diff --git a/mlpack.spec b/mlpack.spec
index 13363c8..786377c 100644
--- a/mlpack.spec
+++ b/mlpack.spec
@@ -140,7 +140,8 @@ cp %SOURCE2 stb/;
 %endif
 
 # Try and reduce RAM usage.
-cmake -D CFLAGS=`echo %{optflags} | sed 's/-pipe//g'` .
+cmake -D CFLAGS=`echo %{optflags} | sed 's/-pipe//g' | sed 's/$/--param ggc-min-heapsize=32768 --param ggc-min-expand=1/' \
+      -D CXXFLAGS=`echo %{optflags} | sed 's/-pipe//g' | sed 's/$/--param ggc-min-heapsize=32768 --param ggc-min-expand=1/' .
 
 # Don't use %make because it could use too much RAM with multiple cores on Koji...
 make