diff --git a/llvm.spec b/llvm.spec
index 6067ab1..46a2eda 100644
--- a/llvm.spec
+++ b/llvm.spec
@@ -187,9 +187,10 @@ BuildRequires: python3-pexpect
 # This is required because we need "ps" when running LLDB tests
 BuildRequires: procps-ng
 
-%if %{without compat_build}
 # For reproducible pyc file generation
 # See https://docs.fedoraproject.org/en-US/packaging-guidelines/Python_Appendix/#_byte_compilation_reproducibility
+# Since Fedora 41 this happens automatically, and RHEL 8 does not support this.
+%if (%{defined fedora} && 0%{?fedora} < 41) || 0%{?rhel} == 9 || 0%{?rhel} == 10
 BuildRequires: /usr/bin/marshalparser
 %global py_reproducible_pyc_path %{buildroot}%{python3_sitelib}
 %endif