diff --git a/src/lib/builtins.pl b/src/lib/builtins.pl
index 14e10100..eace0865 100644
--- a/src/lib/builtins.pl
+++ b/src/lib/builtins.pl
@@ -1477,7 +1477,11 @@ open(SourceSink, Mode, Stream, StreamOptions) :-
        (   SourceSink = stream(S0) ->
            '$set_stream_options'(S0, Alias, EOFAction, Reposition, Type),
            Stream = S0
-       ;   '$open'(SourceSink, Mode, Stream, Alias, EOFAction, Reposition, Type)
+       ;   (
+                atom(SourceSink) ->
+                atom_chars(SourceSink, SourceSinkString)
+           ;    SourceSink = SourceSinkString
+           ), '$open'(SourceSinkString, Mode, Stream, Alias, EOFAction, Reposition, Type)
        )
     ).
 
diff --git a/src/loader.pl b/src/loader.pl
index 8872e6f4..531730cc 100644
--- a/src/loader.pl
+++ b/src/loader.pl
@@ -506,7 +506,7 @@ open_file(Path, Stream) :-
     (  atom_concat(_, '.pl', Path) ->
        open(Path, read, Stream)
     ;  catch(open(Path, read, Stream),
-             error(existence_error(source_sink, Path), _),
+             error(existence_error(source_sink, _), _),
              ( atom_concat(Path, '.pl', ExtendedPath),
                open(ExtendedPath, read, Stream) )
             )
diff --git a/src/machine/system_calls.rs b/src/machine/system_calls.rs
index 5df1474f..302e1fc5 100644
--- a/src/machine/system_calls.rs
+++ b/src/machine/system_calls.rs
@@ -3169,31 +3169,10 @@ impl MachineState {
 
                 let options = self.to_stream_options(alias, eof_action, reposition, stream_type);
 
-                let mut stream = match self.store(self.deref(self[temp_v!(1)])) {
-                    Addr::Con(h) if self.heap.atom_at(h) => match &self.heap[h] {
-                        &HeapCellValue::Atom(ref atom, _) => {
-                            self.stream_from_file_spec(atom.clone(), indices, &options)?
-                        }
-                        _ => {
-                            unreachable!()
-                        }
-                    },
-                    Addr::Char(c) => {
-                        let atom = clause_name!(c.to_string(), self.atom_tbl);
-                        self.stream_from_file_spec(atom, indices, &options)?
-                    }
-                    Addr::PStrLocation(h, n) => match &self.heap[h] {
-                        &HeapCellValue::PartialString(_, _has_tail @ false) => {
-                            let mut heap_pstr_iter = self.heap_pstr_iter(Addr::PStrLocation(h, n));
+                let mut iter = self.heap_pstr_iter(self[temp_v!(1)]);
+                let file_spec = clause_name!(iter.to_string(), self.atom_tbl);
 
-                            let file_spec = clause_name!(heap_pstr_iter.to_string(), self.atom_tbl);
-
-                            self.stream_from_file_spec(file_spec, indices, &options)?
-                        }
-                        _ => self.stream_from_file_spec(clause_name!(""), indices, &options)?,
-                    },
-                    _ => self.stream_from_file_spec(clause_name!(""), indices, &options)?,
-                };
+                let mut stream = self.stream_from_file_spec(file_spec, indices, &options)?;
 
                 *stream.options_mut() = options;