diff --git a/src/Makefile.am b/src/Makefile.am
index 2359d58c..b1cfcaa5 100755
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,11 +1,12 @@
 bin_PROGRAMS = CTEM 
 #ifort optimized flags
-#AM_FCFLAGS =  -O3 -openmp -parallel -xHost -ipo -assume byterecl -m64 -heap-arrays -FR
+#AM_FCFLAGS =  -O3 -openmp -parallel -xHost -ipo -assume byterecl -m64 -heap-arrays -FR 
+AM_FCFLAGS =  -O3 -openmp -parallel -assume byterecl -m64 -heap-arrays -FR 
 #ifort debug flags
-#AM_FCFLAGS = -O0 -p -g -openmp -debug all -traceback -CB
+#AM_FCFLAGS = -O3 -p -g -openmp -debug all -traceback -CB -assume byterecl -m64 -heap-arrays -FR
 
 #gfortran optimized flags
-AM_FCFLAGS =  -O3 -fopenmp -ffree-form  -g -fbounds-check -fbacktrace
+#AM_FCFLAGS =  -O3 -fopenmp -ffree-form  -g -fbounds-check -fbacktrace
 #gfortran debug flags
 #AM_FCFLAGS =  -O0 -g -fopenmp -fbounds-check -Wall -Warray-bounds -Warray-temporaries -Wimplicit-interface -ffree-form
 
@@ -79,6 +80,7 @@ crater/crater_soften.f90\
 crater/crater_subpixel_diffusion.f90\
 crater/crater_make_list.f90\
 crater/crater_mass_conservation.f90\
+crater/crater_critical_slope.f90\
 init/init_domain.f90\
 init/init_dist.f90\
 init/init_surf.f90\