Ah you star - that did it. I missed the -p1 part from the query. I still get this though:

patch -p1 < 0001-Fix-a-pad-problem-with-Perl-5.21.4-on-threaded-build.
+patch
can't find file to patch at input line 19
Perhaps you used the wrong -p or --strip option?
The text leading up to this was:
--------------------------
|From ba92f4cba247c91d100e05f2b83dd093055e462b Mon Sep 17 00:00:00 200
+1
|From: Niko Tyni <ntyni@debian.org>
|Date: Fri, 25 Dec 2015 18:53:08 +0200
|Subject: [PATCH] Fix a pad problem with Perl >= 5.21.4 on threaded bu
+ilds
|
|This broke at least the Kavorka and Moops distributions.
|
|Bug-Debian: https://bugs.debian.org/808826
|---
| lib/Devel/CallParser.xs | 10 +++++++---
| t/pad2.t                | 15 +++++++++++++++
| 2 files changed, 22 insertions(+), 3 deletions(-)
| create mode 100644 t/pad2.t
|
|diff --git a/lib/Devel/CallParser.xs b/lib/Devel/CallParser.xs
|index 6643739..847742c 100644
|--- a/lib/Devel/CallParser.xs
|+++ b/lib/Devel/CallParser.xs
--------------------------
File to patch:
[download]

UPDATE: Never mind, me being dumb! I was in the wrong directory, so it couldn't find the files ;)