[gtk/macos-ci: 6/9] ci: Fix the harfbuzz build on MacOS

[Matthias Clasen <matthiasc src gnome org>]

commit 22cdee5e7f68ca7787aadf7ff169c6c70087ff5b
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Jan 3 13:13:27 2021 -0500

    ci: Fix the harfbuzz build on MacOS
    
    We need to force c++11 at the toplevel here, since
    meson can't deal with per-project compiler choice.

 .gitlab-ci.yml | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index fe9acfee03..05a636f531 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -160,6 +160,7 @@ macos:
   script:
     - meson -Dx11-backend=false
             -Dintrospection=disabled
+            -Dcpp_std=c++11
             _build
     - ninja -C _build
   artifacts: