diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 79925daa8a0..76585e84cfb 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@
+2017-09-27  Tom Tromey  <tom@tromey.com>
+
+	* symfile.c (add_symbol_file_command)
+	(remove_symbol_file_command, list_overlays_command)
+	(map_overlay_command, unmap_overlay_command)
+	(overlay_auto_command, overlay_manual_command)
+	(overlay_off_command, overlay_load_command): Constify.
+
 2017-09-27  Tom Tromey  <tom@tromey.com>
 
 	* spu-tdep.c (info_spu_event_command, info_spu_signal_command)
diff --git a/gdb/symfile.c b/gdb/symfile.c
index 96b7d6ffb4f..c6e3b902e1e 100644
--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -87,20 +87,10 @@ static void load_command (char *, int);
 static void symbol_file_add_main_1 (const char *args, symfile_add_flags add_flags,
 				    objfile_flags flags);
 
-static void add_symbol_file_command (char *, int);
-
 static const struct sym_fns *find_sym_fns (bfd *);
 
 static void overlay_invalidate_all (void);
 
-static void overlay_auto_command (char *, int);
-
-static void overlay_manual_command (char *, int);
-
-static void overlay_off_command (char *, int);
-
-static void overlay_load_command (char *, int);
-
 static void overlay_command (char *, int);
 
 static void simple_free_overlay_table (void);
@@ -2198,7 +2188,7 @@ print_transfer_performance (struct ui_file *stream,
    value to use.  We are now discontinuing this type of ad hoc syntax.  */
 
 static void
-add_symbol_file_command (char *args, int from_tty)
+add_symbol_file_command (const char *args, int from_tty)
 {
   struct gdbarch *gdbarch = get_current_arch ();
   gdb::unique_xmalloc_ptr<char> filename;
@@ -2333,7 +2323,7 @@ add_symbol_file_command (char *args, int from_tty)
 /* This function removes a symbol file that was added via add-symbol-file.  */
 
 static void
-remove_symbol_file_command (char *args, int from_tty)
+remove_symbol_file_command (const char *args, int from_tty)
 {
   struct objfile *objf = NULL;
   struct program_space *pspace = current_program_space;
@@ -3233,7 +3223,7 @@ find_pc_mapped_section (CORE_ADDR pc)
    Print a list of mapped sections and their PC ranges.  */
 
 static void
-list_overlays_command (char *args, int from_tty)
+list_overlays_command (const char *args, int from_tty)
 {
   int nmapped = 0;
   struct objfile *objfile;
@@ -3275,7 +3265,7 @@ list_overlays_command (char *args, int from_tty)
    Mark the named section as mapped (ie. residing at its VMA address).  */
 
 static void
-map_overlay_command (char *args, int from_tty)
+map_overlay_command (const char *args, int from_tty)
 {
   struct objfile *objfile, *objfile2;
   struct obj_section *sec, *sec2;
@@ -3320,7 +3310,7 @@ map_overlay_command (char *args, int from_tty)
    (ie. resident in its LMA address range, rather than the VMA range).  */
 
 static void
-unmap_overlay_command (char *args, int from_tty)
+unmap_overlay_command (const char *args, int from_tty)
 {
   struct objfile *objfile;
   struct obj_section *sec = NULL;
@@ -3350,7 +3340,7 @@ unmap_overlay_command (char *args, int from_tty)
    Possibly this should be done via a set/show command.  */
 
 static void
-overlay_auto_command (char *args, int from_tty)
+overlay_auto_command (const char *args, int from_tty)
 {
   overlay_debugging = ovly_auto;
   enable_overlay_breakpoints ();
@@ -3363,7 +3353,7 @@ overlay_auto_command (char *args, int from_tty)
    Possibly this should be done via a set/show command.  */
 
 static void
-overlay_manual_command (char *args, int from_tty)
+overlay_manual_command (const char *args, int from_tty)
 {
   overlay_debugging = ovly_on;
   disable_overlay_breakpoints ();
@@ -3376,7 +3366,7 @@ overlay_manual_command (char *args, int from_tty)
    Possibly this should be done via a set/show command.  */
 
 static void
-overlay_off_command (char *args, int from_tty)
+overlay_off_command (const char *args, int from_tty)
 {
   overlay_debugging = ovly_off;
   disable_overlay_breakpoints ();
@@ -3385,7 +3375,7 @@ overlay_off_command (char *args, int from_tty)
 }
 
 static void
-overlay_load_command (char *args, int from_tty)
+overlay_load_command (const char *args, int from_tty)
 {
   struct gdbarch *gdbarch = get_current_arch ();