Backport a test fix from upstream to fix the build

https://bugzilla.gnome.org/show_bug.cgi?id=796313

0001-tests-Drop-fatal-assert-on-big-endian-archs.patch

@@ -0,0 +1,26 @@
+From 4a76af7326bb66a3761c0d1093caff31a1541738 Mon Sep 17 00:00:00 2001
+From: Rico Tzschichholz <ricotz@ubuntu.com>
+Date: Mon, 21 May 2018 18:57:42 +0200
+Subject: [PATCH] tests: Drop fatal assert on big-endian archs
+
+The assert isn't required to verify this specific fix, but obviously shows
+another underlying issue.
+
+https://bugzilla.gnome.org/show_bug.cgi?id=796313
+---
+ tests/methods/bug634753.vala | 1 -
+ 1 file changed, 1 deletion(-)
+
+diff --git a/tests/methods/bug634753.vala b/tests/methods/bug634753.vala
+index fdee042..c33f44a 100644
+--- a/tests/methods/bug634753.vala
++++ b/tests/methods/bug634753.vala
+@@ -1,5 +1,4 @@
+ void foo ([CCode (array_length_type = "gsize")] ref uint8[] a) {
+-	assert (a.length == 32);
+ }
+ 
+ void main () {
+-- 
+1.8.3.1
+

vala.spec

@@ -10,6 +10,8 @@ Summary:        A modern programming language for GNOME
 License:        LGPLv2+ and BSD
 URL:            https://wiki.gnome.org/Projects/Vala
 Source0:        https://download.gnome.org/sources/vala/0.40/vala-%{version}.tar.xz
+# Backported from upstream
+Patch0:         0001-tests-Drop-fatal-assert-on-big-endian-archs.patch
 
 BuildRequires:  flex
 BuildRequires:  bison