From 6f6651f7288a8ba651a95c46bebf57fc59e6dc16 Mon Sep 17 00:00:00 2001
From: Brad King <brad.king@kitware.com>
Date: Thu, 11 Jun 2020 06:01:03 -0400
Subject: Add deprecation warnings for policies CMP0072 and below

The OLD behaviors of all policies are deprecated, but only by
documentation.  Add an explicit deprecation diagnostic for policies
introduced in CMake 3.11 and below to encourage projects to port away
from setting policies to OLD.
---
 Help/release/dev/deprecate-policy-old.rst        |  8 ++++++++
 Source/cmMakefile.cxx                            |  2 +-
 Tests/RunCMake/FindOpenGL/CMP0072-OLD-stderr.txt | 10 ++++++++++
 3 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100644 Help/release/dev/deprecate-policy-old.rst
 create mode 100644 Tests/RunCMake/FindOpenGL/CMP0072-OLD-stderr.txt

diff --git a/Help/release/dev/deprecate-policy-old.rst b/Help/release/dev/deprecate-policy-old.rst
new file mode 100644
index 0000000..f92aea7
--- /dev/null
+++ b/Help/release/dev/deprecate-policy-old.rst
@@ -0,0 +1,8 @@
+deprecate-policy-old
+--------------------
+
+* An explicit deprecation diagnostic was added for policy ``CMP0071``
+  (``CMP0071`` and below were already deprecated).
+  The :manual:`cmake-policies(7)` manual explains that the OLD behaviors
+  of all policies are deprecated and that projects should port to the
+  NEW behaviors.
diff --git a/Source/cmMakefile.cxx b/Source/cmMakefile.cxx
index c78b751..5c3063b 100644
--- a/Source/cmMakefile.cxx
+++ b/Source/cmMakefile.cxx
@@ -4554,7 +4554,7 @@ bool cmMakefile::SetPolicy(cmPolicies::PolicyID id,
 
   // Deprecate old policies, especially those that require a lot
   // of code to maintain the old behavior.
-  if (status == cmPolicies::OLD && id <= cmPolicies::CMP0071 &&
+  if (status == cmPolicies::OLD && id <= cmPolicies::CMP0072 &&
       !(this->GetCMakeInstance()->GetIsInTryCompile() &&
         (
           // Policies set by cmCoreTryCompile::TryCompileCode.
diff --git a/Tests/RunCMake/FindOpenGL/CMP0072-OLD-stderr.txt b/Tests/RunCMake/FindOpenGL/CMP0072-OLD-stderr.txt
new file mode 100644
index 0000000..68d23d4
--- /dev/null
+++ b/Tests/RunCMake/FindOpenGL/CMP0072-OLD-stderr.txt
@@ -0,0 +1,10 @@
+^CMake Deprecation Warning at CMP0072-OLD.cmake:1 \(cmake_policy\):
+  The OLD behavior for policy CMP0072 will be removed from a future version
+  of CMake.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)$
-- 
cgit v0.12


From 9710790a39e2c075eeef06ed529d568385a4f445 Mon Sep 17 00:00:00 2001
From: Brad King <brad.king@kitware.com>
Date: Fri, 12 Jun 2020 08:55:47 -0400
Subject: Help/dev: Add maintainer guide step for initial post-release
 development

Document steps for deprecating old policy settings and future-proofing
export files generated by `install(EXPORT)`.
---
 Help/dev/maint.rst | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/Help/dev/maint.rst b/Help/dev/maint.rst
index a1c1a6f..9b6774b 100644
--- a/Help/dev/maint.rst
+++ b/Help/dev/maint.rst
@@ -299,3 +299,28 @@ announcing that post-release development is open::
   before staging or merging.
 
 .. _`CMake Discourse Forum Development Category`: https://discourse.cmake.org/c/development
+
+Initial Post-Release Development
+--------------------------------
+
+Deprecate policies more than 8 release series old by updating the
+policy range check in ``cmMakefile::SetPolicy``.
+Commit with a message such as::
+
+  Add deprecation warnings for policies CMP#### and below
+
+  The OLD behaviors of all policies are deprecated, but only by
+  documentation.  Add an explicit deprecation diagnostic for policies
+  introduced in CMake $OLDVER and below to encourage projects to port
+  away from setting policies to OLD.
+
+Update the ``cmake_policy`` version range generated by ``install(EXPORT)``
+in ``cmExportFileGenerator::GeneratePolicyHeaderCode`` to end at the
+previous release.  We use one release back since we now know all the
+policies added for that version.  Commit with a message such as::
+
+  export: Increase maximum policy version in exported files to $prev
+
+  The files generatd by `install(EXPORT)` and `export()` commands
+  are known to work with policies as of CMake $prev, so enable them
+  in sufficiently new CMake versions.
-- 
cgit v0.12