diff --git a/editors/awk.c b/editors/awk.c
index 1115085da..c05d5d651 100644
--- a/editors/awk.c
+++ b/editors/awk.c
@@ -139,6 +139,7 @@ typedef struct chain_s {
 /* Function */
 typedef struct func_s {
 	unsigned nargs;
+	smallint defined;
 	struct chain_s body;
 } func;
 
@@ -1662,9 +1663,11 @@ static void parse_program(char *p)
 			debug_printf_parse("%s: TC_FUNCDECL\n", __func__);
 			next_token(TC_FUNCTION);
 			f = newfunc(t_string);
-//FIXME: dup check: functions can't be redefined, this is not ok: awk 'func f(){}; func f(){}'
-			f->body.first = NULL;
-			f->nargs = 0;
+			if (f->defined)
+				syntax_error("Duplicate function");
+			f->defined = 1;
+			//f->body.first = NULL; - already is
+			//f->nargs = 0; - already is
 			/* func arg list: comma sep list of args, and a close paren */
 			for (;;) {
 				if (next_token(TC_VARIABLE | TC_RPAREN) == TC_RPAREN) {
@@ -2912,7 +2915,7 @@ static var *evaluate(node *op, var *res)
 
 			debug_printf_eval("FUNC\n");
 
-			if (op->r.f->nargs == 0 && !op->r.f->body.first)
+			if (!op->r.f->defined)
 				syntax_error(EMSG_UNDEF_FUNC);
 
 			/* The body might be empty, still has to eval the args */
diff --git a/testsuite/awk.tests b/testsuite/awk.tests
index 6e35d33dd..873cc3680 100755
--- a/testsuite/awk.tests
+++ b/testsuite/awk.tests
@@ -44,6 +44,16 @@ testing "awk handles empty function f(arg){}" \
 	"L1\n\nL2\n\n" \
 	"" ""
 
+prg='
+function empty_fun(){}
+END {empty_fun()
+  print "Ok"
+}'
+testing "awk handles empty function f(){}" \
+	"awk '$prg'" \
+	"Ok\n" \
+	"" ""
+
 prg='
 function outer_fun() {
   return 1