diff --git a/gnu/packages/virtualization.scm b/gnu/packages/virtualization.scm
index e9bf459eeee..0a61e4403ed 100644
--- a/gnu/packages/virtualization.scm
+++ b/gnu/packages/virtualization.scm
@@ -694,7 +694,7 @@ domains, their live performance and resource utilization statistics.")
              ;; The includes for libnl are located in a sub-directory.
              (setenv "C_INCLUDE_PATH"
                      (string-append (assoc-ref inputs "libnl")
-                                    "/include/libnl3"
+                                    "/include/libnl3:"
                                     ;; Also add the kernel headers here so that GCC
                                     ;; treats them as "system headers".  Otherwise
                                     ;; the build fails with -Werror because parasite.c