diff --git a/lib/spack/spack/test/concretization/flag_mixing.py b/lib/spack/spack/test/concretization/flag_mixing.py
index 29899a98f18..281b5122afe 100644
--- a/lib/spack/spack/test/concretization/flag_mixing.py
+++ b/lib/spack/spack/test/concretization/flag_mixing.py
@@ -10,6 +10,7 @@
 import spack.environment as ev
 import spack.paths
 import spack.repo
+import spack.spec
 import spack.util.spack_yaml as syaml
 
 """
@@ -100,8 +101,8 @@ def test_pkg_flags_from_compiler_and_none(concretize_scope, mock_packages):
     conf_str = _compiler_cfg_one_entry_with_cflags("-Wall")
     update_concretize_scope(conf_str, "compilers")
 
-    s1 = Spec("cmake%gcc@12.100.100")
-    s2 = Spec("cmake-client^cmake%clang")
+    s1 = spack.spec.Spec("cmake%gcc@12.100.100")
+    s2 = spack.spec.Spec("cmake-client^cmake%clang")
     concrete = dict(spack.concretize.concretize_together([(s1, None), (s2, None)]))
 
     assert concrete[s1].compiler_flags["cflags"] == ["-Wall"]