Disable the "v-string in use/require is non-portable" warning (again).

Upstream change 32910, Debian bug #479863

diff --git a/ext/B/B/Deparse.pm b/ext/B/B/Deparse.pm
index 77ae15f..7092830 100644
--- a/ext/B/B/Deparse.pm
+++ b/ext/B/B/Deparse.pm
@@ -1456,7 +1456,6 @@ sub declare_hints {
 my %ignored_hints = (
     'open<' => 1,
     'open>' => 1,
-    'v_string' => 1,
     );
 
 sub declare_hinthash {
diff --git a/pod/perldiag.pod b/pod/perldiag.pod
index 1dd79a3..29d3cd6 100644
--- a/pod/perldiag.pod
+++ b/pod/perldiag.pod
@@ -4935,18 +4935,6 @@ the version number.
 (W misc) The version string contains invalid characters at the end, which
 are being ignored.
 
-=item v-string in use/require is non-portable
-
-(W portable) The use of v-strings is non-portable to older, pre-5.6, Perls.
-If you want your scripts to be backward portable, use the floating
-point version number: for example, instead of C<use 5.6.1> say
-C<use 5.006_001>. This of course won't make older Perls suddenly start
-understanding newer features, but at least they will show a sensible
-error message indicating the required minimum version.
-
-This warning is suppressed if the C<use 5.x.y> is preceded by a
-C<use 5.006> (see C<use VERSION> in L<perlfunc/use>).
-
 =item Warning: something's wrong
 
 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
diff --git a/pod/perlfunc.pod b/pod/perlfunc.pod
index a779b3b..d64e7a1 100644
--- a/pod/perlfunc.pod
+++ b/pod/perlfunc.pod
@@ -6855,22 +6855,16 @@ of perl older than the specified one.
 
 Specifying VERSION as a literal of the form v5.6.1 should generally be
 avoided, because it leads to misleading error messages under earlier
-versions of Perl that do not support this syntax.  The equivalent numeric
-version should be used instead.
-
-Alternatively, you can use a numeric version C<use 5.006> followed by a
-v-string version like C<use v5.10.1>, to avoid the unintuitive C<use
-5.010_001>. (older perl versions fail gracefully at the first C<use>,
-later perl versions understand the v-string syntax in the second).
+versions of Perl (that is, prior to 5.6.0) that do not support this
+syntax.  The equivalent numeric version should be used instead.
 
     use v5.6.1;		# compile time version check
     use 5.6.1;		# ditto
     use 5.006_001;	# ditto; preferred for backwards compatibility
-    use 5.006; use 5.6.1;	# ditto, for compatibility and readability
 
 This is often useful if you need to check the current Perl version before
-C<use>ing library modules that have changed in incompatible ways from
-older versions of Perl.  (We try not to do this more than we have to.)
+C<use>ing library modules that won't work with older versions of Perl.
+(We try not to do this more than we have to.)
 
 Also, if the specified perl version is greater than or equal to 5.9.5,
 C<use VERSION> will also load the C<feature> pragma and enable all
diff --git a/pp_ctl.c b/pp_ctl.c
index 64157f3..7a377f0 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -3076,14 +3076,6 @@ PP(pp_require)
 
     sv = POPs;
     if ( (SvNIOKp(sv) || SvVOK(sv)) && PL_op->op_type != OP_DOFILE) {
-	if ( SvVOK(sv) && ckWARN(WARN_PORTABLE) ) {	/* require v5.6.1 */
-	    HV * hinthv = GvHV(PL_hintgv);
-	    SV ** ptr = NULL;
-	    if (hinthv) ptr = hv_fetchs(hinthv, "v_string", FALSE);
-	    if ( !(ptr && *ptr && SvIOK(*ptr) && SvIV(*ptr)) )
-		Perl_warner(aTHX_ packWARN(WARN_PORTABLE),
-                        "v-string in use/require non-portable");
-	}
 	sv = new_version(sv);
 	if (!sv_derived_from(PL_patchlevel, "version"))
 	    upg_version(PL_patchlevel, TRUE);
@@ -3135,26 +3127,14 @@ PP(pp_require)
 
         /* We do this only with use, not require. */
 	if (PL_compcv &&
-	  /* If we request a version >= 5.6.0, then v-string are OK
-	     so set $^H{v_string} to suppress the v-string warning */
-	    vcmp(sv, sv_2mortal(upg_version(newSVnv(5.006), FALSE))) >= 0) {
-	  HV * hinthv = GvHV(PL_hintgv);
-	  if( hinthv ) {
-	      SV *hint = newSViv(1);
-	      (void)hv_stores(hinthv, "v_string", hint);
-	      /* This will call through to Perl_magic_sethint() which in turn
-		 sets PL_hints correctly.  */
-	      SvSETMAGIC(hint);
-	  }
 	  /* If we request a version >= 5.9.5, load feature.pm with the
 	   * feature bundle that corresponds to the required version. */
-	  if (vcmp(sv, sv_2mortal(upg_version(newSVnv(5.009005), FALSE))) >= 0) {
+		vcmp(sv, sv_2mortal(upg_version(newSVnv(5.009005), FALSE))) >= 0) {
 	    SV *const importsv = vnormal(sv);
 	    *SvPVX_mutable(importsv) = ':';
 	    ENTER;
 	    Perl_load_module(aTHX_ 0, newSVpvs("feature"), NULL, importsv, NULL);
 	    LEAVE;
-	  }
 	}
 
 	RETPUSHYES;
diff --git a/t/lib/warnings/pp_ctl b/t/lib/warnings/pp_ctl
index 923d54c..afaf0a7 100644
--- a/t/lib/warnings/pp_ctl
+++ b/t/lib/warnings/pp_ctl
@@ -222,18 +222,6 @@ EXPECT
 Use of uninitialized value $foo in print at (eval 1) line 1.
 ########
 # pp_ctl.c
-use warnings 'portable';
-eval 'use 5.6.1';
-EXPECT
-v-string in use/require non-portable at (eval 1) line 2.
-########
-# pp_ctl.c
-use warnings 'portable';
-eval 'use v5.6.1';
-EXPECT
-v-string in use/require non-portable at (eval 1) line 2.
-########
-# pp_ctl.c
 use warnings;
 {
     no warnings;
@@ -245,15 +233,3 @@ EXPECT
 use warnings;
 eval 'use 5.006; use 5.10.0';
 EXPECT
-########
-# pp_ctl.c
-use warnings;
-eval '{use 5.006;} use 5.10.0';
-EXPECT
-v-string in use/require non-portable at (eval 1) line 2.
-########
-# pp_ctl.c
-use warnings;
-eval 'use vars; use 5.10.0';
-EXPECT
-v-string in use/require non-portable at (eval 1) line 2.