diff --git a/var/spack/repos/builtin/packages/unqlite/package.py b/var/spack/repos/builtin/packages/unqlite/package.py
index 5a92faf498d..c9ed2543d02 100644
--- a/var/spack/repos/builtin/packages/unqlite/package.py
+++ b/var/spack/repos/builtin/packages/unqlite/package.py
@@ -18,6 +18,7 @@ class Unqlite(CMakePackage):
     version("master", branch="master")
     version("1.1.9", sha256="33d5b5e7b2ca223942e77d31112d2e20512bc507808414451c8a98a7be5e15c0")
 
+    depends_on("cxx", type="build")  # generated
     depends_on("c", type="build")  # generated
 
     # This patch corresponds to https://github.com/symisc/unqlite/pull/99