File 1267-erts-Add-warning-in-erl_nif-doc-about-match-state-pr.patch of Package erlang

From a4007c0204f9b5b513a70cbf893ae0795afc4684 Mon Sep 17 00:00:00 2001
From: Sverker Eriksson <sverker@erlang.org>
Date: Wed, 27 Jan 2021 20:17:30 +0100
Subject: [PATCH] erts: Add warning in erl_nif doc about match state problem

---
 erts/doc/src/erl_nif.xml | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml
index d2a1581e35..57bff58db4 100644
--- a/erts/doc/src/erl_nif.xml
+++ b/erts/doc/src/erl_nif.xml
@@ -140,6 +140,21 @@ $> erl
         However, unused local stub functions will be optimized
         away by the compiler, causing loading of the NIF library to fail.</p>
     </note>
+    <warning>
+      <p>
+	There is a known limitation for Erlang fallback functions of NIFs. Avoid
+	functions involved in traversal of binaries by matching and
+	recursion. If a NIF is loaded over such function, binary arguments to
+	the NIF may get corrupted and cause VM crash or other misbehavior.
+      </p>
+      <p>Example of such bad fallback function:</p>
+	<code type="none">
+skip_until(Byte, &lt;&lt;Byte, Rest/binary&gt;&gt;) ->
+    Rest;
+skip_until(Byte, &lt;&lt;_, Rest/binary&gt;&gt;) ->
+    skip_until(Byte, Rest).
+</code>
+    </warning>
   </section>
 
   <section>
-- 
2.26.2