I installed the following change.

2002-10-22  Paul Eggert  <address@hidden>

        * src/complain.c (exit) [! (STDC_HEADERS || _LIBC)]: Remove exit
        decl; not needed any more now that we assume ANSI C.
        (main): Use return to exit, undoing yesterday's change.
        The last OS that we could find where this wouldn't work is
        SunOS 3.5, and that's too old to worry about now.

Index: src/complain.c
===================================================================
RCS file: /cvsroot/bison/bison/src/complain.c,v
retrieving revision 1.15
diff -p -u -r1.15 complain.c
--- src/complain.c      22 Oct 2002 04:53:49 -0000      1.15
+++ src/complain.c      23 Oct 2002 06:56:11 -0000
@@ -29,8 +29,6 @@
 #if STDC_HEADERS || _LIBC
 # include <stdlib.h>
 # include <string.h>
-#else
-void exit ();
 #endif
 
 #include "complain.h"
Index: src/main.c
===================================================================
RCS file: /cvsroot/bison/bison/src/main.c,v
retrieving revision 1.71
diff -p -u -r1.71 main.c
--- src/main.c  22 Oct 2002 05:07:12 -0000      1.71
+++ src/main.c  23 Oct 2002 06:56:11 -0000
@@ -74,7 +74,7 @@ main (int argc, char *argv[])
   timevar_pop (TV_READER);
 
   if (complaint_issued)
-    exit (EXIT_FAILURE);
+    return EXIT_FAILURE;
 
   /* Find useless nonterminals and productions and reduce the grammar. */
   timevar_push (TV_REDUCE);
@@ -138,7 +138,7 @@ main (int argc, char *argv[])
   /* Stop if there were errors, to avoid trashing previous output
      files.  */
   if (complaint_issued)
-    exit (EXIT_FAILURE);
+    return EXIT_FAILURE;
 
   /* Lookaheads are no longer needed. */
   timevar_push (TV_FREE);
@@ -177,10 +177,5 @@ main (int argc, char *argv[])
   timevar_stop (TV_TOTAL);
   timevar_print (stderr);
 
-  /* Some ancient SunOS versions exit (0) if main returns, so use
-     `exit' to exit with nonzero status.  */
-  if (complaint_issued)
-    exit (EXIT_FAILURE);
-
-  return EXIT_SUCCESS;
+  return complaint_issued ? EXIT_FAILURE : EXIT_SUCCESS;
 }