diff --git a/epan/dfilter/dfunctions.c b/epan/dfilter/dfunctions.c
index ba8de42705..5c8b122878 100644
--- a/epan/dfilter/dfunctions.c
+++ b/epan/dfilter/dfunctions.c
@@ -352,12 +352,11 @@ ul_semcheck_compare(dfwork_t *dfw, const char *func_name, ftenum_t lhs_ftype,
     else if (stnode_type_id(arg) == STTYPE_FUNCTION) {
         ftype = check_function(dfw, arg, lhs_ftype);
     }
-    else {
+    else if (stnode_type_id(arg) == STTYPE_FIELD || stnode_type_id(arg) == STTYPE_REFERENCE) {
         ftype = sttype_field_ftenum(arg);
     }
-
-    if (ftype == FT_NONE) {
-        FAIL(dfw, arg, "Argument '%s' (FT_NONE) is not valid for %s()",
+    else {
+        FAIL(dfw, arg, "Argument '%s' is not valid for %s()",
                                 stnode_todisplay(arg), func_name);
     }
 
@@ -375,14 +374,14 @@ ul_semcheck_compare(dfwork_t *dfw, const char *func_name, ftenum_t lhs_ftype,
         else if (stnode_type_id(arg) == STTYPE_FUNCTION) {
             ft_arg = check_function(dfw, arg, ftype);
         }
-        else {
+        else if (stnode_type_id(arg) == STTYPE_FIELD || stnode_type_id(arg) == STTYPE_REFERENCE) {
             ft_arg = sttype_field_ftenum(arg);
         }
-
-        if (ft_arg == FT_NONE) {
-            FAIL(dfw, arg, "Argument '%s' (FT_NONE) is not valid for %s()",
+        else {
+            FAIL(dfw, arg, "Argument '%s' is not valid for %s()",
                                     stnode_todisplay(arg), func_name);
         }
+
         if (ftype == FT_NONE) {
             ftype = ft_arg;
         }
diff --git a/test/suite_dfilter/group_function.py b/test/suite_dfilter/group_function.py
index 460599a6c9..9d80082b3f 100644
--- a/test/suite_dfilter/group_function.py
+++ b/test/suite_dfilter/group_function.py
@@ -66,6 +66,11 @@ class case_dfunction_maxmin(unittest.TestCase):
         dfilter = 'max(udp.srcport, udp.dstport) < 5060'
         checkDFilterCount(dfilter, 1)
 
+    def test_max_4(self, checkDFilterFail):
+        error = 'Argument \'1\' is not valid for max()'
+        dfilter = 'max(1,_ws.ftypes.int8) == 1'
+        checkDFilterFail(dfilter, error)
+
 @fixtures.uses_fixtures
 class case_dfunction_abs(unittest.TestCase):
     trace_file = "dhcp.pcapng"