Removing Y2K warnings

Message-ID: <20050407224442.GA23895@petdance.com>

p4raw-id: //depot/perl@24205

14 files changed, 17 insertions, 165 deletions

diff --git a/INSTALL b/INSTALL
index 42ce893d2b..ce6b2a6c03 100644
--- a/INSTALL
+++ b/INSTALL
@@ -332,7 +332,7 @@ after the platform hints have been run by using Configure's -A switch.
 For example, here's how to add a couple of extra flags to C compiler
 invocations:
 
-	sh Configure -Accflags="-DPERL_Y2KWARN -DPERL_POLLUTE_MALLOC"
+	sh Configure -Accflags="-DPERL_EXTERNAL_GLOB -DPERL_POLLUTE_MALLOC"
 
 For more help on Configure switches, run
 
diff --git a/MANIFEST b/MANIFEST
index 706787214e..2a4d8f5113 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -2451,7 +2451,6 @@ README.vmesa			Perl notes for VM/ESA
 README.vms			Perl notes for VMS
 README.vos			Perl notes for Stratus VOS
 README.win32			Perl notes for Windows
-README.Y2K			Notes about Year 2000 concerns
 reentr.c			Reentrant interfaces
 reentr.h			Reentrant interfaces
 reentr.pl			Reentrant interfaces
diff --git a/README.Y2K b/README.Y2K
deleted file mode 100644
index a3eb5502aa..0000000000
--- a/README.Y2K
+++ /dev/null
@@ -1,47 +0,0 @@
-The following information about Perl and the year 2000 is a modified
-version of the information that can be found in the Frequently Asked
-Question (FAQ) documents.
-
-Does Perl have a year 2000 problem?  Is Perl Y2K compliant?
-
-Short answer: No, Perl does not have a year 2000 problem.  Yes,
-       Perl is Y2K compliant (whatever that means).  The
-       programmers you've hired to use it, however, probably are
-       not.  If you want perl to complain when your programmers
-       create programs with certain types of possible year 2000
-       problems, a build option allows you to turn on warnings.
-
-Long answer: The question belies a true understanding of the
-       issue.  Perl is just as Y2K compliant as your pencil
-       --no more, and no less.  Can you use your pencil to write
-       a non-Y2K-compliant memo?  Of course you can.  Is that
-       the pencil's fault?  Of course it isn't.
-
-       The date and time functions supplied with perl (gmtime and
-       localtime) supply adequate information to determine the
-       year well beyond 2000 (2038 is when trouble strikes for
-       32-bit machines).  The year returned by these functions
-       when used in a list context is the year minus 1900.  For
-       years between 1910 and 1999 this happens to be a 2-digit
-       decimal number. To avoid the year 2000 problem simply do
-       not treat the year as a 2-digit number.  It isn't.
-
-       When gmtime() and localtime() are used in scalar context
-       they return a timestamp string that contains a fully-
-       expanded year.  For example, $timestamp =
-       gmtime(1005613200) sets $timestamp to "Tue Nov 13 01:00:00
-       2001".  There's no year 2000 problem here.
-
-       That doesn't mean that Perl can't be used to create non-
-       Y2K compliant programs.  It can.  But so can your pencil.
-       It's the fault of the user, not the language.  At the risk
-       of inflaming the NRA: ``Perl doesn't break Y2K, people
-       do.''  See http://language.perl.com/news/y2k.html for a
-       longer exposition.
-
-       If you want perl to warn you when it sees a program which
-       concatenates a number with the string "19" -- a common
-       indication of a year 2000 problem -- build perl using the
-       Configure option  "-Accflags=-DPERL_Y2KWARN".
-       (See the file INSTALL for more information about building
-       perl.)
diff --git a/lib/warnings.pm b/lib/warnings.pm
index 86e4fcee0a..635993bbd8 100644
--- a/lib/warnings.pm
+++ b/lib/warnings.pm
@@ -181,17 +181,16 @@ our %Offsets = (
     'untie'		=> 86,
     'utf8'		=> 88,
     'void'		=> 90,
-    'y2k'		=> 92,
 
     # Warnings Categories added in Perl 5.009
 
-    'assertions'	=> 94,
+    'assertions'	=> 92,
   );
 
 our %Bits = (
-    'all'		=> "\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55", # [0..47]
+    'all'		=> "\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x15", # [0..46]
     'ambiguous'		=> "\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00", # [29]
-    'assertions'	=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40", # [47]
+    'assertions'	=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10", # [46]
     'bareword'		=> "\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00\x00\x00", # [30]
     'closed'		=> "\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [6]
     'closure'		=> "\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [1]
@@ -236,13 +235,12 @@ our %Bits = (
     'untie'		=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40\x00", # [43]
     'utf8'		=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01", # [44]
     'void'		=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04", # [45]
-    'y2k'		=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10", # [46]
   );
 
 our %DeadBits = (
-    'all'		=> "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa", # [0..47]
+    'all'		=> "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\x2a", # [0..46]
     'ambiguous'		=> "\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00\x00\x00", # [29]
-    'assertions'	=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80", # [47]
+    'assertions'	=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20", # [46]
     'bareword'		=> "\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00", # [30]
     'closed'		=> "\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [6]
     'closure'		=> "\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [1]
@@ -287,11 +285,10 @@ our %DeadBits = (
     'untie'		=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x00", # [43]
     'utf8'		=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02", # [44]
     'void'		=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08", # [45]
-    'y2k'		=> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20", # [46]
   );
 
 $NONE     = "\0\0\0\0\0\0\0\0\0\0\0\0";
-$LAST_BIT = 96 ;
+$LAST_BIT = 94 ;
 $BYTES    = 12 ;
 
 $All = "" ; vec($All, $Offsets{'all'}, 2) = 3 ;
diff --git a/pod/buildtoc b/pod/buildtoc
index e4dc82ade3..7d5b01996b 100644
--- a/pod/buildtoc
+++ b/pod/buildtoc
@@ -69,7 +69,6 @@ __USAGE__
 # Don't copy these top level READMEs
 %Ignore
   = (
-     Y2K => 1,
      micro => 1,
 #     vms => 1,
      );
diff --git a/pod/perldiag.pod b/pod/perldiag.pod
index c3035a1892..675ac5278c 100644
--- a/pod/perldiag.pod
+++ b/pod/perldiag.pod
@@ -3188,11 +3188,6 @@ but there was no array C<@foo> in scope at the time. If you wanted a
 literal @foo, then write it as \@foo; otherwise find out what happened
 to the array you apparently lost track of.
 
-=item Possible Y2K bug: %s
-
-(W y2k) You are concatenating the number 19 with another number, which
-could be a potential Year 2000 problem.
-
 =item pragma "attrs" is deprecated, use "sub NAME : ATTRS" instead
 
 (D deprecated) You have written something like this:
diff --git a/pod/perllexwarn.pod b/pod/perllexwarn.pod
index 12ce1f6c82..f250fb41ef 100644
--- a/pod/perllexwarn.pod
+++ b/pod/perllexwarn.pod
@@ -298,8 +298,6 @@ The current hierarchy is:
        +- utf8
        |
        +- void
-       |
-       +- y2k
 
 Just like the "strict" pragma any of these categories can be combined
 
diff --git a/pp_hot.c b/pp_hot.c
index a8d679aef1..dcacf630aa 100644
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -178,17 +178,6 @@ PP(pp_concat)
 	    SvUTF8_off(TARG);
     }
 
-#if defined(PERL_Y2KWARN)
-    if ((SvIOK(right) || SvNOK(right)) && ckWARN(WARN_Y2K) && SvOK(TARG)) {
-	if (llen >= 2 && lpv[llen - 2] == '1' && lpv[llen - 1] == '9'
-	    && (llen == 2 || !isDIGIT(lpv[llen - 3])))
-	{
-	    Perl_warner(aTHX_ packWARN(WARN_Y2K), "Possible Y2K bug: %s",
-			"about to append an integer to '19'");
-	}
-    }
-#endif
-
     if (lbyte != rbyte) {
 	if (lbyte)
 	    sv_utf8_upgrade_nomg(TARG);
diff --git a/sv.c b/sv.c
index dff1b89d69..c476bb8c23 100644
--- a/sv.c
+++ b/sv.c
@@ -9822,19 +9822,6 @@ Perl_sv_vcatpvfn(pTHX_ SV *sv, const char *pat, STRLEN patlen, va_list *args, SV
 		}
 		break;
 	    default:		/* it had better be ten or less */
-#if defined(PERL_Y2KWARN)
-		if (ckWARN(WARN_Y2K)) {
-		    STRLEN n;
-		    char *s = SvPV(sv,n);
-		    if (n >= 2 && s[n-2] == '1' && s[n-1] == '9'
-			&& (n == 2 || !isDIGIT(s[n-3])))
-		    {
-			Perl_warner(aTHX_ packWARN(WARN_Y2K),
-				    "Possible Y2K bug: %%%c %s",
-				    c, "format string following '19'");
-		    }
-		}
-#endif
 		do {
 		    dig = uv % base;
 		    *--eptr = '0' + dig;
diff --git a/t/lib/warnings/pp_hot b/t/lib/warnings/pp_hot
index f5a580337c..070aaf0aa5 100644
--- a/t/lib/warnings/pp_hot
+++ b/t/lib/warnings/pp_hot
@@ -44,9 +44,6 @@
   Deep recursion on anonymous subroutine 	[Perl_sub_crush_depth]
     $a = sub { &$a if $a++ < 200} &$a
 
-  Possible Y2K bug: about to append an integer to '19' [pp_concat]
-    $x     = "19$yy\n";
-
   Use of reference "%s" as array index [pp_aelem]
     $x[\1]
 
@@ -275,32 +272,6 @@ Use of uninitialized value $x in concatenation (.) or string at - line 6.
 Use of uninitialized value $y in concatenation (.) or string at - line 7.
 Use of uninitialized value $y in concatenation (.) or string at - line 8.
 ########
-# pp_hot.c [pp_concat]
-use warnings 'y2k';
-use Config;
-BEGIN {
-    unless ($Config{ccflags} =~ /Y2KWARN/) {
-	print "SKIPPED\n# perl not built with -DPERL_Y2KWARN";
-	exit 0;
-    }
-}
-my $x;
-my $yy = 78;
-$x     = "19$yy\n";
-$x     = "19" . $yy . "\n";
-$x     = "319$yy\n";
-$x     = "319" . $yy . "\n";
-$yy = 19;
-$x     = "ok $yy\n";
-$yy = 9;
-$x     = 1 . $yy;
-no warnings 'y2k';
-$x     = "19$yy\n";
-$x     = "19" . $yy . "\n";
-EXPECT
-Possible Y2K bug: about to append an integer to '19' at - line 12.
-Possible Y2K bug: about to append an integer to '19' at - line 13.
-########
 # pp_hot.c [pp_aelem]
 {
 use warnings 'misc';
diff --git a/t/lib/warnings/sv b/t/lib/warnings/sv
index 1276ee056e..a9636e0cf7 100644
--- a/t/lib/warnings/sv
+++ b/t/lib/warnings/sv
@@ -32,8 +32,6 @@
 
   Undefined value assigned to typeglob
 
-  Possible Y2K bug: %d format string following '19'
-
   Reference is already weak			[Perl_sv_rvweaken] <<TODO
 
   Mandatory Warnings
@@ -317,40 +315,6 @@ EXPECT
 Undefined value assigned to typeglob at - line 3.
 ########
 # sv.c
-use warnings 'y2k';
-use Config;
-BEGIN {
-    unless ($Config{ccflags} =~ /Y2KWARN/) {
-	print "SKIPPED\n# perl not built with -DPERL_Y2KWARN";
-	exit 0;
-    }
-    $|=1;
-}
-my $x;
-my $yy = 78;
-$x     = printf  "19%02d\n", $yy;
-$x     = sprintf "#19%02d\n", $yy;
-$x     = printf  " 19%02d\n", 78;
-$x     = sprintf "19%02d\n", 78;
-$x     = printf  "319%02d\n", $yy;
-$x     = sprintf "319%02d\n", $yy;
-no warnings 'y2k';
-$x     = printf  "19%02d\n", $yy;
-$x     = sprintf "19%02d\n", $yy;
-$x     = printf  "19%02d\n", 78;
-$x     = sprintf "19%02d\n", 78;
-EXPECT
-Possible Y2K bug: %d format string following '19' at - line 16.
-Possible Y2K bug: %d format string following '19' at - line 13.
-1978
-Possible Y2K bug: %d format string following '19' at - line 14.
-Possible Y2K bug: %d format string following '19' at - line 15.
- 1978
-31978
-1978
-1978
-########
-# sv.c
 use warnings 'numeric' ;
 $a = "\x{100}\x{200}" * 42;
 no warnings 'numeric' ;
diff --git a/t/op/caller.t b/t/op/caller.t
index c97191b14a..4d90aeafd3 100644
--- a/t/op/caller.t
+++ b/t/op/caller.t
@@ -67,21 +67,23 @@ ok( $c[4], "hasargs true with unknown sub" );
 
 sub testwarn {
     my $w = shift;
-    is( (caller(0))[9], $w, "warnings");
+    is( (caller(0))[9], $w, "warnings match caller");
 }
 
 # NB : extend the warning mask values below when new warnings are added
 {
     no warnings;
-    BEGIN { is( ${^WARNING_BITS}, "\0" x 12, 'warning bits' ) }
+    BEGIN { is( ${^WARNING_BITS}, "\0" x 12, 'all bits off via "no warnings"' ) }
     testwarn("\0" x 12);
+
     use warnings;
-    BEGIN { is( ${^WARNING_BITS}, "U" x 12, 'warning bits' ) }
-    BEGIN { testwarn("U" x 12); }
+    BEGIN { is( ${^WARNING_BITS}, "UUUUUUUUUUU\025", 'default bits on via "use warnings"' ); }
+    BEGIN { testwarn("UUUUUUUUUUU\025", "#1"); }
     # run-time :
     # the warning mask has been extended by warnings::register
-    testwarn("UUUUUUUUUUUU\001");
+    testwarn("UUUUUUUUUUUU");
+
     use warnings::register;
-    BEGIN { is( ${^WARNING_BITS}, "UUUUUUUUUUUU\001", 'warning bits' ) }
-    testwarn("UUUUUUUUUUUU\001");
+    BEGIN { is( ${^WARNING_BITS}, "UUUUUUUUUUUU", 'warning bits on via "use warnings::register"' ) }
+    testwarn("UUUUUUUUUUUU","#3");
 }
diff --git a/warnings.h b/warnings.h
index 2798467a25..11efe1dc7e 100644
--- a/warnings.h
+++ b/warnings.h
@@ -71,11 +71,10 @@
 #define WARN_UNTIE		43
 #define WARN_UTF8		44
 #define WARN_VOID		45
-#define WARN_Y2K		46
 
 /* Warnings Categories added in Perl 5.009 */
 
-#define WARN_ASSERTIONS		47
+#define WARN_ASSERTIONS		46
 
 #define WARNsize		12
 #define WARN_ALLstring		"\125\125\125\125\125\125\125\125\125\125\125\125"
diff --git a/warnings.pl b/warnings.pl
index 43f0aa6e12..e7659b9374 100644
--- a/warnings.pl
+++ b/warnings.pl
@@ -49,7 +49,6 @@ my $tree = {
        	'misc'		=> [ 5.008, DEFAULT_OFF],
        	'regexp'	=> [ 5.008, DEFAULT_OFF],
        	'glob'		=> [ 5.008, DEFAULT_OFF],
-       	'y2k'		=> [ 5.008, DEFAULT_OFF],
        	'untie'		=> [ 5.008, DEFAULT_OFF],
 	'substr'	=> [ 5.008, DEFAULT_OFF],
 	'taint'		=> [ 5.008, DEFAULT_OFF],