diff --git a/gsl.spec b/gsl.spec
index bad9e33..24255bb 100644
--- a/gsl.spec
+++ b/gsl.spec
@@ -42,7 +42,7 @@ mv THANKS.aux THANKS
 
 %build
 # disable FMA
-%ifarch aarch64 ppc64 ppc64le s390 s390x
+%ifarch aarch64 ppc64 ppc64le s390 s390x x86_64
 export CFLAGS="%{optflags} -ffp-contract=off"
 %endif
 %configure