diff --git a/podofo.spec b/podofo.spec
index 83e004f..4da2cac 100644
--- a/podofo.spec
+++ b/podofo.spec
@@ -72,7 +72,7 @@ rm cmake/modules/FindZLIB.cmake
 
 %build
 %cmake -DPODOFO_BUILD_SHARED=1 \
-%if %{__isa_bits} == 64
+%if 0%{?__isa_bits} == 64
 -DWANT_LIB64=1 \
 %endif
 .