diff --git a/.travis.yml b/.travis.yml
index e07620932..827ea9bf9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,20 +2,17 @@ language: cpp
 
 sudo: false
 
-compiler: clang
-
 addons:
   apt:
     sources:
       - ubuntu-toolchain-r-test
-      - llvm-toolchain-trusty-5.0
     packages:
       - tcsh
       - pkg-config
       - netcdf-bin
       - libnetcdf-dev
       - gfortran
-      - clang-5.0
+      - gcc
       - wget
       #- lftp
 
diff --git a/configuration/scripts/Makefile b/configuration/scripts/Makefile
index acbb2b4f8..47de4b402 100644
--- a/configuration/scripts/Makefile
+++ b/configuration/scripts/Makefile
@@ -105,6 +105,18 @@ db_flags:
 	@echo "* .F.o    := $(FC) -c $(FFLAGS) $(FIXEDFLAGS) $(INCS) $(INCLDIR)"
 	@echo "* .F90.o  := $(FC) -c $(FFLAGS) $(FREEFLAGS) $(INCS) $(INCLDIR)"
 
+#-------------------------------------------------------------------------------
+# build rule for makdep: MACFILE, cmd-line, or env vars must provide
+# the needed macros
+#-------------------------------------------------------------------------------
+
+ifndef $(CFLAGS_HOST)
+  CFLAGS_HOST :=
+endif
+
+$(DEPGEN): $(ICE_CASEDIR)/makdep.c
+	$(SCC) -o $@ $(CFLAGS_HOST) $<
+
 #-------------------------------------------------------------------------------
 # build rules: MACFILE, cmd-line, or env vars must provide the needed macros
 #-------------------------------------------------------------------------------
diff --git a/configuration/scripts/icepack.build b/configuration/scripts/icepack.build
index 0e21185a9..cb92e941c 100755
--- a/configuration/scripts/icepack.build
+++ b/configuration/scripts/icepack.build
@@ -64,7 +64,8 @@ cat ${ICE_OBJDIR}/Filepath
 echo " "
 
 echo "building makdep"
-cc -o makdep ${ICE_CASEDIR}/makdep.c     || exit 2
+${ICE_MACHINE_MAKE} \
+        -f  ${ICE_CASEDIR}/Makefile MACFILE=${ICE_CASEDIR}/Macros.${ICE_MACHCOMP} makdep || exit 2
 
 echo "building icepack > ${ICE_OBJDIR}/${ICE_BLDLOG_FILE}"
 if ( ${ICE_TEST} != ${ICE_SPVAL} ) then
diff --git a/configuration/scripts/machines/Macros.badger_intel b/configuration/scripts/machines/Macros.badger_intel
index 3119351e2..ee16ded00 100644
--- a/configuration/scripts/machines/Macros.badger_intel
+++ b/configuration/scripts/machines/Macros.badger_intel
@@ -18,16 +18,11 @@ else
   FFLAGS     += -O1
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-else
-  FC         := ifort
-endif
-
-MPICC:= mpicc
-
-MPIFC:= mpif90
-LD:= $(MPIFC)
+SCC := icc
+SFC := ifort
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # set in Macros file
 NETCDF_PATH := /usr/projects/climate/SHARED_CLIMATE/software/conejo/netcdf/3.6.3/intel-13.0.1
@@ -50,9 +45,6 @@ else
   SLIBS   := 
 endif
 
-SCC:= icc 
-
-SFC:= ifort 
 
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -qopenmp
diff --git a/configuration/scripts/machines/Macros.cheyenne_intel b/configuration/scripts/machines/Macros.cheyenne_intel
index 622950b9e..804028190 100755
--- a/configuration/scripts/machines/Macros.cheyenne_intel
+++ b/configuration/scripts/machines/Macros.cheyenne_intel
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-else
-  FC         := ifort
-endif
-
-MPICC:= mpicc
-
-MPIFC:= mpif90
-LD:= $(MPIFC)
+SCC := icc
+SFC := ifort
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 NETCDF_PATH := $(NETCDF)
 
@@ -44,10 +39,6 @@ LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff -L$(LIB_PNETCDF) -lpnetcdf -lgptl
 SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(compile_threaded), true) 
    LDFLAGS += -qopenmp 
    CFLAGS += -qopenmp 
diff --git a/configuration/scripts/machines/Macros.conrad_cray b/configuration/scripts/machines/Macros.conrad_cray
index 715f30ed5..cc7e5daa7 100644
--- a/configuration/scripts/machines/Macros.conrad_cray
+++ b/configuration/scripts/machines/Macros.conrad_cray
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= cc
-
-SFC:= ftn
-
 ifeq ($(ICE_THREADED), false) 
    LDFLAGS += -hnoomp
    CFLAGS += -hnoomp
diff --git a/configuration/scripts/machines/Macros.conrad_gnu b/configuration/scripts/machines/Macros.conrad_gnu
index 8f61df5ac..2a62f7de5 100644
--- a/configuration/scripts/machines/Macros.conrad_gnu
+++ b/configuration/scripts/machines/Macros.conrad_gnu
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -fopenmp
    CFLAGS += -fopenmp
diff --git a/configuration/scripts/machines/Macros.conrad_intel b/configuration/scripts/machines/Macros.conrad_intel
index a25b2a2c6..8829771ef 100644
--- a/configuration/scripts/machines/Macros.conrad_intel
+++ b/configuration/scripts/machines/Macros.conrad_intel
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -openmp
    CFLAGS += -openmp
diff --git a/configuration/scripts/machines/Macros.conrad_pgi b/configuration/scripts/machines/Macros.conrad_pgi
index 300823db1..24b958f55 100644
--- a/configuration/scripts/machines/Macros.conrad_pgi
+++ b/configuration/scripts/machines/Macros.conrad_pgi
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O -g
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= cc
-
-SFC:= ftn
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -mp
    CFLAGS += -mp
diff --git a/configuration/scripts/machines/Macros.cori_intel b/configuration/scripts/machines/Macros.cori_intel
index f9ec911c8..e7bfb9c67 100644
--- a/configuration/scripts/machines/Macros.cori_intel
+++ b/configuration/scripts/machines/Macros.cori_intel
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -openmp
    CFLAGS += -openmp
diff --git a/configuration/scripts/machines/Macros.gaffney_gnu b/configuration/scripts/machines/Macros.gaffney_gnu
index 9bf1f9c7e..0047f951d 100644
--- a/configuration/scripts/machines/Macros.gaffney_gnu
+++ b/configuration/scripts/machines/Macros.gaffney_gnu
@@ -1,5 +1,5 @@
 #==============================================================================
-# Macros file for NAVYDSRC gaffney, intel compiler
+# Macros file for NAVYDSRC gaffney, gnu compiler
 #==============================================================================
 
 CPP        := ftn -E
@@ -17,17 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-  LDFLAGS += -lmpi
-else
-  FC         := gfortran
-endif
-
-MPICC:= mpicc
-MPIFC:= mpif90
-#LD:= $(MPIFC)
-LD:= gfortran
+SCC := gcc
+SFC := gfortran
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -45,10 +39,6 @@ INCLDIR += -I$(NETCDF_PATH)/include
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -fopenmp
    CFLAGS += -fopenmp
diff --git a/configuration/scripts/machines/Macros.gaffney_intel b/configuration/scripts/machines/Macros.gaffney_intel
index a47a02534..46f44fcdc 100644
--- a/configuration/scripts/machines/Macros.gaffney_intel
+++ b/configuration/scripts/machines/Macros.gaffney_intel
@@ -18,17 +18,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ifort
-  LDFLAGS += -lmpi
-else
-  FC         := ifort
-endif
-
-MPICC:= icc
-
-MPIFC:= ifort
-LD:= $(MPIFC)
+SCC := icc
+SFC := ifort
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -46,10 +40,6 @@ LIB_NETCDF := $(NETCDF_PATH)/lib
 #LIB_MPI := $(IMPILIBDIR)
 SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -qopenmp
    CFLAGS += -qopenmp
diff --git a/configuration/scripts/machines/Macros.gaffney_pgi b/configuration/scripts/machines/Macros.gaffney_pgi
index 4dc22f319..f811fa9a9 100644
--- a/configuration/scripts/machines/Macros.gaffney_pgi
+++ b/configuration/scripts/machines/Macros.gaffney_pgi
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O -g
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-else
-  FC         := pgf90
-endif
-
-MPICC:= pgcc
-
-MPIFC:= pgf90
-LD:= $(MPIFC)
+SCC := pgcc
+SFC := pgf90
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= pgcc
-
-SFC:= pgf90
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -mp
    CFLAGS += -mp
diff --git a/configuration/scripts/machines/Macros.gordon_cray b/configuration/scripts/machines/Macros.gordon_cray
index a5043f74d..3bea53751 100644
--- a/configuration/scripts/machines/Macros.gordon_cray
+++ b/configuration/scripts/machines/Macros.gordon_cray
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= cc
-
-SFC:= ftn
-
 ifeq ($(ICE_THREADED), false) 
    LDFLAGS += -hnoomp
    CFLAGS += -hnoomp
diff --git a/configuration/scripts/machines/Macros.gordon_gnu b/configuration/scripts/machines/Macros.gordon_gnu
index 81ac94355..1fcf530da 100644
--- a/configuration/scripts/machines/Macros.gordon_gnu
+++ b/configuration/scripts/machines/Macros.gordon_gnu
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -fopenmp
    CFLAGS += -fopenmp
diff --git a/configuration/scripts/machines/Macros.gordon_intel b/configuration/scripts/machines/Macros.gordon_intel
index 5499bd14a..5990f3bdf 100644
--- a/configuration/scripts/machines/Macros.gordon_intel
+++ b/configuration/scripts/machines/Macros.gordon_intel
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -openmp
    CFLAGS += -openmp
diff --git a/configuration/scripts/machines/Macros.gordon_pgi b/configuration/scripts/machines/Macros.gordon_pgi
index bb33626a2..220bd1812 100644
--- a/configuration/scripts/machines/Macros.gordon_pgi
+++ b/configuration/scripts/machines/Macros.gordon_pgi
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O -g
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= cc
-
-SFC:= ftn
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -mp
    CFLAGS += -mp
diff --git a/configuration/scripts/machines/Macros.hobart_intel b/configuration/scripts/machines/Macros.hobart_intel
index 419fb3c03..5a538874e 100755
--- a/configuration/scripts/machines/Macros.hobart_intel
+++ b/configuration/scripts/machines/Macros.hobart_intel
@@ -18,11 +18,9 @@ else
   FFLAGS     += -O2 -debug minimal
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-  LD         := mpif90
-else
-  FC         := ifort
-  LD         := ifort
-endif
+SCC := icc
+SFC := ifort
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
diff --git a/configuration/scripts/machines/Macros.hobart_nag b/configuration/scripts/machines/Macros.hobart_nag
index 30102ac2b..bc54c7655 100755
--- a/configuration/scripts/machines/Macros.hobart_nag
+++ b/configuration/scripts/machines/Macros.hobart_nag
@@ -1,5 +1,5 @@
 #==============================================================================
-# Makefile macros for NCAR cheyenne, intel compiler
+# Makefile macros for NCAR cheyenne, nag compiler
 #==============================================================================
 
 CPP        := /usr/bin/cpp
@@ -19,13 +19,11 @@ else
   FFLAGS   += -O2 -ieee=full
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-  LD         := mpif90
-else
-  FC         := nagfor
-  LD         := nagfor
-endif
+SCC := nagcc
+SFC := nagfor
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 SLIBS   := -L$(COMPILER_PATH)/lib/NAG_Fortran
 
diff --git a/configuration/scripts/machines/Macros.koehr_gnu b/configuration/scripts/machines/Macros.koehr_gnu
index 9c9d8ef49..97950c249 100644
--- a/configuration/scripts/machines/Macros.koehr_gnu
+++ b/configuration/scripts/machines/Macros.koehr_gnu
@@ -17,17 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-  LDFLAGS += -lmpi
-else
-  FC         := gfortran
-endif
-
-MPICC:= mpicc
-MPIFC:= mpif90
-#LD:= $(MPIFC)
-LD:= gfortran
+SCC := gcc
+SFC := gfortran
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -45,10 +39,6 @@ INCLDIR += -I$(NETCDF_PATH)/include
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -fopenmp
    CFLAGS += -fopenmp
diff --git a/configuration/scripts/machines/Macros.koehr_intel b/configuration/scripts/machines/Macros.koehr_intel
index 4839a82df..624056f4a 100644
--- a/configuration/scripts/machines/Macros.koehr_intel
+++ b/configuration/scripts/machines/Macros.koehr_intel
@@ -18,17 +18,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ifort
-  LDFLAGS += -lmpi
-else
-  FC         := ifort
-endif
-
-MPICC:= icc
-
-MPIFC:= ifort
-LD:= $(MPIFC)
+SCC := icc
+SFC := ifort
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -46,10 +40,6 @@ LIB_NETCDF := $(NETCDF_PATH)/lib
 #LIB_MPI := $(IMPILIBDIR)
 SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -qopenmp
    CFLAGS += -qopenmp
diff --git a/configuration/scripts/machines/Macros.koehr_pgi b/configuration/scripts/machines/Macros.koehr_pgi
index a9b3efb3e..f3de98d52 100644
--- a/configuration/scripts/machines/Macros.koehr_pgi
+++ b/configuration/scripts/machines/Macros.koehr_pgi
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O -g
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-else
-  FC         := pgf90
-endif
-
-MPICC:= pgcc
-
-MPIFC:= pgf90
-LD:= $(MPIFC)
+SCC := pgcc
+SFC := pgf90
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= pgcc
-
-SFC:= pgf90
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -mp
    CFLAGS += -mp
diff --git a/configuration/scripts/machines/Macros.loft_gnu b/configuration/scripts/machines/Macros.loft_gnu
index 6ef475c33..0fbf7e005 100644
--- a/configuration/scripts/machines/Macros.loft_gnu
+++ b/configuration/scripts/machines/Macros.loft_gnu
@@ -27,12 +27,11 @@ else
   FFLAGS     += -O2
 endif
 
- 	FC         := gfortran
-
-MPICC:= 
-
-MPIFC:= 
-LD:= $(FC)
+SCC := gcc
+SFC := gfortran
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 ifeq ($(ICE_IOTYPE), netcdf)
   NETCDF_PATH := /usr/projects/climate/SHARED_CLIMATE/software/conejo/netcdf/3.6.3/intel-13.0.1
@@ -45,8 +44,6 @@ else
 endif
 
 LIB_MPI := 
-SCC:= 
-SFC:= 
 
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -openmp
diff --git a/configuration/scripts/machines/Macros.onyx_cray b/configuration/scripts/machines/Macros.onyx_cray
index f0dbad417..b7e011a1f 100644
--- a/configuration/scripts/machines/Macros.onyx_cray
+++ b/configuration/scripts/machines/Macros.onyx_cray
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= cc
-
-SFC:= ftn
-
 ifeq ($(ICE_THREADED), false) 
    LDFLAGS += -hnoomp
    CFLAGS += -hnoomp
diff --git a/configuration/scripts/machines/Macros.onyx_gnu b/configuration/scripts/machines/Macros.onyx_gnu
index 3e092cd71..d22562760 100644
--- a/configuration/scripts/machines/Macros.onyx_gnu
+++ b/configuration/scripts/machines/Macros.onyx_gnu
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -fopenmp
    CFLAGS += -fopenmp
diff --git a/configuration/scripts/machines/Macros.onyx_intel b/configuration/scripts/machines/Macros.onyx_intel
index e2853b280..788ba042e 100644
--- a/configuration/scripts/machines/Macros.onyx_intel
+++ b/configuration/scripts/machines/Macros.onyx_intel
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := ftn
-else
-  FC         := ftn
-endif
-
-MPICC:= cc
-
-MPIFC:= ftn
-LD:= $(MPIFC)
+SCC := cc
+SFC := ftn
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ INCLDIR := $(INCLDIR)
 #LIB_MPI := $(IMPILIBDIR)
 #SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -openmp
    CFLAGS += -openmp
diff --git a/configuration/scripts/machines/Macros.testmachine_intel b/configuration/scripts/machines/Macros.testmachine_intel
index 4e65dbed2..f932b04eb 100755
--- a/configuration/scripts/machines/Macros.testmachine_intel
+++ b/configuration/scripts/machines/Macros.testmachine_intel
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-else
-  FC         := ifort
-endif
-
-MPICC:= mpicc
-
-MPIFC:= mpif90
-LD:= $(MPIFC)
+SCC := icc
+SFC := ifort
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 NETCDF_PATH := $(NETCDF)
 
@@ -43,10 +38,6 @@ LIB_MPI := $(IMPILIBDIR)
 
 SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff -L$(LIB_PNETCDF) -lpnetcdf -lgptl
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(compile_threaded), true) 
    LDFLAGS += -openmp 
    CFLAGS += -openmp 
diff --git a/configuration/scripts/machines/Macros.thunder_intel b/configuration/scripts/machines/Macros.thunder_intel
index 465444275..914ad8f3a 100644
--- a/configuration/scripts/machines/Macros.thunder_intel
+++ b/configuration/scripts/machines/Macros.thunder_intel
@@ -17,16 +17,11 @@ else
   FFLAGS     += -O2
 endif
 
-ifeq ($(ICE_COMMDIR), mpi)
-  FC         := mpif90
-else
-  FC         := ifort
-endif
-
-MPICC:= mpicc
-
-MPIFC:= mpif90
-LD:= $(MPIFC)
+SCC := icc
+SFC := ifort
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 # defined by module
 #NETCDF_PATH := $(NETCDF)
@@ -44,10 +39,6 @@ LIB_PNETCDF := $(PNETCDF_PATH)/lib
 LIB_MPI := $(IMPILIBDIR)
 SLIBS   := -L$(LIB_NETCDF) -lnetcdf -lnetcdff
 
-SCC:= icc 
-
-SFC:= ifort 
-
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -qopenmp
    CFLAGS += -qopenmp
diff --git a/configuration/scripts/machines/Macros.travisCI_gnu b/configuration/scripts/machines/Macros.travisCI_gnu
index baecdf18e..1ef6b44a2 100644
--- a/configuration/scripts/machines/Macros.travisCI_gnu
+++ b/configuration/scripts/machines/Macros.travisCI_gnu
@@ -1,8 +1,8 @@
 #==============================================================================
-# Makefile macros for Travis-CI - gfortran and llvm (clang) compilers
+# Makefile macros for Travis-CI - gnu compiler
 #==============================================================================
 
-CPP        := clang-cpp
+CPP        := /usr/bin/cpp
 CPPDEFS    := -DFORTRANUNDERSCORE ${ICE_CPPDEFS}
 CFLAGS     := -c -O2 -fp-model precise   -xHost
 
@@ -16,12 +16,11 @@ else
     FFLAGS     += -O2
 endif
 
-FC := gfortran
-
-MPICC:= 
-
-MPIFC:= 
-LD:= $(FC)
+SCC := gcc
+SFC := gfortran
+CC := $(SCC)
+FC := $(SFC)
+LD := $(FC)
 
 NETCDF_PATH := $(NETCDF)
 
@@ -36,8 +35,6 @@ else
 endif
 
 LIB_MPI := 
-SCC:= 
-SFC:= 
 
 ifeq ($(ICE_THREADED), true) 
    LDFLAGS += -openmp
diff --git a/doc/source/user_guide/ug_running.rst b/doc/source/user_guide/ug_running.rst
index f05ac2802..574ac58c6 100755
--- a/doc/source/user_guide/ug_running.rst
+++ b/doc/source/user_guide/ug_running.rst
@@ -16,6 +16,8 @@ The icepack scripts are written to allow quick setup of cases and tests.  Once a
 generated, users can manually modify the namelist and other files to custom configure
 the case.  Several settings are available via scripts as well.
 
+.. _overview:
+
 Overview
 ~~~~~~~~
 
@@ -236,7 +238,7 @@ There are other scripts that come with icepack.  These include
 Porting
 -------
 
-To port, an **env.[machine]_[environment]** and **Macros.[machine]_[environment}** file have to be added to the
+To port, an **env.[machine]_[environment]** and **Macros.[machine]_[environment]** file have to be added to the
 **configuration/scripts/machines/** directory and the 
 **configuration/scripts/icepack.batch.csh** file needs to be modified.
 In general, the machine is specified in ``icepack.setup`` with ``--mach``
@@ -264,6 +266,16 @@ directory back to **configuration/scripts/machines/** and update
 the **configuration/scripts/icepack.batch.csh** file, retest, 
 and then add and commit the updated machine files to the repository.
 
+.. _cross_compiling:
+
+Cross-compiling
+~~~~~~~~~~~~~~~~~~~~~~~~
+It can happen that the model must be built on a platform and run on another, for example when the run environment is only available in a batch queue. The program **makdep** (see :ref:`overview`), however, is both compiled and run as part of the build process.
+
+In order to support this, the Makefile uses a variable ``CFLAGS_HOST`` that can hold compiler flags specfic to the build machine for the compilation of makdep. If this feature is needed, add the variable ``CFLAGS_HOST`` to the **Macros.[machine]_[environment]** file. For example : ::
+
+  CFLAGS_HOST = -xHost
+
 .. _account:
 
 Machine Account Settings