diff --git a/var/spack/repos/builtin/packages/edm4hep/package.py b/var/spack/repos/builtin/packages/edm4hep/package.py
index a2af33d3fcc..85c1acad8ef 100644
--- a/var/spack/repos/builtin/packages/edm4hep/package.py
+++ b/var/spack/repos/builtin/packages/edm4hep/package.py
@@ -90,6 +90,8 @@ class Edm4hep(CMakePackage):
     # Corresponding changes in EDM4hep landed with https://github.com/key4hep/EDM4hep/pull/314
     extends("python", when="@0.10.6:")
 
+    conflicts("%clang@:16", when="@0.99.1:", msg="Incomplete consteval support in clang")
+
     def cmake_args(self):
         args = [
             self.define_from_variant("CMAKE_CXX_STANDARD", "cxxstd"),