diff --git a/petsc.spec b/petsc.spec
index 68502de..e1c6428 100644
--- a/petsc.spec
+++ b/petsc.spec
@@ -36,15 +36,14 @@
 
 %if %{?__isa_bits:%{__isa_bits}}%{!?__isa_bits:32} == 64
 %bcond_without arch64
-%bcond_without index64
 %else
 %bcond_with arch64
-%bcond_with index64
 %endif
 
 %bcond_without blas
 %if %{with arch64}
 %bcond_without blas64
+%bcond_without index64
 %endif
 
 %if 0%{?fedora} || 0%{?rhel} >= 9