KNOWNBUG test for function in compilation unit scope

regression/verilog/functioncall/compilation_unit_scope_function.desc

@@ -0,0 +1,9 @@
+KNOWNBUG
+compilation_unit_scope_function.sv
+
+^EXIT=0$
+^SIGNAL=0$
+--
+^warning: ignoring
+--
+The function identifier is not found at the call site.

regression/verilog/functioncall/compilation_unit_scope_function.sv

@@ -0,0 +1,9 @@
+// a function in comilation unit scope
+function integer my_func;
+  my_func = 123;
+endfunction
+
+module main;
+  localparam P = my_func();
+  assert final (P == 123);
+endmodule