From 84b32f52b10f9912b40ef378cd0b01f4aff80630 Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.be>
Date: Wed, 23 Nov 2016 22:52:36 +0100
Subject: [PATCH] Jumping into constructs will be fatal in 5.28.

---
 pod/perldeprecation.pod | 26 ++++++++++++++++++++++++++
 pod/perldiag.pod        |  4 +++-
 pod/perlfunc.pod        |  3 ++-
 pp_ctl.c                |  2 +-
 4 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/pod/perldeprecation.pod b/pod/perldeprecation.pod
index fb1d3861bd8a..13879347b971 100644
--- a/pod/perldeprecation.pod
+++ b/pod/perldeprecation.pod
@@ -151,6 +151,32 @@ will be a fatal error in Perl 5.28.
 
 You should be using two different symbols instead.
 
+
+
+=head3 Use of "goto" to jump into a construct.
+
+Use of C<goto> to jump from an outer scope into an inner scope was
+deprecated in Perl 5.12, and it will be a fatal error in Perl 5.28.
+
+This means, you should not write constructs like:
+
+   $x = 1;
+   while ($x) {
+       $foo = 1;
+     LABEL:
+       $bar = 1;
+   }
+   goto LABEL;
+
+This will jump into the block belonging to C<while>. Not only has 
+been this a cause of subtle bugs in the past, it's generally
+considered to lead to hard to understand programs.
+
+This means, soon it's not possible anymore to write
+L<Duff's device|https://www.lysator.liu.se/c/duffs-device.html> in pure Perl.
+But you never wanted to do this anyway.
+
+
 =head3 ${^ENCODING} is no longer supported.
 
 The special variable C<${^ENCODING}> was used to implement
diff --git a/pod/perldiag.pod b/pod/perldiag.pod
index 6f61d2227358..d581a630ed6a 100644
--- a/pod/perldiag.pod
+++ b/pod/perldiag.pod
@@ -6979,11 +6979,13 @@ middle of an iteration causes Perl to see a freed value.
 operator.  Since C<split> always tries to match the pattern
 repeatedly, the C</g> has no effect.
 
-=item Use of "goto" to jump into a construct is deprecated
+=item Use of "goto" to jump into a construct is deprecated. Its use will be fatal in Perl 5.28
 
 (D deprecated) Using C<goto> to jump from an outer scope into an inner
 scope is deprecated and should be avoided.
 
+This was deprecated in Perl 5.12, and will be a fatal error in Perl 5.28.
+
 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
 
 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD>
diff --git a/pod/perlfunc.pod b/pod/perlfunc.pod
index 18bb4654e1e1..d8cf052aa44e 100644
--- a/pod/perlfunc.pod
+++ b/pod/perlfunc.pod
@@ -3285,7 +3285,8 @@ Also, unlike most named operators, this has the same precedence as
 assignment.
 
 Use of C<goto LABEL> or C<goto EXPR> to jump into a construct is
-deprecated and will issue a warning.  Even then, it may not be used to
+deprecated and will issue a warning; it will be a fatal error in
+Perl 5.28. Even then, it may not be used to
 go into any construct that requires initialization, such as a
 subroutine or a C<foreach> loop.  It also can't be used to go into a
 construct that is optimized away.
diff --git a/pp_ctl.c b/pp_ctl.c
index 89a7521f603f..b86ebde544fe 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -3011,7 +3011,7 @@ PP(pp_goto)
 	if (*enterops && enterops[1]) {
 	    I32 i = enterops[1]->op_type == OP_ENTER && in_block ? 2 : 1;
 	    if (enterops[i])
-		deprecate("\"goto\" to jump into a construct");
+		deprecate_fatal_in("5.28", "Use of \"goto\" to jump into a construct is deprecated. Its use will be fatal in Perl 5.28");
 	}
 
 	/* pop unwanted frames */