Remove some unused variables

This patch removes some unused variables, found with -Wunused.  I have
not removed everything reported by -Wunused, because some expressions
such as

  struct type *arg_type = check_typedef (value_type);

in bfin-tdep.c could have an unexpected but important side-effect.  I
removed others that I considered more low-risk, such as:

  struct gdbarch *gdbarch = get_objfile_arch (objfile);

I tested building with Python 2/Python 3/no Python, with/without expat,
with/without libipt and with/without babeltrace.

gdb/ChangeLog:

	* ada-lang.c (ada_collect_symbol_completion_matches): Remove
	unused variables.
	(ada_is_redundant_range_encoding): Likewise.
	* ada-varobj.c (ada_varobj_get_value_of_array_variable):
	Likewise.
	* alpha-tdep.c (alpha_software_single_step): Likewise.
	* arm-tdep.c (_initialize_arm_tdep): Likewise.
	* auto-load.c (info_auto_load_cmd): Likewise.
	* break-catch-syscall.c (insert_catch_syscall): Likewise.
	(remove_catch_syscall): Likewise.
	* breakpoint.c (condition_completer): Likewise.
	(clear_command): Likewise.
	(update_breakpoint_locations): Likewise.
	* btrace.c (btrace_disable): Likewise.
	(btrace_teardown): Likewise.
	(btrace_maint_update_pt_packets): Likewise.
	(maint_btrace_clear_cmd): Likewise.
	* cli/cli-decode.c (lookup_cmd_1): Likewise.
	(lookup_cmd_composition): Likewise.
	* cli/cli-dump.c (scan_filename): Likewise.
	(restore_command): Likewise.
	* compile/compile-loc2c.c (compute_stack_depth): Likewise.
	* compile/compile-object-load.c (compile_object_load): Likewise.
	* compile/compile-object-run.c (compile_object_run): Likewise.
	* compile/compile.c (compile_to_object): Likewise.
	* completer.c (filename_completer): Likewise.
	(complete_files_symbols): Likewise.
	(complete_expression): Likewise.
	* corelow.c (core_open): Likewise.
	* ctf.c (ctf_start): Likewise.
	(ctf_write_status): Likewise.
	(ctf_write_uploaded_tsv): Likewise.
	(ctf_write_definition_end): Likewise.
	(ctf_open_dir): Likewise.
	(ctf_xfer_partial): Likewise.
	(ctf_trace_find): Likewise.
	* disasm.c (gdb_pretty_print_disassembler::pretty_print_insn):
	Likewise.
	* dwarf2loc.c (allocate_piece_closure): Likewise.
	(indirect_pieced_value): Likewise.
	(dwarf2_evaluate_loc_desc_full): Likewise.
	* dwarf2read.c (dw2_expand_marked_cus): Likewise.
	(dw2_expand_symtabs_matching): Likewise.
	(dw2_map_symbol_filenames): Likewise.
	(read_and_check_comp_unit_head): Likewise.
	(read_cutu_die_from_dwo): Likewise.
	(lookup_dwo_unit): Likewise.
	(read_comp_units_from_section): Likewise.
	(dwarf2_compute_name): Likewise.
	(handle_DW_AT_stmt_list): Likewise.
	(create_cus_hash_table): Likewise.
	(create_dwp_v2_section): Likewise.
	(dwarf2_rnglists_process): Likewise.
	(dwarf2_ranges_process): Likewise.
	(dwarf2_record_block_ranges): Likewise.
	(is_vtable_name): Likewise.
	(read_formatted_entries): Likewise.
	(skip_form_bytes): Likewise.
	* elfread.c (elf_symtab_read): Likewise.
	* exec.c (exec_file_command): Likewise.
	* f-valprint.c (f_val_print): Likewise.
	(info_common_command_for_block): Likewise.
	* guile/guile.c (initialize_scheme_side): Likewise.
	* guile/scm-breakpoint.c (gdbscm_breakpoint_commands): Likewise.
	* guile/scm-cmd.c (cmdscm_completer): Likewise.
	(gdbscm_register_command_x): Likewise.
	* guile/scm-frame.c (gdbscm_frame_read_var): Likewise.
	* guile/scm-param.c (gdbscm_parameter_value): Likewise.
	* guile/scm-ports.c (file_port_magic): Likewise.
	* guile/scm-pretty-print.c (ppscm_search_pp_list): Likewise.
	(ppscm_pretty_print_one_value): Likewise.
	(ppscm_print_children): Likewise.
	* guile/scm-string.c (gdbscm_string_to_argv): Likewise.
	* guile/scm-symtab.c (gdbscm_sal_symtab): Likewise.
	* guile/scm-type.c (gdbscm_type_next_field_x): Likewise.
	* guile/scm-utils.c (gdbscm_parse_function_args): Likewise.
	* i386-tdep.c (i386_register_reggroup_p): Likewise.
	* infcmd.c (run_command_1): Likewise.
	(until_next_fsm_clean_up): Likewise.
	* linespec.c (linespec_complete): Likewise.
	(find_label_symbols): Likewise.
	* m2-valprint.c (m2_val_print): Likewise.
	* memattr.c (require_user_regions): Likewise.
	(lookup_mem_region): Likewise.
	(disable_mem_command): Likewise.
	(mem_delete): Likewise.
	* mep-tdep.c (mep_register_name): Likewise.
	(mep_analyze_prologue): Likewise.
	* mi/mi-cmd-file.c (mi_cmd_file_list_shared_libraries): Likewise.
	* mi/mi-interp.c (mi_on_sync_execution_done): Likewise.
	* mi/mi-main.c (mi_cmd_trace_frame_collected): Likewise.
	* microblaze-linux-tdep.c (microblaze_linux_init_abi): Likewise.
	* minidebug.c (lzma_open): Likewise.
	* minsyms.c (lookup_minimal_symbol): Likewise.
	* mips-linux-tdep.c (mips64_fill_fpregset): Likewise.
	* mips-tdep.c (mips_stub_frame_sniffer): Likewise.
	(mips_o64_return_value): Likewise.
	(mips_single_step_through_delay): Likewise.
	(_initialize_mips_tdep): Likewise.
	* nios2-tdep.c (nios2_push_dummy_call): Likewise.
	(nios2_software_single_step): Likewise.
	* parse.c (find_minsym_type_and_address): Likewise.
	* psymtab.c (psym_relocate): Likewise.
	* python/py-breakpoint.c (bppy_get_commands): Likewise.
	(gdbpy_breakpoint_modified): Likewise.
	* python/py-infevents.c (create_inferior_call_event_object):
	Likewise.
	* python/py-record-btrace.c (btpy_list_item): Likewise.
	* python/py-type.c (typy_str): Likewise.
	* python/py-value.c (valpy_call): Likewise.
	* python/python.c (do_start_initialization): Likewise.
	* record-btrace.c (record_btrace_insn_history_range): Likewise.
	(record_btrace_call_history_range): Likewise.
	(record_btrace_record_method): Likewise.
	(record_btrace_xfer_partial): Likewise.
	(btrace_get_frame_function): Likewise.
	* record-full.c (record_full_open): Likewise.
	* record.c (get_context_size): Likewise.
	* registry.h (DEFINE_REGISTRY): Likewise.
	* remote-fileio.c (remote_fileio_request): Likewise.
	* remote.c (remote_update_thread_list): Likewise.
	(remote_check_symbols): Likewise.
	(remote_commit_resume): Likewise.
	(remote_interrupt): Likewise.
	(remote_insert_breakpoint): Likewise.
	(compare_sections_command): Likewise.
	* rust-exp.y (super_name): Likewise.
	(lex_string): Likewise.
	(convert_ast_to_type): Likewise.
	(convert_ast_to_expression): Likewise.
	* rust-lang.c (rust_print_struct_def): Likewise.
	(rust_print_type): Likewise.
	(rust_evaluate_subexp): Likewise.
	* rx-tdep.c (rx_register_type): Likewise.
	* ser-event.c (serial_event_clear): Likewise.
	* serial.c (serial_open): Likewise.
	* spu-tdep.c (spu_overlay_new_objfile): Likewise.
	* symfile.c (section_is_overlay): Likewise.
	(overlay_unmapped_address): Likewise.
	(overlay_mapped_address): Likewise.
	(simple_overlay_update_1): Likewise.
	(simple_overlay_update): Likewise.
	* symtab.c (symbol_find_demangled_name): Likewise.
	(search_symbols): Likewise.
	* target-descriptions.c (tdesc_predefined_type): Likewise.
	* target.c (target_commit_resume): Likewise.
	* thread.c (print_selected_thread_frame): Likewise.
	* top.c (new_ui_command): Likewise.
	(gdb_readline_no_editing): Likewise.
	* tracefile-tfile.c (tfile_open): Likewise.
	* tracepoint.c (create_tsv_from_upload): Likewise.
	* utils.c (quit): Likewise.
	(defaulted_query): Likewise.
	* valarith.c (value_concat): Likewise.
	* xml-syscall.c (xml_list_syscalls_by_group): Likewise.
	* xml-tdesc.c (target_fetch_description_xml): Likewise.
	* xtensa-tdep.c (xtensa_pseudo_register_read): Likewise.
	(xtensa_pseudo_register_write): Likewise.

gdb/gdbserver/ChangeLog:

	* regcache.c (registers_to_string): Remove unused variable.

Author: Simon Marchi

gdb/ChangeLog

@@ -1,3 +1,164 @@
+2017-12-05  Simon Marchi  <simon.marchi@ericsson.com>
+
+	* ada-lang.c (ada_collect_symbol_completion_matches): Remove
+	unused variables.
+	(ada_is_redundant_range_encoding): Likewise.
+	* ada-varobj.c (ada_varobj_get_value_of_array_variable):
+	Likewise.
+	* alpha-tdep.c (alpha_software_single_step): Likewise.
+	* arm-tdep.c (_initialize_arm_tdep): Likewise.
+	* auto-load.c (info_auto_load_cmd): Likewise.
+	* break-catch-syscall.c (insert_catch_syscall): Likewise.
+	(remove_catch_syscall): Likewise.
+	* breakpoint.c (condition_completer): Likewise.
+	(clear_command): Likewise.
+	(update_breakpoint_locations): Likewise.
+	* btrace.c (btrace_disable): Likewise.
+	(btrace_teardown): Likewise.
+	(btrace_maint_update_pt_packets): Likewise.
+	(maint_btrace_clear_cmd): Likewise.
+	* cli/cli-decode.c (lookup_cmd_1): Likewise.
+	(lookup_cmd_composition): Likewise.
+	* cli/cli-dump.c (scan_filename): Likewise.
+	(restore_command): Likewise.
+	* compile/compile-loc2c.c (compute_stack_depth): Likewise.
+	* compile/compile-object-load.c (compile_object_load): Likewise.
+	* compile/compile-object-run.c (compile_object_run): Likewise.
+	* compile/compile.c (compile_to_object): Likewise.
+	* completer.c (filename_completer): Likewise.
+	(complete_files_symbols): Likewise.
+	(complete_expression): Likewise.
+	* corelow.c (core_open): Likewise.
+	* ctf.c (ctf_start): Likewise.
+	(ctf_write_status): Likewise.
+	(ctf_write_uploaded_tsv): Likewise.
+	(ctf_write_definition_end): Likewise.
+	(ctf_open_dir): Likewise.
+	(ctf_xfer_partial): Likewise.
+	(ctf_trace_find): Likewise.
+	* disasm.c (gdb_pretty_print_disassembler::pretty_print_insn):
+	Likewise.
+	* dwarf2loc.c (allocate_piece_closure): Likewise.
+	(indirect_pieced_value): Likewise.
+	(dwarf2_evaluate_loc_desc_full): Likewise.
+	* dwarf2read.c (dw2_expand_marked_cus): Likewise.
+	(dw2_expand_symtabs_matching): Likewise.
+	(dw2_map_symbol_filenames): Likewise.
+	(read_and_check_comp_unit_head): Likewise.
+	(read_cutu_die_from_dwo): Likewise.
+	(lookup_dwo_unit): Likewise.
+	(read_comp_units_from_section): Likewise.
+	(dwarf2_compute_name): Likewise.
+	(handle_DW_AT_stmt_list): Likewise.
+	(create_cus_hash_table): Likewise.
+	(create_dwp_v2_section): Likewise.
+	(dwarf2_rnglists_process): Likewise.
+	(dwarf2_ranges_process): Likewise.
+	(dwarf2_record_block_ranges): Likewise.
+	(is_vtable_name): Likewise.
+	(read_formatted_entries): Likewise.
+	(skip_form_bytes): Likewise.
+	* elfread.c (elf_symtab_read): Likewise.
+	* exec.c (exec_file_command): Likewise.
+	* f-valprint.c (f_val_print): Likewise.
+	(info_common_command_for_block): Likewise.
+	* guile/guile.c (initialize_scheme_side): Likewise.
+	* guile/scm-breakpoint.c (gdbscm_breakpoint_commands): Likewise.
+	* guile/scm-cmd.c (cmdscm_completer): Likewise.
+	(gdbscm_register_command_x): Likewise.
+	* guile/scm-frame.c (gdbscm_frame_read_var): Likewise.
+	* guile/scm-param.c (gdbscm_parameter_value): Likewise.
+	* guile/scm-ports.c (file_port_magic): Likewise.
+	* guile/scm-pretty-print.c (ppscm_search_pp_list): Likewise.
+	(ppscm_pretty_print_one_value): Likewise.
+	(ppscm_print_children): Likewise.
+	* guile/scm-string.c (gdbscm_string_to_argv): Likewise.
+	* guile/scm-symtab.c (gdbscm_sal_symtab): Likewise.
+	* guile/scm-type.c (gdbscm_type_next_field_x): Likewise.
+	* guile/scm-utils.c (gdbscm_parse_function_args): Likewise.
+	* i386-tdep.c (i386_register_reggroup_p): Likewise.
+	* infcmd.c (run_command_1): Likewise.
+	(until_next_fsm_clean_up): Likewise.
+	* linespec.c (linespec_complete): Likewise.
+	(find_label_symbols): Likewise.
+	* m2-valprint.c (m2_val_print): Likewise.
+	* memattr.c (require_user_regions): Likewise.
+	(lookup_mem_region): Likewise.
+	(disable_mem_command): Likewise.
+	(mem_delete): Likewise.
+	* mep-tdep.c (mep_register_name): Likewise.
+	(mep_analyze_prologue): Likewise.
+	* mi/mi-cmd-file.c (mi_cmd_file_list_shared_libraries): Likewise.
+	* mi/mi-interp.c (mi_on_sync_execution_done): Likewise.
+	* mi/mi-main.c (mi_cmd_trace_frame_collected): Likewise.
+	* microblaze-linux-tdep.c (microblaze_linux_init_abi): Likewise.
+	* minidebug.c (lzma_open): Likewise.
+	* minsyms.c (lookup_minimal_symbol): Likewise.
+	* mips-linux-tdep.c (mips64_fill_fpregset): Likewise.
+	* mips-tdep.c (mips_stub_frame_sniffer): Likewise.
+	(mips_o64_return_value): Likewise.
+	(mips_single_step_through_delay): Likewise.
+	(_initialize_mips_tdep): Likewise.
+	* nios2-tdep.c (nios2_push_dummy_call): Likewise.
+	(nios2_software_single_step): Likewise.
+	* parse.c (find_minsym_type_and_address): Likewise.
+	* psymtab.c (psym_relocate): Likewise.
+	* python/py-breakpoint.c (bppy_get_commands): Likewise.
+	(gdbpy_breakpoint_modified): Likewise.
+	* python/py-infevents.c (create_inferior_call_event_object):
+	Likewise.
+	* python/py-record-btrace.c (btpy_list_item): Likewise.
+	* python/py-type.c (typy_str): Likewise.
+	* python/py-value.c (valpy_call): Likewise.
+	* python/python.c (do_start_initialization): Likewise.
+	* record-btrace.c (record_btrace_insn_history_range): Likewise.
+	(record_btrace_call_history_range): Likewise.
+	(record_btrace_record_method): Likewise.
+	(record_btrace_xfer_partial): Likewise.
+	(btrace_get_frame_function): Likewise.
+	* record-full.c (record_full_open): Likewise.
+	* record.c (get_context_size): Likewise.
+	* registry.h (DEFINE_REGISTRY): Likewise.
+	* remote-fileio.c (remote_fileio_request): Likewise.
+	* remote.c (remote_update_thread_list): Likewise.
+	(remote_check_symbols): Likewise.
+	(remote_commit_resume): Likewise.
+	(remote_interrupt): Likewise.
+	(remote_insert_breakpoint): Likewise.
+	(compare_sections_command): Likewise.
+	* rust-exp.y (super_name): Likewise.
+	(lex_string): Likewise.
+	(convert_ast_to_type): Likewise.
+	(convert_ast_to_expression): Likewise.
+	* rust-lang.c (rust_print_struct_def): Likewise.
+	(rust_print_type): Likewise.
+	(rust_evaluate_subexp): Likewise.
+	* rx-tdep.c (rx_register_type): Likewise.
+	* ser-event.c (serial_event_clear): Likewise.
+	* serial.c (serial_open): Likewise.
+	* spu-tdep.c (spu_overlay_new_objfile): Likewise.
+	* symfile.c (section_is_overlay): Likewise.
+	(overlay_unmapped_address): Likewise.
+	(overlay_mapped_address): Likewise.
+	(simple_overlay_update_1): Likewise.
+	(simple_overlay_update): Likewise.
+	* symtab.c (symbol_find_demangled_name): Likewise.
+	(search_symbols): Likewise.
+	* target-descriptions.c (tdesc_predefined_type): Likewise.
+	* target.c (target_commit_resume): Likewise.
+	* thread.c (print_selected_thread_frame): Likewise.
+	* top.c (new_ui_command): Likewise.
+	(gdb_readline_no_editing): Likewise.
+	* tracefile-tfile.c (tfile_open): Likewise.
+	* tracepoint.c (create_tsv_from_upload): Likewise.
+	* utils.c (quit): Likewise.
+	(defaulted_query): Likewise.
+	* valarith.c (value_concat): Likewise.
+	* xml-syscall.c (xml_list_syscalls_by_group): Likewise.
+	* xml-tdesc.c (target_fetch_description_xml): Likewise.
+	* xtensa-tdep.c (xtensa_pseudo_register_read): Likewise.
+	(xtensa_pseudo_register_write): Likewise.
+
 2017-12-04  Tom Tromey  <tom@tromey.com>
 
 	* NEWS: Mention Rust trait object inspection.

gdb/ada-lang.c

@@ -6475,7 +6475,6 @@ ada_collect_symbol_completion_matches (completion_tracker &tracker,
   struct minimal_symbol *msymbol;
   struct objfile *objfile;
   const struct block *b, *surrounding_static_block = 0;
-  int i;
   struct block_iterator iter;
   struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
 
@@ -8652,7 +8651,6 @@ static int
 ada_is_redundant_range_encoding (struct type *range_type,
 				 struct type *encoding_type)
 {
-  struct type *fixed_range_type;
   const char *bounds_str;
   int n;
   LONGEST lo, hi;

gdb/ada-varobj.c

@@ -825,7 +825,6 @@ ada_varobj_get_value_of_array_variable (struct value *value,
 					struct type *type,
 					struct value_print_options *opts)
 {
-  char *result;
   const int numchild = ada_varobj_get_array_number_of_children (value, type);
 
   /* If we have a string, provide its contents in the "value" field.

gdb/alpha-tdep.c

@@ -1723,10 +1723,7 @@ alpha_next_pc (struct regcache *regcache, CORE_ADDR pc)
 std::vector<CORE_ADDR>
 alpha_software_single_step (struct regcache *regcache)
 {
-  struct gdbarch *gdbarch = regcache->arch ();
-  CORE_ADDR pc;
-
-  pc = alpha_next_pc (regcache, regcache_read_pc (regcache));
+  CORE_ADDR pc = alpha_next_pc (regcache, regcache_read_pc (regcache));
 
   return {pc};
 }

gdb/arm-tdep.c

@@ -9546,8 +9546,6 @@ void
 _initialize_arm_tdep (void)
 {
   long length;
-  const char *setname;
-  const char *setdesc;
   int i, j;
   char regdesc[1024], *rdptr = regdesc;
   size_t rest = sizeof (regdesc);

gdb/auto-load.c

@@ -1521,7 +1521,6 @@ static void
 info_auto_load_cmd (const char *args, int from_tty)
 {
   struct cmd_list_element *list;
-  struct cleanup *infolist_chain;
   struct ui_out *uiout = current_uiout;
 
   ui_out_emit_tuple tuple_emitter (uiout, "infolist");

gdb/break-catch-syscall.c

@@ -104,8 +104,6 @@ insert_catch_syscall (struct bp_location *bl)
     {
       for (int iter : c->syscalls_to_be_caught)
 	{
-          int elem;
-
 	  if (iter >= inf_data->syscalls_counts.size ())
 	    inf_data->syscalls_counts.resize (iter + 1);
 	  ++inf_data->syscalls_counts[iter];
@@ -137,7 +135,6 @@ remove_catch_syscall (struct bp_location *bl, enum remove_bp_reason reason)
     {
       for (int iter : c->syscalls_to_be_caught)
 	{
-          int elem;
 	  if (iter >= inf_data->syscalls_counts.size ())
 	    /* Shouldn't happen.  */
 	    continue;

gdb/breakpoint.c

@@ -921,7 +921,6 @@ condition_completer (struct cmd_list_element *cmd,
     {
       int len;
       struct breakpoint *b;
-      VEC (char_ptr) *result = NULL;
 
       if (text[0] == '$')
 	{
@@ -11479,7 +11478,6 @@ clear_command (const char *arg, int from_tty)
 {
   struct breakpoint *b;
   int default_match;
-  int i;
 
   std::vector<symtab_and_line> decoded_sals;
   symtab_and_line last_sal;
@@ -13664,7 +13662,6 @@ update_breakpoint_locations (struct breakpoint *b,
 			     gdb::array_view<const symtab_and_line> sals,
 			     gdb::array_view<const symtab_and_line> sals_end)
 {
-  int i;
   struct bp_location *existing_locations;
 
   if (!sals_end.empty () && (sals.size () != 1 || sals_end.size () != 1))

gdb/btrace.c

@@ -1636,7 +1636,6 @@ void
 btrace_disable (struct thread_info *tp)
 {
   struct btrace_thread_info *btp = &tp->btrace;
-  int errcode = 0;
 
   if (btp->target == NULL)
     return;
@@ -1656,7 +1655,6 @@ void
 btrace_teardown (struct thread_info *tp)
 {
   struct btrace_thread_info *btp = &tp->btrace;
-  int errcode = 0;
 
   if (btp->target == NULL)
     return;
@@ -3021,7 +3019,6 @@ btrace_maint_decode_pt (struct btrace_maint_info *maint,
 static void
 btrace_maint_update_pt_packets (struct btrace_thread_info *btinfo)
 {
-  volatile struct gdb_exception except;
   struct pt_packet_decoder *decoder;
   struct btrace_data_pt *pt;
   struct pt_config config;
@@ -3358,7 +3355,6 @@ maint_btrace_clear_packet_history_cmd (const char *args, int from_tty)
 static void
 maint_btrace_clear_cmd (const char *args, int from_tty)
 {
-  struct btrace_thread_info *btinfo;
   struct thread_info *tp;
 
   if (args != NULL && *args != 0)

gdb/cli/cli-decode.c

@@ -1386,7 +1386,7 @@ lookup_cmd_1 (const char **text, struct cmd_list_element *clist,
 	      struct cmd_list_element **result_list, int ignore_help_classes)
 {
   char *command;
-  int len, tmp, nfound;
+  int len, nfound;
   struct cmd_list_element *found, *c;
   const char *line = *text;
 
@@ -1715,7 +1715,7 @@ lookup_cmd_composition (const char *text,
                       struct cmd_list_element **cmd)
 {
   char *command;
-  int len, tmp, nfound;
+  int len, nfound;
   struct cmd_list_element *cur_list;
   struct cmd_list_element *prev_cmd;