diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 7e4fa87c90..b634e52622 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@
+2019-09-20  Tom Tromey  <tom@tromey.com>
+
+	* tui/tui-winsource.h (struct tui_source_window_base)
+	<show_source_content>: Now private.
+	* tui/tui-winsource.c
+	(tui_source_window_base::show_source_content): Don't handle empty
+	content case.
+
 2019-09-20  Tom Tromey  <tom@tromey.com>
 
 	* tui/tui-layout.c (show_source_disasm_command)
diff --git a/gdb/tui/tui-winsource.c b/gdb/tui/tui-winsource.c
index 8b507ed912..683856de81 100644
--- a/gdb/tui/tui-winsource.c
+++ b/gdb/tui/tui-winsource.c
@@ -238,15 +238,10 @@ tui_show_source_line (struct tui_source_window_base *win_info, int lineno)
 void
 tui_source_window_base::show_source_content ()
 {
-  if (!content.empty ())
-    {
-      int lineno;
+  gdb_assert (!content.empty ());
 
-      for (lineno = 1; lineno <= content.size (); lineno++)
-        tui_show_source_line (this, lineno);
-    }
-  else
-    erase_source_content ();
+  for (int lineno = 1; lineno <= content.size (); lineno++)
+    tui_show_source_line (this, lineno);
 
   check_and_display_highlight_if_needed ();
   refresh_window ();
diff --git a/gdb/tui/tui-winsource.h b/gdb/tui/tui-winsource.h
index eca0bde4bb..a66c63597e 100644
--- a/gdb/tui/tui-winsource.h
+++ b/gdb/tui/tui-winsource.h
@@ -76,6 +76,9 @@ struct tui_source_element
 
 struct tui_source_window_base : public tui_win_info
 {
+private:
+  void show_source_content ();
+
 protected:
   explicit tui_source_window_base (enum tui_win_type type);
 
@@ -106,8 +109,6 @@ public:
 
   virtual bool location_matches_p (struct bp_location *loc, int line_no) = 0;
 
-  void show_source_content ();
-
   void update_exec_info ();
 
   /* Update the window to display the given location.  Does nothing if