diff --git libgomp/Makefile.in libgomp/Makefile.in
index 88c8517..33be8c7 100644
--- libgomp/Makefile.in
+++ libgomp/Makefile.in
@@ -380,6 +380,7 @@ mkdir_p = @mkdir_p@
 multi_basedir = @multi_basedir@
 offload_additional_lib_paths = @offload_additional_lib_paths@
 offload_additional_options = @offload_additional_options@
+offload_plugins = @offload_plugins@
 offload_targets = @offload_targets@
 oldincludedir = @oldincludedir@
 pdfdir = @pdfdir@
diff --git libgomp/config.h.in libgomp/config.h.in
index 226ac53..28f7b2d 100644
--- libgomp/config.h.in
+++ libgomp/config.h.in
@@ -98,8 +98,8 @@
    */
 #undef LT_OBJDIR
 
-/* Define to offload targets, separated by commas. */
-#undef OFFLOAD_TARGETS
+/* Define to offload plugins, separated by commas. */
+#undef OFFLOAD_PLUGINS
 
 /* Name of package */
 #undef PACKAGE
diff --git libgomp/configure libgomp/configure
index 8d03eb6..4baab20 100755
--- libgomp/configure
+++ libgomp/configure
@@ -633,6 +633,8 @@ PLUGIN_NVPTX_FALSE
 PLUGIN_NVPTX_TRUE
 offload_additional_lib_paths
 offload_additional_options
+offload_targets
+offload_plugins
 PLUGIN_HSA_LIBS
 PLUGIN_HSA_LDFLAGS
 PLUGIN_HSA_CPPFLAGS
@@ -646,7 +648,6 @@ PLUGIN_NVPTX_CPPFLAGS
 PLUGIN_NVPTX
 CUDA_DRIVER_LIB
 CUDA_DRIVER_INCLUDE
-offload_targets
 libtool_VERSION
 ac_ct_FC
 FCFLAGS
@@ -11145,7 +11146,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11148 "configure"
+#line 11149 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11251,7 +11252,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11254 "configure"
+#line 11255 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -15140,8 +15141,6 @@ esac
 # see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 # <http://www.gnu.org/licenses/>.
 
-offload_targets=
-
 plugin_support=yes
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dlsym in -ldl" >&5
 $as_echo_n "checking for dlsym in -ldl... " >&6; }
@@ -15320,7 +15319,13 @@ PLUGIN_HSA_LIBS=
 
 
 
-# Get offload targets and path to install tree of offloading compiler.
+# Parse offload targets, and figure out libgomp plugin, and configure the
+# corresponding offload compiler.  offload_plugins and offload_targets will be
+# populated in the same order.
+offload_plugins=
+offload_targets=
+
+
 offload_additional_options=
 offload_additional_lib_paths=
 
@@ -15329,13 +15334,13 @@ if test x"$enable_offload_targets" != x; then
   for tgt in `echo $enable_offload_targets | sed -e 's#,# #g'`; do
     tgt_dir=`echo $tgt | grep '=' | sed 's/.*=//'`
     tgt=`echo $tgt | sed 's/=.*//'`
-    tgt_name=
+    tgt_plugin=
     case $tgt in
       *-intelmic-* | *-intelmicemul-*)
-	tgt_name=intelmic
+	tgt_plugin=intelmic
 	;;
       nvptx*)
-        tgt_name=nvptx
+	tgt_plugin=nvptx
 	PLUGIN_NVPTX=$tgt
 	PLUGIN_NVPTX_CPPFLAGS=$CUDA_DRIVER_CPPFLAGS
 	PLUGIN_NVPTX_LDFLAGS=$CUDA_DRIVER_LDFLAGS
@@ -15373,7 +15378,7 @@ rm -f core conftest.err conftest.$ac_objext \
 	    ;;
 	esac
 	;;
-      hsa*)
+      hsa)
 	case "${target}" in
 	  x86_64-*-*)
 	    case " ${CC} ${CFLAGS} " in
@@ -15381,7 +15386,7 @@ rm -f core conftest.err conftest.$ac_objext \
 	        PLUGIN_HSA=0
 		;;
 	      *)
-	        tgt_name=hsa
+		tgt_plugin=hsa
 	        PLUGIN_HSA=$tgt
 	        PLUGIN_HSA_CPPFLAGS=$HSA_RUNTIME_CPPFLAGS
 	        PLUGIN_HSA_LDFLAGS="$HSA_RUNTIME_LDFLAGS $HSA_KMT_LDFLAGS"
@@ -15414,7 +15419,7 @@ rm -f core conftest.err conftest.$ac_objext \
 	        LDFLAGS=$PLUGIN_HSA_save_LDFLAGS
 	        LIBS=$PLUGIN_HSA_save_LIBS
 	        case $PLUGIN_HSA in
-	          hsa*)
+		  hsa)
 	            HSA_PLUGIN=0
 	            as_fn_error "HSA run-time package required for HSA support" "$LINENO" 5
 	            ;;
@@ -15431,16 +15436,19 @@ rm -f core conftest.err conftest.$ac_objext \
 	as_fn_error "unknown offload target specified" "$LINENO" 5
 	;;
     esac
-    if test x"$tgt_name" = x; then
+    if test x"$tgt_plugin" = x; then
       # Don't configure libgomp for this offloading target if we don't build
       # the corresponding plugin.
       continue
-    elif test x"$offload_targets" = x; then
-      offload_targets=$tgt_name
+    elif test x"$offload_plugins" = x; then
+      offload_plugins=$tgt_plugin
+      offload_targets=$tgt
     else
-      offload_targets=$offload_targets,$tgt_name
+      offload_plugins=$offload_plugins,$tgt_plugin
+      offload_targets=$offload_targets,$tgt
     fi
-    if test "$tgt_name" = hsa; then
+    # Configure additional search paths.
+    if test "$tgt_plugin" = hsa; then
       # Offloading compilation is all handled by the target compiler.
       :
     elif test x"$tgt_dir" != x; then
@@ -15454,7 +15462,7 @@ rm -f core conftest.err conftest.$ac_objext \
 fi
 
 cat >>confdefs.h <<_ACEOF
-#define OFFLOAD_TARGETS "$offload_targets"
+#define OFFLOAD_PLUGINS "$offload_plugins"
 _ACEOF
 
  if test $PLUGIN_NVPTX = 1; then
diff --git libgomp/plugin/configfrag.ac libgomp/plugin/configfrag.ac
index 88b4156..de0a6f6 100644
--- libgomp/plugin/configfrag.ac
+++ libgomp/plugin/configfrag.ac
@@ -26,8 +26,6 @@
 # see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 # <http://www.gnu.org/licenses/>.
 
-offload_targets=
-AC_SUBST(offload_targets)
 plugin_support=yes
 AC_CHECK_LIB(dl, dlsym, , [plugin_support=no])
 if test x"$plugin_support" = xyes; then
@@ -142,7 +140,13 @@ AC_SUBST(PLUGIN_HSA_LIBS)
 
 
 
-# Get offload targets and path to install tree of offloading compiler.
+# Parse offload targets, and figure out libgomp plugin, and configure the
+# corresponding offload compiler.  offload_plugins and offload_targets will be
+# populated in the same order.
+offload_plugins=
+offload_targets=
+AC_SUBST(offload_plugins)
+AC_SUBST(offload_targets)
 offload_additional_options=
 offload_additional_lib_paths=
 AC_SUBST(offload_additional_options)
@@ -151,13 +155,13 @@ if test x"$enable_offload_targets" != x; then
   for tgt in `echo $enable_offload_targets | sed -e 's#,# #g'`; do
     tgt_dir=`echo $tgt | grep '=' | sed 's/.*=//'`
     tgt=`echo $tgt | sed 's/=.*//'`
-    tgt_name=
+    tgt_plugin=
     case $tgt in
       *-intelmic-* | *-intelmicemul-*)
-	tgt_name=intelmic
+	tgt_plugin=intelmic
 	;;
       nvptx*)
-        tgt_name=nvptx
+	tgt_plugin=nvptx
 	PLUGIN_NVPTX=$tgt
 	PLUGIN_NVPTX_CPPFLAGS=$CUDA_DRIVER_CPPFLAGS
 	PLUGIN_NVPTX_LDFLAGS=$CUDA_DRIVER_LDFLAGS
@@ -184,7 +188,7 @@ if test x"$enable_offload_targets" != x; then
 	    ;;
 	esac
 	;;
-      hsa*)
+      hsa)
 	case "${target}" in
 	  x86_64-*-*)
 	    case " ${CC} ${CFLAGS} " in
@@ -192,7 +196,7 @@ if test x"$enable_offload_targets" != x; then
 	        PLUGIN_HSA=0
 		;;
 	      *)
-	        tgt_name=hsa
+		tgt_plugin=hsa
 	        PLUGIN_HSA=$tgt
 	        PLUGIN_HSA_CPPFLAGS=$HSA_RUNTIME_CPPFLAGS
 	        PLUGIN_HSA_LDFLAGS="$HSA_RUNTIME_LDFLAGS $HSA_KMT_LDFLAGS"
@@ -214,7 +218,7 @@ if test x"$enable_offload_targets" != x; then
 	        LDFLAGS=$PLUGIN_HSA_save_LDFLAGS
 	        LIBS=$PLUGIN_HSA_save_LIBS
 	        case $PLUGIN_HSA in
-	          hsa*)
+		  hsa)
 	            HSA_PLUGIN=0
 	            AC_MSG_ERROR([HSA run-time package required for HSA support])
 	            ;;
@@ -231,16 +235,19 @@ if test x"$enable_offload_targets" != x; then
 	AC_MSG_ERROR([unknown offload target specified])
 	;;
     esac
-    if test x"$tgt_name" = x; then
+    if test x"$tgt_plugin" = x; then
       # Don't configure libgomp for this offloading target if we don't build
       # the corresponding plugin.
       continue
-    elif test x"$offload_targets" = x; then
-      offload_targets=$tgt_name
+    elif test x"$offload_plugins" = x; then
+      offload_plugins=$tgt_plugin
+      offload_targets=$tgt
     else
-      offload_targets=$offload_targets,$tgt_name
+      offload_plugins=$offload_plugins,$tgt_plugin
+      offload_targets=$offload_targets,$tgt
     fi
-    if test "$tgt_name" = hsa; then
+    # Configure additional search paths.
+    if test "$tgt_plugin" = hsa; then
       # Offloading compilation is all handled by the target compiler.
       :
     elif test x"$tgt_dir" != x; then
@@ -252,8 +259,8 @@ if test x"$enable_offload_targets" != x; then
     fi
   done
 fi
-AC_DEFINE_UNQUOTED(OFFLOAD_TARGETS, "$offload_targets",
-  [Define to offload targets, separated by commas.])
+AC_DEFINE_UNQUOTED(OFFLOAD_PLUGINS, "$offload_plugins",
+  [Define to offload plugins, separated by commas.])
 AM_CONDITIONAL([PLUGIN_NVPTX], [test $PLUGIN_NVPTX = 1])
 AC_DEFINE_UNQUOTED([PLUGIN_NVPTX], [$PLUGIN_NVPTX],
   [Define to 1 if the NVIDIA plugin is built, 0 if not.])
diff --git libgomp/target.c libgomp/target.c
index 48b9ab8..2b7e627 100644
--- libgomp/target.c
+++ libgomp/target.c
@@ -2474,9 +2474,9 @@ gomp_target_fini (void)
     }
 }
 
-/* This function initializes the runtime needed for offloading.
-   It parses the list of offload targets and tries to load the plugins for
-   these targets.  On return, the variables NUM_DEVICES and NUM_DEVICES_OPENMP
+/* This function initializes the runtime for offloading.
+   It parses the list of offload plugins, and tries to load these.
+   On return, the variables NUM_DEVICES and NUM_DEVICES_OPENMP
    will be set, and the array DEVICES initialized, containing descriptors for
    corresponding devices, first the GOMP_OFFLOAD_CAP_OPENMP_400 ones, follows
    by the others.  */
@@ -2493,7 +2493,7 @@ gomp_target_init (void)
   num_devices = 0;
   devices = NULL;
 
-  cur = OFFLOAD_TARGETS;
+  cur = OFFLOAD_PLUGINS;
   if (*cur)
     do
       {
diff --git libgomp/testsuite/Makefile.in libgomp/testsuite/Makefile.in
index 4dbb406..2092dcd 100644
--- libgomp/testsuite/Makefile.in
+++ libgomp/testsuite/Makefile.in
@@ -223,6 +223,7 @@ mkdir_p = @mkdir_p@
 multi_basedir = @multi_basedir@
 offload_additional_lib_paths = @offload_additional_lib_paths@
 offload_additional_options = @offload_additional_options@
+offload_plugins = @offload_plugins@
 offload_targets = @offload_targets@
 oldincludedir = @oldincludedir@
 pdfdir = @pdfdir@
diff --git libgomp/testsuite/lib/libgomp.exp libgomp/testsuite/lib/libgomp.exp
index 1cb4991..4a25421 100644
--- libgomp/testsuite/lib/libgomp.exp
+++ libgomp/testsuite/lib/libgomp.exp
@@ -36,28 +36,6 @@ load_gcc_lib fortran-modules.exp
 # Try to load a test support file, built during libgomp configuration.
 load_file libgomp-test-support.exp
 
-# Populate offload_targets_s (offloading targets separated by a space), and
-# offload_targets_s_openacc (the same, but with OpenACC names; OpenACC spells
-# some of them a little differently).
-set offload_targets_s [split $offload_targets ","]
-set offload_targets_s_openacc {}
-foreach offload_target_openacc $offload_targets_s {
-    # Translate to OpenACC names, or skip if not yet supported.
-    switch $offload_target_openacc {
-	intelmic {
-	    continue
-	}
-	nvptx {
-	    set offload_target_openacc "nvidia"
-	}
-	hsa {
-	    continue
-	}
-    }
-    lappend offload_targets_s_openacc "$offload_target_openacc"
-}
-lappend offload_targets_s_openacc "host"
-
 set dg-do-what-default run
 
 #
@@ -135,9 +113,9 @@ proc libgomp_init { args } {
     set always_ld_library_path ".:${blddir}/.libs"
 
     # Add liboffloadmic build directory in LD_LIBRARY_PATH to support
-    # non-fallback testing for Intel MIC targets
+    # Intel MIC offloading testing.
     global offload_targets
-    if { [string match "*,intelmic,*" ",$offload_targets,"] } {
+    if { [string match "*,*-intelmic*,*" ",$offload_targets,"] } {
 	append always_ld_library_path ":${blddir}/../liboffloadmic/.libs"
 	append always_ld_library_path ":${blddir}/../liboffloadmic/plugin/.libs"
 	# libstdc++ is required by liboffloadmic
@@ -245,8 +223,7 @@ proc libgomp_init { args } {
     # Disable color diagnostics
     lappend ALWAYS_CFLAGS "additional_flags=-fdiagnostics-color=never"
 
-    # Used for support non-fallback offloading.
-    # Help GCC to find target mkoffload.
+    # Help GCC to find offload compilers' mkoffload.
     global offload_additional_options
     if { $offload_additional_options != "" } {
 	lappend ALWAYS_CFLAGS "additional_flags=${offload_additional_options}"
@@ -322,6 +299,28 @@ proc libgomp_option_proc { option } {
     }
 }
 
+# Translate offload target to OpenACC device type.  Return the empty string if
+# not suitable or not yet supported, and "host" for offload target "disable".
+proc offload_target_to_openacc_device_type { offload_target } {
+    switch -glob $offload_target {
+	disable {
+	    return "host"
+	}
+	hsa {
+	    return ""
+	}
+	*-intelmic* {
+	    return ""
+	}
+	nvptx* {
+	    return "nvidia"
+	}
+	default {
+	    error "Unknwon offload target: $offload_target"
+	}
+    }
+}
+
 # Return 1 if offload device is available.
 proc check_effective_target_offload_device { } {
     return [check_runtime_nocache offload_device_available_ {
@@ -373,29 +372,22 @@ proc check_effective_target_openacc_nvidia_accel_present { } {
     } "" ]
 }
 
-# Return 1 if at least one nvidia board is present, and the nvidia device type
-# is selected by default by means of setting the environment variable
-# ACC_DEVICE_TYPE.
+# Return 1 if at least one nvidia board is present, and the OpenACC "nvidia"
+# device type is selected.
 
 proc check_effective_target_openacc_nvidia_accel_selected { } {
     if { ![check_effective_target_openacc_nvidia_accel_present] } {
 	return 0;
     }
-    global offload_target_openacc
-    if { $offload_target_openacc == "nvidia" } {
-        return 1;
-    }
-    return 0;
+    global openacc_device_type
+    return [string match "nvidia" $openacc_device_type]
 }
 
-# Return 1 if the host target is selected for offloaded
+# Return 1 if the OpenACC "host" device type is selected.
 
 proc check_effective_target_openacc_host_selected { } {
-    global offload_target_openacc
-    if { $offload_target_openacc == "host" } {
-        return 1;
-    }
-    return 0;
+    global openacc_device_type
+    return [string match "host" $openacc_device_type]
 }
 
 # Return 1 if the selected OMP device is actually a HSA device
diff --git libgomp/testsuite/libgomp.oacc-c++/c++.exp libgomp/testsuite/libgomp.oacc-c++/c++.exp
index 608b298..befb921 100644
--- libgomp/testsuite/libgomp.oacc-c++/c++.exp
+++ libgomp/testsuite/libgomp.oacc-c++/c++.exp
@@ -70,18 +70,23 @@ if { $lang_test_file_found } {
 	set libstdcxx_includes ""
     }
 
-    # Test OpenACC with available accelerators.
-    foreach offload_target_openacc $offload_targets_s_openacc {
-	set tagopt "-DACC_DEVICE_TYPE_$offload_target_openacc=1"
+    # Test with all offload targets, and with offloading disabled.
+    foreach offload_target [concat [split $offload_targets ","] "disable"] {
+	set openacc_device_type [offload_target_to_openacc_device_type $offload_target]
+	set tagopt "-DACC_DEVICE_TYPE_$openacc_device_type=1"
 
-	switch $offload_target_openacc {
-	    host {
+	switch $openacc_device_type {
+	    "" {
+		untested "$subdir $offload_target offloading"
+		continue
+	    }
+	    "host" {
 		set acc_mem_shared 1
 	    }
-	    nvidia {
+	    "nvidia" {
 		if { ![check_effective_target_openacc_nvidia_accel_present] } {
 		    # Don't bother; execution testing is going to FAIL.
-		    untested "$subdir $offload_target_openacc offloading"
+		    untested "$subdir $offload_target offloading"
 		    continue
 		}
 
@@ -94,12 +99,15 @@ if { $lang_test_file_found } {
 		set acc_mem_shared 0
 	    }
 	    default {
-		set acc_mem_shared 0
+		error "Unknwon OpenACC device type: $openacc_device_type (offload target: $offload_target)"
 	    }
 	}
 	set tagopt "$tagopt -DACC_MEM_SHARED=$acc_mem_shared"
 
-	setenv ACC_DEVICE_TYPE $offload_target_openacc
+	# To avoid overhead, by default only build for the offload target that
+	# we're actually going to test.
+	set tagopt "$tagopt -foffload=$offload_target"
+	setenv ACC_DEVICE_TYPE $openacc_device_type
 
 	# To get better test coverage for device-specific code that is only
 	# ever used in offloading configurations, we'd like more thorough
@@ -108,8 +116,8 @@ if { $lang_test_file_found } {
 	# -O0 and -O2 only, to avoid testing times exploding too much, under
 	# the assumption that between -O0 and -O[something] there is the
 	# biggest difference in the overall structure of the generated code.
-	switch $offload_target_openacc {
-	    host {
+	switch $offload_target {
+	    "disable" {
 		set-torture-options [list \
 					 { -O2 } ]
 	    }
diff --git libgomp/testsuite/libgomp.oacc-c/c.exp libgomp/testsuite/libgomp.oacc-c/c.exp
index b509a10..5355b87 100644
--- libgomp/testsuite/libgomp.oacc-c/c.exp
+++ libgomp/testsuite/libgomp.oacc-c/c.exp
@@ -31,20 +31,25 @@ set ld_library_path $always_ld_library_path
 append ld_library_path [gcc-set-multilib-library-path $GCC_UNDER_TEST]
 set_ld_library_path_env_vars
 
-# Test OpenACC with available accelerators.
+# Test with all offload targets, and with offloading disabled.
 set SAVE_ALWAYS_CFLAGS "$ALWAYS_CFLAGS"
-foreach offload_target_openacc $offload_targets_s_openacc {
+foreach offload_target [concat [split $offload_targets ","] "disable"] {
     set ALWAYS_CFLAGS "$SAVE_ALWAYS_CFLAGS"
-    set tagopt "-DACC_DEVICE_TYPE_$offload_target_openacc=1"
+    set openacc_device_type [offload_target_to_openacc_device_type $offload_target]
+    set tagopt "-DACC_DEVICE_TYPE_$openacc_device_type=1"
 
-    switch $offload_target_openacc {
-	host {
+    switch $openacc_device_type {
+	"" {
+	    untested "$subdir $offload_target offloading"
+	    continue
+	}
+	"host" {
 	    set acc_mem_shared 1
 	}
-	nvidia {
+	"nvidia" {
 	    if { ![check_effective_target_openacc_nvidia_accel_present] } {
 		# Don't bother; execution testing is going to FAIL.
-		untested "$subdir $offload_target_openacc offloading"
+		untested "$subdir $offload_target offloading"
 		continue
 	    }
 
@@ -57,12 +62,15 @@ foreach offload_target_openacc $offload_targets_s_openacc {
 	    set acc_mem_shared 0
 	}
 	default {
-	    set acc_mem_shared 0
+	    error "Unknwon OpenACC device type: $openacc_device_type (offload target: $offload_target)"
 	}
     }
     set tagopt "$tagopt -DACC_MEM_SHARED=$acc_mem_shared"
 
-    setenv ACC_DEVICE_TYPE $offload_target_openacc
+    # To avoid overhead, by default only build for the offload target that
+    # we're actually going to test.
+    set tagopt "$tagopt -foffload=$offload_target"
+    setenv ACC_DEVICE_TYPE $openacc_device_type
 
     # To get better test coverage for device-specific code that is only
     # ever used in offloading configurations, we'd like more thorough
@@ -71,8 +79,8 @@ foreach offload_target_openacc $offload_targets_s_openacc {
     # -O0 and -O2 only, to avoid testing times exploding too much, under
     # the assumption that between -O0 and -O[something] there is the
     # biggest difference in the overall structure of the generated code.
-    switch $offload_target_openacc {
-	host {
+    switch $offload_target {
+	"disable" {
 	    set-torture-options [list \
 				     { -O2 } ]
 	}
diff --git libgomp/testsuite/libgomp.oacc-fortran/fortran.exp libgomp/testsuite/libgomp.oacc-fortran/fortran.exp
index 2d6b647..8507b67 100644
--- libgomp/testsuite/libgomp.oacc-fortran/fortran.exp
+++ libgomp/testsuite/libgomp.oacc-fortran/fortran.exp
@@ -65,30 +65,38 @@ if { $lang_test_file_found } {
     append ld_library_path [gcc-set-multilib-library-path $GCC_UNDER_TEST]
     set_ld_library_path_env_vars
 
-    # Test OpenACC with available accelerators.
-    foreach offload_target_openacc $offload_targets_s_openacc {
-	set tagopt "-DACC_DEVICE_TYPE_$offload_target_openacc=1"
+    # Test with all offload targets, and with offloading disabled.
+    foreach offload_target [concat [split $offload_targets ","] "disable"] {
+	set openacc_device_type [offload_target_to_openacc_device_type $offload_target]
+	set tagopt "-DACC_DEVICE_TYPE_$openacc_device_type=1"
 
-	switch $offload_target_openacc {
+	switch $openacc_device_type {
+	    "" {
+		untested "$subdir $offload_target offloading"
+		continue
+	    }
 	    host {
 		set acc_mem_shared 1
 	    }
 	    nvidia {
 		if { ![check_effective_target_openacc_nvidia_accel_present] } {
 		    # Don't bother; execution testing is going to FAIL.
-		    untested "$subdir $offload_target_openacc offloading"
+		    untested "$subdir $offload_target offloading"
 		    continue
 		}
 
 		set acc_mem_shared 0
 	    }
 	    default {
-		set acc_mem_shared 0
+		error "Unknwon OpenACC device type: $openacc_device_type (offload target: $offload_target)"
 	    }
 	}
 	set tagopt "$tagopt -DACC_MEM_SHARED=$acc_mem_shared"
 
-	setenv ACC_DEVICE_TYPE $offload_target_openacc
+	# To avoid overhead, by default only build for the offload target that
+	# we're actually going to test.
+	set tagopt "$tagopt -foffload=$offload_target"
+	setenv ACC_DEVICE_TYPE $openacc_device_type
 
 	# For Fortran we're doing torture testing, as Fortran has far more tests
 	# with arrays etc. that testing just -O0 or -O2 is insufficient, that is
