diff --git a/ghc.spec b/ghc.spec
index ac1fa22..dba5ee0 100644
--- a/ghc.spec
+++ b/ghc.spec
@@ -343,7 +343,9 @@ export LDFLAGS="${LDFLAGS:-%__global_ldflags}"
 
 # avoid "ghc: hGetContents: invalid argument (invalid byte sequence)"
 export LANG=en_US.utf8
+%if %{defined _smp_mflags}
 echo %{?_smp_mflags}
+%endif
 %ifarch %{ix86} x86_64
 %global _smp_mflags -j16
 %endif