From c70468b8d3c1d6711da0db84cba30d87d2482e5c Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikita.ppv@gmail.com>
Date: Mon, 28 May 2018 22:14:04 +0200
Subject: [PATCH] Add note about heredoc BC break

---
 UPGRADING | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/UPGRADING b/UPGRADING
index 50cefc8958..d38d88eac6 100644
--- a/UPGRADING
+++ b/UPGRADING
@@ -30,6 +30,20 @@ Core:
     thrown exceptions.
   . TypeError now reports wrong types as `int` and `bool` instead of `integer`
     and `boolean`.
+  . Due to the introduction of flexible heredoc/nowdoc syntax (see New Features
+    section), doc strings that contain the ending label inside their body may
+    cause syntax errors or change in interpretation. For example in
+
+        $str = <<<FOO
+        abcdefg
+            FOO
+        FOO;
+
+    the indented occurrence of "FOO" did not previously have any special
+    meaning. Now it will be interpreted as the end of the heredoc string and
+    the following "FOO;" will cause a syntax error. This issue can always be
+    resolved by choosing an ending label that does not occur within the contents
+    of the string.
 
 BCMath:
   . All warnings thrown by BCMath functions are now using PHP's error handling.
-- 
2.50.1