From 442bc2afee6c5f731c7b3e76ccab7301703a45a7 Mon Sep 17 00:00:00 2001
From: Luca Boccassi <luca.boccassi@microsoft.com>
Date: Thu, 3 Dec 2020 16:17:43 +0000
Subject: [PATCH] meson: check that cxx variable is set before using it

In some cases it is not defined. Eg in a yocto build:

src/systemd/meson.build:61:15: ERROR: Unknown variable cxx.
---
 src/systemd/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/systemd/meson.build b/src/systemd/meson.build
index c9c484b411..3d328e5fd3 100644
--- a/src/systemd/meson.build
+++ b/src/systemd/meson.build
@@ -54,7 +54,7 @@ if cc.has_argument('-std=iso9899:2017')
         opts += [['c', '-std=iso9899:2017']]
 endif
 
-if add_languages('cpp', required : false)
+if cxx_cmd != ''
         opts += [['c++'],
                  ['c++', '-std=c++98'],
                  ['c++', '-std=c++11']]