From 2dbd80ca95d7c095e2d256def2d170bc3616d707 Mon Sep 17 00:00:00 2001
From: Niklas Schmitz <niklas.f.schmitz@gmail.com>
Date: Wed, 24 Feb 2021 23:55:37 +0100
Subject: [PATCH] Fix rrule of sum3

---
 docs/src/writing_good_rules.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/src/writing_good_rules.md b/docs/src/writing_good_rules.md
index a59f951f5..bbbb094a9 100644
--- a/docs/src/writing_good_rules.md
+++ b/docs/src/writing_good_rules.md
@@ -274,7 +274,7 @@ function ChainRulesCore.rrule(::typeof(sum3), a)
     y = sum3(a)
     function sum3_pullback(ȳ)
         grad = zeros(length(a))
-        grad[1:3] .+= 1.0
+        grad[1:3] .+= ȳ
         return NO_FIELDS, grad
     end
     return y, sum3_pullback