diff --git a/src/Rules.LXgfortran.mk b/src/Rules.LXgfortran.mk
index 4e3af2c943bc5b92690ee01c2820f32fb8630506..708d9ba2f1a8dc488398ea06b0af5a61c790018d 100644
--- a/src/Rules.LXgfortran.mk
+++ b/src/Rules.LXgfortran.mk
@@ -52,6 +52,13 @@ OPT0      = $(OPT_BASE) $(OPT_PERF0) $(OPT_CHECK)
 OPT_NOCB  = $(OPT_BASE) $(OPT_PERF0)
 CFLAGS    += -g -O0
 endif
+ifeq "$(OPTLEVEL)" "OPENACCDEFONLY"
+CPPFLAGS    += -DMNH_OPENACC -D_FAKEOPENACC
+OPT       = $(OPT_BASE) $(OPT_PERF0) $(OPT_CHECK)
+OPT0      = $(OPT_BASE) $(OPT_PERF0) $(OPT_CHECK)
+OPT_NOCB  = $(OPT_BASE) $(OPT_PERF0)
+CFLAGS    += -g -O0
+endif
 #
 ifeq "$(OPTLEVEL)" "OPENACC"
 CPPFLAGS    += -DMNH_OPENACC -fopenacc
diff --git a/src/Rules.LXifort.mk b/src/Rules.LXifort.mk
index e89ea60a34fab24e948a7040ae516eb254a807aa..1c9322b3c129f69ac05fd8bcf8e375fe9c073f27 100644
--- a/src/Rules.LXifort.mk
+++ b/src/Rules.LXifort.mk
@@ -44,6 +44,12 @@ OPT0      = $(OPT_BASE) $(OPT_PERF0) $(OPT_CHECK)
 OPT_NOCB  = $(OPT_BASE) $(OPT_PERF0)
 CFLAGS   += -g
 endif
+ifeq "$(OPTLEVEL)" "OPENACCDEFONLY"
+CPPFLAGS    += -DMNH_OPENACC -D_FAKEOPENACC
+OPT       = $(OPT_BASE) $(OPT_PERF0) $(OPT_CHECK)
+OPT0      = $(OPT_BASE) $(OPT_PERF0) $(OPT_CHECK)
+OPT_NOCB  = $(OPT_BASE) $(OPT_PERF0)
+endif
 ifeq "$(OPTLEVEL)" "O2"
 OPT       = $(OPT_BASE) $(OPT_PERF2)
 OPT0      = $(OPT_BASE) $(OPT_PERF0)