diff --git a/lib/spack/spack/concretize.py b/lib/spack/spack/concretize.py
index 044dbe5fb2a..136a9d67f0f 100644
--- a/lib/spack/spack/concretize.py
+++ b/lib/spack/spack/concretize.py
@@ -339,7 +339,8 @@ def _proper_compiler_style(cspec, aspec):
                         other_compiler
                     )
                     self.concretize_version(cpkg_spec)
-                    spec.compiler.versions = cpkg_spec.versions
+                    spec.compiler = spack.spec.CompilerSpec(
+                        other_compiler.name, cpkg_spec.versions)
                     return True
                 else:
                     # No compiler with a satisfactory spec was found