We need to clone submodules on Travis CI.

svenpanne · svenpanne · commit 96261466878a · 2019-01-12T23:35:32.000+01:00
diff --git a/.travis.yml b/.travis.yml
@@ -8,7 +8,7 @@ language: c
 sudo: false
 
 git:
-  submodules: false  # whether to recursively clone submodules
+  submodules: true  # whether to recursively clone submodules
 
 cache:
   directories:
