[inseperable changes from patch from perl-5.003_95 to perl-5.003_86]

[editor's note: this commit was prepared manually so may differ in
minor ways to other inseperable changes commits]

 CORE LANGUAGE CHANGES

  Title:  "Support $ENV{PERL5OPT}"
   From:  Chip Salzenberg
  Files:  perl.c pod/perldiag.pod pod/perldelta.pod pod/perlrun.pod

  Title:  "Implement void context, in which C<wantarray> is undef"
   From:  Chip Salzenberg
  Files:  cop.h doop.c dump.c global.sym gv.c op.c op.h perl.c
          pod/perlcall.pod pod/perldelta.pod pod/perlfunc.pod
          pod/perlguts.pod pod/perlsub.pod pp.c pp_ctl.c pp_hot.c
          pp_sys.c proto.h

  Title:  "Don't look up &AUTOLOAD in @ISA when calling plain function"
   From:  Chip Salzenberg
  Files:  global.sym gv.c lib/Text/ParseWords.pm pod/perldelta.pod
          pp_hot.c proto.h t/op/method.t

  Title:  "Allow closures to be constant subroutines"
   From:  Chip Salzenberg
  Files:  op.c

  Title:  "Make C<scalar(reverse)> mean C<scalar(reverse $_)>"
   From:  Chip Salzenberg
  Files:  pp.c

  Title:  "Fix lexical suicide from C<my $x = $x> in sub"
   From:  Chip Salzenberg
  Files:  op.c

  Title:  "Make "Unrecog. char." fatal, and update its doc"
   From:  Chip Salzenberg
  Files:  pod/perldiag.pod toke.c

 CORE PORTABILITY

  Title:  "safefree() mismatch"
   From:  Roderick Schertler
 Msg-ID:  <21338.859653381@eeyore.ibcinc.com>
   Date:  Sat, 29 Mar 1997 11:36:21 -0500
  Files:  util.c

    (applied based on p5p patch as commit id 9b9b466fb02dc96c81439bafbb3b2da55238cfd2)

  Title:  "Win32 update (seven patches)"
   From:  Gurusamy Sarathy and Nick Ing-Simmons
  Files:  EXTERN.h MANIFEST win32/Makefile win32/perl.mak
          win32/perl.rc win32/perldll.mak win32/makedef.pl
          win32/modules.mak win32/win32io.c win32/bin/pl2bat.bat

 OTHER CORE CHANGES

  Title:  "Report PERL* environment variables in -V and perlbug"
   From:  Chip Salzenberg
  Files:  perl.c utils/perlbug.PL

  Title:  "Typo in perl.c: Printing NO_EMBED for perl -V"
   From:  Gisle Aas
 Msg-ID:  <199703301922.VAA13509@furubotn.sn.no>
   Date:  Sun, 30 Mar 1997 21:22:11 +0200
  Files:  perl.c

    (applied based on p5p patch as commit id b6c639e4b1912ad03b9b10ba9518d96bd0a6cfaf)

  Title:  "Don't let C<$var = $var> untaint $var"
   From:  Chip Salzenberg
  Files:  pp_hot.c pp_sys.c sv.h t/op/taint.t

  Title:  "Fix autoviv bug in C<my $x; ++$x->{KEY}>"
   From:  Chip Salzenberg
  Files:  pp_hot.c

  Title:  "Re: 5.004's new srand() default seed"
   From:  Hallvard B Furuseth
 Msg-ID:  <199703302219.AAA20998@bombur2.uio.no>
   Date:  Mon, 31 Mar 1997 00:19:13 +0200 (MET DST)
  Files:  pp.c

    (applied based on p5p patch as commit id d7d933a26349f945f93b2f0dbf85b773d8ca3219)

  Title:  "Re: embedded perl and top_env problem "
   From:  Gurusamy Sarathy
 Msg-ID:  <199703280031.TAA05711@aatma.engin.umich.edu>
   Date:  Thu, 27 Mar 1997 19:31:42 -0500
  Files:  gv.c interp.sym perl.c perl.h pp_ctl.c pp_sys.c scope.h util.c

    (applied based on p5p patch as commit id f289f7d2518e7a8a82114282e774adf50fa6ce85)

  Title:  "Define and use new macro: boolSV()"
   From:  Tim Bunce
  Files:  gv.c lib/ExtUtils/typemap os2/os2.c pp.c pp_hot.c pp_sys.c
          sv.c sv.h universal.c vms/vms.c

  Title:  "Re: strict @F"
   From:  Hallvard B Furuseth
 Msg-ID:  <199703252110.WAA16038@bombur2.uio.no>
   Date:  Tue, 25 Mar 1997 22:10:33 +0100 (MET)
  Files:  toke.c

    (applied based on p5p patch as commit id dfd44a5c8c8dd4c001c595debfe73d011a96d844)

  Title:  "Try harder to identify errors at EOF"
   From:  Chip Salzenberg
  Files:  toke.c

  Title:  "Minor string change in toke.c: 'bareword'"
   From:  lvirden@cas.org
 Msg-ID:  <1997Mar27.130247.1911552@hmivax.humgen.upenn.edu>
   Date:  Thu, 27 Mar 1997 13:02:46 -0500 (EST)
  Files:  toke.c

    (applied based on p5p patch as commit id 9b56c8f8085a9e773ad87c6b3c1d0b5e39dbc348)

  Title:  "Improve diagnostic on \r in program text"
   From:  Chip Salzenberg
  Files:  pod/perldiag.pod toke.c

  Title:  "Make Sock_size_t typedef work right"
   From:  Chip Salzenberg
  Files:  perl.h pp_sys.c

 LIBRARY AND EXTENSIONS

  Title:  "New module constant.pm"
   From:  Tom Phoenix
  Files:  MANIFEST lib/constant.pm op.c pp.c t/pragma/constant.t

  Title:  "Remove chat2"
   From:  Chip Salzenberg
  Files:  MANIFEST lib/chat2.inter lib/chat2.pl

  Title:  "Include CGI.pm 2.32"
   From:  Chip Salzenberg
  Files:  MANIFEST eg/cgi/* lib/CGI.pm lib/CGI/Apache.pm
          lib/CGI/Carp.pm lib/CGI/Fast.pm lib/CGI/Push.pm
          lib/CGI/Switch.pm

 UTILITIES

  Title:  "Tom C's Pod::Html and html tools, as of 30 March 97"
   From:  Chip Salzenberg
  Files:  MANIFEST installhtml lib/Pod/Html.pm pod/pod2html.PL

  Title:  "Fix path bugs in installhtml"
   From:  Robin Barker <rmb1@cise.npl.co.uk>
 Msg-ID:  <3180.9703270906@tempest.cise.npl.co.uk>
   Date:  Thu, 27 Mar 97 09:06:14 GMT
  Files:  installhtml

  Title:  "Make perlbug say that it's only for core Perl bugs"
   From:  Chip Salzenberg
  Files:  utils/perlbug.PL

 DOCUMENTATION

  Title:  "Document autouse and constant; update diagnostics"
   From:  Chip Salzenberg
  Files:  pod/perldelta.pod

  Title:  "Suggest to upgraders that they try '-w' again"
   From:  Hallvard B Furuseth
 Msg-ID:  <199703251901.UAA15982@bombur2.uio.no>
   Date:  Tue, 25 Mar 1997 20:01:26 +0100 (MET)
  Files:  pod/perldelta.pod

    (applied based on p5p patch as commit id 4176c059b9ba6b022e99c44270434a5c3e415b73)

  Title:  "Improve and update documentation of constant subs"
   From:  Tom Phoenix <rootbeer@teleport.com>
 Msg-ID:  <Pine.GSO.3.96.970331122546.14185C-100000@kelly.teleport.com>
   Date:  Mon, 31 Mar 1997 13:05:54 -0800 (PST)
  Files:  pod/perlsub.pod

  Title:  "Improve documentation of C<return>"
   From:  Chip Salzenberg
  Files:  pod/perlfunc.pod pod/perlsub.pod

  Title:  "perlfunc.pod patch"
   From:  Gisle Aas
 Msg-ID:  <199703262159.WAA17531@furubotn.sn.no>
   Date:  Wed, 26 Mar 1997 22:59:23 +0100
  Files:  pod/perlfunc.pod

    (applied based on p5p patch as commit id 35a731fcbcd7860eb497d6598f3f77b8746319c4)

  Title:  "Use 'while (defined($x = <>)) {}', per <gnat@frii.com>"
   From:  Chip Salzenberg
  Files:  configpm lib/Term/Cap.pm perlsh pod/perlipc.pod pod/perlop.pod
          pod/perlsub.pod pod/perlsyn.pod pod/perltrap.pod
          pod/perlvar.pod win32/bin/search.bat

  Title:  "Document and test C<%> behavior with negative operands"
   From:  Chip Salzenberg
  Files:  pod/perlop.pod t/op/arith.t

  Title:  "Update docs on $]"
   From:  Chip Salzenberg
  Files:  pod/perlvar.pod

  Title:  "perlvar.pod patch"
   From:  Gisle Aas
 Msg-ID:  <199703261254.NAA10237@bergen.sn.no>
   Date:  Wed, 26 Mar 1997 13:54:00 +0100
  Files:  pod/perlvar.pod

    (applied based on p5p patch as commit id 0aa182cb0caa3829032904b9754807b1b7418509)

  Title:  "Fix example of C<or> vs. C<||>"
   From:  Chip Salzenberg
  Files:  pod/perlsyn.pod

  Title:  "Pod usage and spelling patch"
   From:  Larry W. Virden
  Files:  pod/*.pod

  Title:  "Pod updates"
   From:  "Cary D. Renzema" <caryr@mxim.com>
 Msg-ID:  <199703262353.PAA01819@macs.mxim.com>
   Date:  Wed, 26 Mar 1997 15:53:22 -0800 (PST)
  Files:  pod/*.pod

    (applied based on p5p patch as commit id 5695b28edc67a3f45e8a0f25755d07afef3660ac)

1 files changed, 40 insertions, 0 deletions

diff --git a/scope.h b/scope.h
index d0931b1c58..d6eb270a90 100644
--- a/scope.h
+++ b/scope.h
@@ -70,3 +70,43 @@
     SSPUSHINT(SAVEt_STACK_POS);		\
  } STMT_END
 
+
+/* A jmpenv packages the state required to perform a proper non-local jump.
+ * Note that there is a start_env initialized when perl starts, and top_env
+ * points to this initially, so top_env should always be non-null.
+ *
+ * Existence of a non-null top_env->je_prev implies it is valid to call
+ * longjmp() at that runlevel (we make sure start_env.je_prev is always
+ * null to ensure this).
+ *
+ * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
+ * establish a local jmpenv to handle exception traps.  Care must be taken
+ * to restore the previous value of je_mustcatch before exiting the
+ * stack frame iff JMPENV_PUSH was not called in that stack frame.
+ * GSAR 97-03-27
+ */
+
+struct jmpenv {
+    struct jmpenv *	je_prev;
+    Sigjmp_buf		je_buf;		
+    int			je_ret;		/* return value of last setjmp() */
+    bool		je_mustcatch;	/* longjmp()s must be caught locally */
+};
+
+typedef struct jmpenv JMPENV;
+
+#define dJMPENV		JMPENV cur_env
+#define JMPENV_PUSH	(cur_env.je_prev = top_env,			\
+			 cur_env.je_ret = Sigsetjmp(cur_env.je_buf,1),	\
+			 top_env = &cur_env,				\
+			 cur_env.je_mustcatch = FALSE,			\
+			 cur_env.je_ret)
+#define JMPENV_POP	(top_env = cur_env.je_prev)
+#define JMPENV_JUMP(v)	(top_env->je_prev ? Siglongjmp(top_env->je_buf, (v))	\
+			 : ((v) == 2) ? exit(STATUS_NATIVE_EXPORT)		\
+			 : (PerlIO_printf(PerlIO_stderr(), "panic: top_env\n"),	\
+			     exit(1)))
+   
+#define CATCH_GET	(top_env->je_mustcatch)
+#define CATCH_SET(v)	(top_env->je_mustcatch = (v))
+