foreach(): loop variables are only available in the loop scope

Fixes: #20553

1 files changed, 20 insertions, 0 deletions

diff --git a/Help/policy/CMP0124.rst b/Help/policy/CMP0124.rst
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+CMP0124
+-------
+
+.. versionadded:: 3.21
+
+The loop variables created by :command:`foreach` command have now their scope
+restricted to the loop scope.
+
+Starting with CMake 3.21, the :command:`foreach` command ensures that the loop
+variables have their scope restricted to the loop scope.
+
+The ``OLD`` behavior for this policy let the loop variables to exist, with an
+empty value, in the outer scope of loop scope.
+
+This policy was introduced in CMake version 3.21. Use the
+:command:`cmake_policy` command to set it to ``OLD`` or ``NEW`` explicitly.
+Unlike many policies, CMake version |release| does *not* warn when the policy
+is not set and simply uses ``OLD`` behavior.
+
+.. include:: DEPRECATED.txt