Replace some xmalloc-family functions with XNEW-family ones

This patch is part of the make-gdb-buildable-in-C++ effort.  The idea is
to change some calls to the xmalloc family of functions to calls to the
equivalents in the XNEW family.  This avoids adding an explicit cast, so
it keeps the code a bit more readable.  Some of them also map relatively
well to a C++ equivalent (XNEW (struct foo) -> new foo), so it will be
possible to do scripted replacements if needed.

I only changed calls that were obviously allocating memory for one or
multiple "objects".  Allocation of variable sizes (such as strings or
buffer handling) will be for later (and won't use XNEW).

  - xmalloc (sizeof (struct foo)) -> XNEW (struct foo)
  - xmalloc (num * sizeof (struct foo)) -> XNEWVEC (struct foo, num)
  - xcalloc (1, sizeof (struct foo)) -> XCNEW (struct foo)
  - xcalloc (num, sizeof (struct foo)) -> XCNEWVEC (struct foo, num)
  - xrealloc (p, num * sizeof (struct foo) -> XRESIZEVEC (struct foo, p, num)
  - obstack_alloc (ob, sizeof (struct foo)) -> XOBNEW (ob, struct foo)
  - obstack_alloc (ob, num * sizeof (struct foo)) -> XOBNEWVEC (ob, struct foo, num)
  - alloca (sizeof (struct foo)) -> XALLOCA (struct foo)
  - alloca (num * sizeof (struct foo)) -> XALLOCAVEC (struct foo, num)

Some instances of xmalloc followed by memset to zero the buffer were
replaced by XCNEW or XCNEWVEC.

I regtested on x86-64, Ubuntu 14.04, but the patch touches many
architecture-specific files.  For those I'll have to rely on the
buildbot or people complaining that I broke their gdb.

gdb/ChangeLog:

	* aarch64-linux-nat.c (aarch64_add_process): Likewise.
	* aarch64-tdep.c (aarch64_gdbarch_init): Likewise.
	* ada-exp.y (write_ambiguous_var): Likewise.
	* ada-lang.c (resolve_subexp): Likewise.
	(user_select_syms): Likewise.
	(assign_aggregate): Likewise.
	(ada_evaluate_subexp): Likewise.
	(cache_symbol): Likewise.
	* addrmap.c (allocate_key): Likewise.
	(addrmap_create_mutable): Likewise.
	* aix-thread.c (sync_threadlists): Likewise.
	* alpha-tdep.c (alpha_push_dummy_call): Likewise.
	(alpha_gdbarch_init): Likewise.
	* amd64-windows-tdep.c (amd64_windows_push_arguments): Likewise.
	* arm-linux-nat.c (arm_linux_add_process): Likewise.
	* arm-linux-tdep.c (arm_linux_displaced_step_copy_insn): Likewise.
	* arm-tdep.c (push_stack_item): Likewise.
	(arm_displaced_step_copy_insn): Likewise.
	(arm_gdbarch_init): Likewise.
	(_initialize_arm_tdep): Likewise.
	* avr-tdep.c (push_stack_item): Likewise.
	* ax-general.c (new_agent_expr): Likewise.
	* block.c (block_initialize_namespace): Likewise.
	* breakpoint.c (alloc_counted_command_line): Likewise.
	(update_dprintf_command_list): Likewise.
	(parse_breakpoint_sals): Likewise.
	(decode_static_tracepoint_spec): Likewise.
	(until_break_command): Likewise.
	(clear_command): Likewise.
	(update_global_location_list): Likewise.
	(get_breakpoint_objfile_data) Likewise.
	* btrace.c (ftrace_new_function): Likewise.
	(btrace_set_insn_history): Likewise.
	(btrace_set_call_history): Likewise.
	* buildsym.c (add_symbol_to_list): Likewise.
	(record_pending_block): Likewise.
	(start_subfile): Likewise.
	(start_buildsym_compunit): Likewise.
	(push_subfile): Likewise.
	(end_symtab_get_static_block): Likewise.
	(buildsym_init): Likewise.
	* cli/cli-cmds.c (source_command): Likewise.
	* cli/cli-decode.c (add_cmd): Likewise.
	* cli/cli-script.c (build_command_line): Likewise.
	(setup_user_args): Likewise.
	(realloc_body_list): Likewise.
	(process_next_line): Likewise.
	(copy_command_lines): Likewise.
	* cli/cli-setshow.c (do_set_command): Likewise.
	* coff-pe-read.c (read_pe_exported_syms): Likewise.
	* coffread.c (coff_locate_sections): Likewise.
	(coff_symtab_read): Likewise.
	(coff_read_struct_type): Likewise.
	* common/cleanups.c (make_my_cleanup2): Likewise.
	* common/common-exceptions.c (throw_it): Likewise.
	* common/filestuff.c (make_cleanup_close): Likewise.
	* common/format.c (parse_format_string): Likewise.
	* common/queue.h (DEFINE_QUEUE_P): Likewise.
	* compile/compile-object-load.c (munmap_list_add): Likewise.
	(compile_object_load): Likewise.
	* compile/compile-object-run.c (compile_object_run): Likewise.
	* compile/compile.c (append_args): Likewise.
	* corefile.c (specify_exec_file_hook): Likewise.
	* cp-support.c (make_symbol_overload_list): Likewise.
	* cris-tdep.c (push_stack_item): Likewise.
	(cris_gdbarch_init): Likewise.
	* ctf.c (ctf_trace_file_writer_new): Likewise.
	* dbxread.c (init_header_files): Likewise.
	(add_new_header_file): Likewise.
	(init_bincl_list): Likewise.
	(dbx_end_psymtab): Likewise.
	(start_psymtab): Likewise.
	(dbx_end_psymtab): Likewise.
	* dcache.c (dcache_init): Likewise.
	* dictionary.c (dict_create_hashed): Likewise.
	(dict_create_hashed_expandable): Likewise.
	(dict_create_linear): Likewise.
	(dict_create_linear_expandable): Likewise.
	* dtrace-probe.c (dtrace_process_dof_probe): Likewise.
	* dummy-frame.c (register_dummy_frame_dtor): Likewise.
	* dwarf2-frame-tailcall.c (cache_new_ref1): Likewise.
	* dwarf2-frame.c (dwarf2_build_frame_info): Likewise.
	(decode_frame_entry_1): Likewise.
	* dwarf2expr.c (new_dwarf_expr_context): Likewise.
	* dwarf2loc.c (dwarf2_compile_expr_to_ax): Likewise.
	* dwarf2read.c (dwarf2_has_info): Likewise.
	(create_signatured_type_table_from_index): Likewise.
	(dwarf2_read_index): Likewise.
	(dw2_get_file_names_reader): Likewise.
	(create_all_type_units): Likewise.
	(read_cutu_die_from_dwo): Likewise.
	(init_tu_and_read_dwo_dies): Likewise.
	(init_cutu_and_read_dies): Likewise.
	(create_all_comp_units): Likewise.
	(queue_comp_unit): Likewise.
	(inherit_abstract_dies): Likewise.
	(read_call_site_scope): Likewise.
	(dwarf2_add_field): Likewise.
	(dwarf2_add_typedef): Likewise.
	(dwarf2_add_member_fn): Likewise.
	(attr_to_dynamic_prop): Likewise.
	(abbrev_table_alloc_abbrev): Likewise.
	(abbrev_table_read_table): Likewise.
	(add_include_dir): Likewise.
	(add_file_name): Likewise.
	(dwarf_decode_line_header): Likewise.
	(dwarf2_const_value_attr): Likewise.
	(dwarf_alloc_block): Likewise.
	(parse_macro_definition): Likewise.
	(set_die_type): Likewise.
	(write_psymtabs_to_index): Likewise.
	(create_cus_from_index): Likewise.
	(dwarf2_create_include_psymtab): Likewise.
	(process_psymtab_comp_unit_reader): Likewise.
	(build_type_psymtab_dependencies): Likewise.
	(read_comp_units_from_section): Likewise.
	(compute_compunit_symtab_includes): Likewise.
	(create_dwo_unit_in_dwp_v1): Likewise.
	(create_dwo_unit_in_dwp_v2): Likewise.
	(read_func_scope): Likewise.
	(process_structure_scope): Likewise.
	(mark_common_block_symbol_computed): Likewise.
	(load_partial_dies): Likewise.
	(dwarf2_symbol_mark_computed): Likewise.
	* elfread.c (elf_symfile_segments): Likewise.
	(elf_read_minimal_symbols): Likewise.
	* environ.c (make_environ): Likewise.
	* eval.c (evaluate_subexp_standard): Likewise.
	* event-loop.c (create_file_handler): Likewise.
	(create_async_signal_handler): Likewise.
	(create_async_event_handler): Likewise.
	(create_timer): Likewise.
	* exec.c (build_section_table): Likewise.
	* fbsd-nat.c (fbsd_remember_child): Likewise.
	* fork-child.c (fork_inferior): Likewise.
	* frv-tdep.c (new_variant): Likewise.
	* gdbarch.sh (gdbarch_alloc): Likewise.
	(append_name): Likewise.
	* gdbtypes.c (rank_function): Likewise.
	(copy_type_recursive): Likewise.
	(add_dyn_prop): Likewise.
	* gnu-nat.c (make_proc): Likewise.
	(make_inf): Likewise.
	(gnu_write_inferior): Likewise.
	* gnu-v3-abi.c (build_gdb_vtable_type): Likewise.
	(build_std_type_info_type): Likewise.
	* guile/scm-param.c (compute_enum_list): Likewise.
	* guile/scm-utils.c (gdbscm_parse_function_args): Likewise.
	* guile/scm-value.c (gdbscm_value_call): Likewise.
	* h8300-tdep.c (h8300_gdbarch_init): Likewise.
	* hppa-tdep.c (hppa_init_objfile_priv_data): Likewise.
	(read_unwind_info): Likewise.
	* ia64-tdep.c (ia64_gdbarch_init): Likewise.
	* infcall.c (dummy_frame_context_saver_setup): Likewise.
	(call_function_by_hand_dummy): Likewise.
	* infcmd.c (step_once): Likewise.
	(finish_forward): Likewise.
	(attach_command): Likewise.
	(notice_new_inferior): Likewise.
	* inferior.c (add_inferior_silent): Likewise.
	* infrun.c (add_displaced_stepping_state): Likewise.
	(save_infcall_control_state): Likewise.
	(save_inferior_ptid): Likewise.
	(_initialize_infrun): Likewise.
	* jit.c (bfd_open_from_target_memory): Likewise.
	(jit_gdbarch_data_init): Likewise.
	* language.c (add_language): Likewise.
	* linespec.c (decode_line_2): Likewise.
	* linux-nat.c (add_to_pid_list): Likewise.
	(add_initial_lwp): Likewise.
	* linux-thread-db.c (add_thread_db_info): Likewise.
	(record_thread): Likewise.
	(info_auto_load_libthread_db): Likewise.
	* m32c-tdep.c (m32c_gdbarch_init): Likewise.
	* m68hc11-tdep.c (m68hc11_gdbarch_init): Likewise.
	* m68k-tdep.c (m68k_gdbarch_init): Likewise.
	* m88k-tdep.c (m88k_analyze_prologue): Likewise.
	* macrocmd.c (macro_define_command): Likewise.
	* macroexp.c (gather_arguments): Likewise.
	* macroscope.c (sal_macro_scope): Likewise.
	* macrotab.c (new_macro_table): Likewise.
	* mdebugread.c (push_parse_stack): Likewise.
	(parse_partial_symbols): Likewise.
	(parse_symbol): Likewise.
	(psymtab_to_symtab_1): Likewise.
	(new_block): Likewise.
	(new_psymtab): Likewise.
	(mdebug_build_psymtabs): Likewise.
	(add_pending): Likewise.
	(elfmdebug_build_psymtabs): Likewise.
	* mep-tdep.c (mep_gdbarch_init): Likewise.
	* mi/mi-main.c (mi_execute_command): Likewise.
	* mi/mi-parse.c (mi_parse_argv): Likewise.
	* minidebug.c (lzma_open): Likewise.
	* minsyms.c (terminate_minimal_symbol_table): Likewise.
	* mips-linux-nat.c (mips_linux_insert_watchpoint): Likewise.
	* mips-tdep.c (mips_gdbarch_init): Likewise.
	* mn10300-tdep.c (mn10300_gdbarch_init): Likewise.
	* msp430-tdep.c (msp430_gdbarch_init): Likewise.
	* mt-tdep.c (mt_registers_info): Likewise.
	* nat/aarch64-linux.c (aarch64_linux_new_thread): Likewise.
	* nat/linux-btrace.c (linux_enable_bts): Likewise.
	(linux_enable_pt): Likewise.
	* nat/linux-osdata.c (linux_xfer_osdata_processes): Likewise.
	(linux_xfer_osdata_processgroups): Likewise.
	* nios2-tdep.c (nios2_gdbarch_init): Likewise.
	* nto-procfs.c (procfs_meminfo): Likewise.
	* objc-lang.c (start_msglist): Likewise.
	(selectors_info): Likewise.
	(classes_info): Likewise.
	(find_methods): Likewise.
	* objfiles.c (allocate_objfile): Likewise.
	(update_section_map): Likewise.
	* osabi.c (gdbarch_register_osabi): Likewise.
	(gdbarch_register_osabi_sniffer): Likewise.
	* parse.c (start_arglist): Likewise.
	* ppc-linux-nat.c (hwdebug_find_thread_points_by_tid): Likewise.
	(hwdebug_insert_point): Likewise.
	* printcmd.c (display_command): Likewise.
	(ui_printf): Likewise.
	* procfs.c (create_procinfo): Likewise.
	(load_syscalls): Likewise.
	(proc_get_LDT_entry): Likewise.
	(proc_update_threads): Likewise.
	* prologue-value.c (make_pv_area): Likewise.
	(pv_area_store): Likewise.
	* psymtab.c (extend_psymbol_list): Likewise.
	(init_psymbol_list): Likewise.
	(allocate_psymtab): Likewise.
	* python/py-inferior.c (add_thread_object): Likewise.
	* python/py-param.c (compute_enum_values): Likewise.
	* python/py-value.c (valpy_call): Likewise.
	* python/py-varobj.c (py_varobj_iter_next): Likewise.
	* python/python.c (ensure_python_env): Likewise.
	* record-btrace.c (record_btrace_start_replaying): Likewise.
	* record-full.c (record_full_reg_alloc): Likewise.
	(record_full_mem_alloc): Likewise.
	(record_full_end_alloc): Likewise.
	(record_full_core_xfer_partial): Likewise.
	* regcache.c (get_thread_arch_aspace_regcache): Likewise.
	* remote-fileio.c (remote_fileio_init_fd_map): Likewise.
	* remote-notif.c (remote_notif_state_allocate): Likewise.
	* remote.c (demand_private_info): Likewise.
	(remote_notif_stop_alloc_reply): Likewise.
	(remote_enable_btrace): Likewise.
	* reverse.c (save_bookmark_command): Likewise.
	* rl78-tdep.c (rl78_gdbarch_init): Likewise.
	* rx-tdep.c (rx_gdbarch_init): Likewise.
	* s390-linux-nat.c (s390_insert_watchpoint): Likewise.
	* ser-go32.c (dos_get_tty_state): Likewise.
	(dos_copy_tty_state): Likewise.
	* ser-mingw.c (ser_windows_open): Likewise.
	(ser_console_wait_handle): Likewise.
	(ser_console_get_tty_state): Likewise.
	(make_pipe_state): Likewise.
	(net_windows_open): Likewise.
	* ser-unix.c (hardwire_get_tty_state): Likewise.
	(hardwire_copy_tty_state): Likewise.
	* solib-aix.c (solib_aix_new_lm_info): Likewise.
	* solib-dsbt.c (dsbt_current_sos): Likewise.
	(dsbt_relocate_main_executable): Likewise.
	* solib-frv.c (frv_current_sos): Likewise.
	(frv_relocate_main_executable): Likewise.
	* solib-spu.c (spu_bfd_fopen): Likewise.
	* solib-svr4.c (lm_info_read): Likewise.
	(svr4_copy_library_list): Likewise.
	(svr4_default_sos): Likewise.
	* source.c (find_source_lines): Likewise.
	(line_info): Likewise.
	(add_substitute_path_rule): Likewise.
	* spu-linux-nat.c (spu_bfd_open): Likewise.
	* spu-tdep.c (info_spu_dma_cmdlist): Likewise.
	* stabsread.c (dbx_lookup_type): Likewise.
	(read_type): Likewise.
	(read_member_functions): Likewise.
	(read_struct_fields): Likewise.
	(read_baseclasses): Likewise.
	(read_args): Likewise.
	(_initialize_stabsread): Likewise.
	* stack.c (func_command): Likewise.
	* stap-probe.c (handle_stap_probe): Likewise.
	* symfile.c (addrs_section_sort): Likewise.
	(addr_info_make_relative): Likewise.
	(load_section_callback): Likewise.
	(add_symbol_file_command): Likewise.
	(init_filename_language_table): Likewise.
	* symtab.c (create_filename_seen_cache): Likewise.
	(sort_search_symbols_remove_dups): Likewise.
	(search_symbols): Likewise.
	* target.c (make_cleanup_restore_target_terminal): Likewise.
	* thread.c (new_thread): Likewise.
	(enable_thread_stack_temporaries): Likewise.
	(make_cleanup_restore_current_thread): Likewise.
	(thread_apply_all_command): Likewise.
	* tic6x-tdep.c (tic6x_gdbarch_init): Likewise.
	* top.c (gdb_readline_wrapper): Likewise.
	* tracefile-tfile.c (tfile_trace_file_writer_new): Likewise.
	* tracepoint.c (trace_find_line_command): Likewise.
	(all_tracepoint_actions_and_cleanup): Likewise.
	(make_cleanup_restore_current_traceframe): Likewise.
	(get_uploaded_tp): Likewise.
	(get_uploaded_tsv): Likewise.
	* tui/tui-data.c (tui_alloc_generic_win_info): Likewise.
	(tui_alloc_win_info): Likewise.
	(tui_alloc_content): Likewise.
	(tui_add_content_elements): Likewise.
	* tui/tui-disasm.c (tui_find_disassembly_address): Likewise.
	(tui_set_disassem_content): Likewise.
	* ui-file.c (ui_file_new): Likewise.
	(stdio_file_new): Likewise.
	(tee_file_new): Likewise.
	* utils.c (make_cleanup_restore_integer): Likewise.
	(add_internal_problem_command): Likewise.
	* v850-tdep.c (v850_gdbarch_init): Likewise.
	* valops.c (find_oload_champ): Likewise.
	* value.c (allocate_value_lazy): Likewise.
	(record_latest_value): Likewise.
	(create_internalvar): Likewise.
	* varobj.c (install_variable): Likewise.
	(new_variable): Likewise.
	(new_root_variable): Likewise.
	(cppush): Likewise.
	(_initialize_varobj): Likewise.
	* windows-nat.c (windows_make_so): Likewise.
	* x86-nat.c (x86_add_process): Likewise.
	* xcoffread.c (arrange_linetable): Likewise.
	(allocate_include_entry): Likewise.
	(process_linenos): Likewise.
	(SYMBOL_DUP): Likewise.
	(xcoff_start_psymtab): Likewise.
	(xcoff_end_psymtab): Likewise.
	* xml-support.c (gdb_xml_parse_attr_ulongest): Likewise.
	* xtensa-tdep.c (xtensa_register_type): Likewise.
	* gdbarch.c: Regenerate.
	* gdbarch.h: Regenerate.

gdb/gdbserver/ChangeLog:

	* ax.c (gdb_parse_agent_expr): Likewise.
	(compile_bytecodes): Likewise.
	* dll.c (loaded_dll): Likewise.
	* event-loop.c (append_callback_event): Likewise.
	(create_file_handler): Likewise.
	(create_file_event): Likewise.
	* hostio.c (handle_open): Likewise.
	* inferiors.c (add_thread): Likewise.
	(add_process): Likewise.
	* linux-aarch64-low.c (aarch64_linux_new_process): Likewise.
	* linux-arm-low.c (arm_new_process): Likewise.
	(arm_new_thread): Likewise.
	* linux-low.c (add_to_pid_list): Likewise.
	(linux_add_process): Likewise.
	(handle_extended_wait): Likewise.
	(add_lwp): Likewise.
	(enqueue_one_deferred_signal): Likewise.
	(enqueue_pending_signal): Likewise.
	(linux_resume_one_lwp_throw): Likewise.
	(linux_resume_one_thread): Likewise.
	(linux_read_memory): Likewise.
	(linux_write_memory): Likewise.
	* linux-mips-low.c (mips_linux_new_process): Likewise.
	(mips_linux_new_thread): Likewise.
	(mips_add_watchpoint): Likewise.
	* linux-x86-low.c (initialize_low_arch): Likewise.
	* lynx-low.c (lynx_add_process): Likewise.
	* mem-break.c (set_raw_breakpoint_at): Likewise.
	(set_breakpoint): Likewise.
	(add_condition_to_breakpoint): Likewise.
	(add_commands_to_breakpoint): Likewise.
	(clone_agent_expr): Likewise.
	(clone_one_breakpoint): Likewise.
	* regcache.c (new_register_cache): Likewise.
	* remote-utils.c (look_up_one_symbol): Likewise.
	* server.c (queue_stop_reply): Likewise.
	(start_inferior): Likewise.
	(queue_stop_reply_callback): Likewise.
	(handle_target_event): Likewise.
	* spu-low.c (fetch_ppc_memory): Likewise.
	(store_ppc_memory): Likewise.
	* target.c (set_target_ops): Likewise.
	* thread-db.c (thread_db_load_search): Likewise.
	(try_thread_db_load_1): Likewise.
	* tracepoint.c (add_tracepoint): Likewise.
	(add_tracepoint_action): Likewise.
	(create_trace_state_variable): Likewise.
	(cmd_qtdpsrc): Likewise.
	(cmd_qtro): Likewise.
	(add_while_stepping_state): Likewise.
	* win32-low.c (child_add_thread): Likewise.
	(get_image_name): Likewise.

2 files changed, 8 insertions, 10 deletions

diff --git a/gdb/tui/tui-data.c b/gdb/tui/tui-data.c
index f610d9c..4623bf0 100644
--- a/gdb/tui/tui-data.c
+++ b/gdb/tui/tui-data.c
@@ -439,9 +439,9 @@ tui_initialize_static_data (void)
 struct tui_gen_win_info *
 tui_alloc_generic_win_info (void)
 {
-  struct tui_gen_win_info *win;
+  struct tui_gen_win_info *win = XNEW (struct tui_gen_win_info);
 
-  if ((win = XNEW (struct tui_gen_win_info)) != NULL)
+  if (win != NULL)
     tui_init_generic_part (win);
 
   return win;
@@ -556,9 +556,8 @@ init_win_info (struct tui_win_info *win_info)
 struct tui_win_info *
 tui_alloc_win_info (enum tui_win_type type)
 {
-  struct tui_win_info *win_info;
+  struct tui_win_info *win_info = XNEW (struct tui_win_info);
 
-  win_info = XNEW (struct tui_win_info);
   if (win_info != NULL)
     {
       win_info->generic.type = type;
@@ -577,7 +576,7 @@ tui_alloc_content (int num_elements, enum tui_win_type type)
   char *element_block_ptr;
   int i;
 
-  content = xmalloc (sizeof (struct tui_win_element *) *num_elements);
+  content = XNEWVEC (struct tui_win_element *, num_elements);
   if (content != NULL)
     {
       /*
@@ -634,7 +633,8 @@ tui_add_content_elements (struct tui_gen_win_info *win_info,
     {
       for (i = index_start; (i < num_elements + index_start); i++)
 	{
-	  if ((element_ptr = XNEW (struct tui_win_element)) != NULL)
+	  element_ptr = XNEW (struct tui_win_element);
+	  if (element_ptr != NULL)
 	    {
 	      win_info->content[i] = (void *) element_ptr;
 	      init_content_element (element_ptr, win_info->type);
diff --git a/gdb/tui/tui-disasm.c b/gdb/tui/tui-disasm.c
index f86c216..70ee907 100644
--- a/gdb/tui/tui-disasm.c
+++ b/gdb/tui/tui-disasm.c
@@ -99,8 +99,7 @@ tui_find_disassembly_address (struct gdbarch *gdbarch, CORE_ADDR pc, int from)
   if (max_lines <= 1)
      return pc;
 
-  asm_lines = (struct tui_asm_line*) alloca (sizeof (struct tui_asm_line)
-                                         * max_lines);
+  asm_lines = XALLOCAVEC (struct tui_asm_line, max_lines);
   memset (asm_lines, 0, sizeof (struct tui_asm_line) * max_lines);
 
   new_low = pc;
@@ -198,8 +197,7 @@ tui_set_disassem_content (struct gdbarch *gdbarch, CORE_ADDR pc)
 							   hilite.  */
 
   /* Get temporary table that will hold all strings (addr & insn).  */
-  asm_lines = (struct tui_asm_line*) alloca (sizeof (struct tui_asm_line)
-                                         * max_lines);
+  asm_lines = XALLOCAVEC (struct tui_asm_line, max_lines);
   memset (asm_lines, 0, sizeof (struct tui_asm_line) * max_lines);
 
   tui_disassemble (gdbarch, asm_lines, pc, max_lines);