GCC 4.6.0 optimizes based on type-based alias analysis. For
example, if b is of type struct buffer * and v of type struct
Lisp_Vector *, then gcc -O2 was incorrectly assuming that &b->size
!= &v->size, and therefore "v->size = 1; b->size = 2; return
v->size;" must therefore return 1. This assumption is incorrect
for Emacs, since it type-puns struct Lisp_Vector * with many other
types. To fix this problem, this patch adds a new type struct
vector_header that documents the constraints on layout of vectors
and pseudovectors, and helps optimizing compilers not get fooled
by Emacs's type punning. It also adds the macros XSETTYPED_PVECTYPE
XSETTYPED_PSEUDOVECTOR, TYPED_PSEUDOVECTORP, for similar reasons.
* lisp.h (XVECTOR_SIZE): New convenience macro. All previous uses of
XVECTOR (foo)->size replaced to use this macro, to avoid the hassle
of writing XVECTOR (foo)->header.size.
(XVECTOR_HEADER_SIZE): New macro, for use in XSETPSEUDOVECTOR.
(XSETTYPED_PVECTYPE): New macro, specifying the name of the size
member.
(XSETPVECTYPE): Rewrite in terms of new macro.
(XSETPVECTYPESIZE): New macro, specifying both type and size.
This is a bit clearer, and further avoids the possibility of
undesirable aliasing.
(XSETTYPED_PSEUDOVECTOR): New macro, specifying the size.
(XSETPSEUDOVECTOR): Rewrite in terms of XSETTYPED_PSEUDOVECTOR
and XVECTOR_HEADER_SIZE.
(XSETSUBR): Rewrite in terms of XSETTYPED_PSEUDOVECTOR and XSIZE,
since Lisp_Subr is a special case (no "next" field).
(ASIZE): Rewrite in terms of XVECTOR_SIZE.
(struct vector_header): New type.
(TYPED_PSEUDOVECTORP): New macro, also specifying the C type of the
object, to help avoid aliasing.
(PSEUDOVECTORP): Rewrite in terms of TYPED_PSEUDOVECTORP.
(SUBRP): Likewise, since Lisp_Subr is a special case.
* lisp.h (struct Lisp_Vector, struct Lisp_Char_Table):
(struct Lisp_Sub_Char_Table, struct Lisp_Bool_Vector):
(struct Lisp_Hash_Table): Combine first two members into a single
struct vector_header member. All uses of "size" and "next" members
changed to be "header.size" and "header.next".
* buffer.h (struct buffer): Likewise.
* font.h (struct font_spec, struct font_entity, struct font): Likewise.
* frame.h (struct frame): Likewise.
* process.h (struct Lisp_Process): Likewise.
* termhooks.h (struct terminal): Likewise.
* window.c (struct save_window_data, struct saved_window): Likewise.
* window.h (struct window): Likewise.
* alloc.c (allocate_buffer, Fmake_bool_vector, allocate_pseudovector):
Use XSETPVECTYPESIZE, not XSETPVECTYPE, to avoid aliasing problems.
* buffer.c (init_buffer_once): Likewise.
* lread.c (defsubr): Use XSETTYPED_PVECTYPE, since Lisp_Subr is a
special case.
* process.c (Fformat_network_address): Use local var for size,
for brevity.
This makes it easier for human readers (and static analyzers)
to see whether these variables are used from other modules.
* alloc.c, buffer.c, bytecode.c, callint.c, casetab.c, category.c:
* ccl.c, character.c, charset.c, cmds.c, coding.c, composite.c:
* data.c, dbusbind.c, dired.c, editfns.c, eval.c, fileio.c, fns.c:
* font.c, frame.c, fringe.c, ftfont.c, image.c, keyboard.c, keymap.c:
* lread.c, macros.c, minibuf.c, print.c, process.c, search.c:
* sound.c, syntax.c, textprop.c, window.c, xdisp.c, xfaces.c, xfns.c:
* xmenu.c, xselect.c:
Declare Q* vars static if they are not used in other modules.
* ccl.h, character.h, charset.h, coding.h, composite.h, font.h:
* frame.h, intervals.h, keyboard.h, lisp.h, process.h, syntax.h:
Remove decls of unexported vars.
* keyboard.h (EVENT_HEAD_UNMODIFIED): Remove now-unused macro.
* src/keyboard.c (input_available_signal): Declare.
(kbd_buffer_nr_stored): New function.
(kbd_buffer_store_event_hold): If kbd_buffer_nr_stored returns
more than KBD_BUFFER_SIZE/2, stop reding input (Bug#6571).
(kbd_buffer_get_event): If input is suspended and kbd_buffer_nr_stored
returns less than KBD_BUFFER_SIZE/4, resume reding input (Bug#6571).
(tty_read_avail_input): If input is on hold, return.
Don't read more that free slots in kbd_buffer (Bug#6571).
* src/process.c (kbd_is_on_hold): New variable.
(hold_keyboard_input, unhold_keyboard_input, kbd_on_hold_p):
New functions.
(wait_reading_process_output): If kbd_on_hold_p returns non-zero,
select on empty input mask.
(init_process): Initialize kbd_is_on_hold to 0.
* src/process.h (hold_keyboard_input, unhold_keyboard_input)
(kbd_on_hold_p): Declare.
* src/dbusbind.c: Include process.h.
(dbus_fd_cb, xd_find_watch_fd, xd_toggle_watch)
(xd_read_message_1): New functions.
(xd_add_watch, xd_remove_watch): Call xd_find_watch_fd. Handle
watch for both read and write.
(Fdbus_init_bus): Also register xd_toggle_watch.
(Fdbus_call_method_asynchronously, Fdbus_method_return_internal)
(Fdbus_method_error_internal, Fdbus_send_signal): Remove call
to dbus_connection_flush.
(xd_read_message): Move most of the code to xd_read_message_1.
Call xd_read_message_1 until status is COMPLETE.
* src/keyboard.c (readable_events, gobble_input): Remove DBUS code.
* src/process.c (gpm_wait_mask, max_gpm_desc): Remove.
(write_mask): New variable.
(max_input_desc): Renamed from max_keyboard_desc.
(fd_callback_info): New variable.
(add_read_fd, delete_read_fd, add_write_fd, delete_write_fd): New
functions.
(Fmake_network_process): FD_SET write_mask.
(deactivate_process): FD_CLR write_mask.
(wait_reading_process_output): Connecting renamed to Writeok.
check_connect removed. check_write is new. Remove references to
gpm. Use Writeok/check_write unconditionally (i.e. no #ifdef
NON_BLOCKING_CONNECT) instead of Connecting.
Loop over file descriptors and call callbacks in fd_callback_info
if file descriptor is ready for I/O.
(add_gpm_wait_descriptor): Just call add_keyboard_wait_descriptor.
(delete_gpm_wait_descriptor): Just call delete_keyboard_wait_descriptor.
(keyboard_bit_set): Use max_input_desc.
(add_keyboard_wait_descriptor, delete_keyboard_wait_descriptor): Remove
#ifdef subprocesses. Use max_input_desc.
(init_process): Initialize write_mask and fd_callback_info.
* src/process.h (add_read_fd, delete_read_fd, add_write_fd)
(delete_write_fd): Declare.
* configure.in: Set up GnuTLS.
* lisp/net/gnutls.el: GnuTLS glue code to set up a connection.
* src/Makefile.in (LIBGNUTLS_LIBS, LIBGNUTLS_CFLAGS, ALL_CFLAGS)
(obj, LIBES): Set up GnuTLS support.
* src/config.in: Set up GnuTLS support.
* src/emacs.c: Set up GnuTLS support and call syms_of_gnutls.
* src/gnutls.c: The source code for GnuTLS support in Emacs.
* src/gnutls.h: The GnuTLS glue for Emacs, macros and enums.
* src/process.c (make_process, Fstart_process)
(read_process_output, send_process): Set up GnuTLS support for
process input/output file descriptors.
* src/process.h: Set up GnuTLS support.
* callproc.c (synch_process_death): Make const.
(Fcall_process): Make signame const.
* emacs.c (main): Pass char[] to putenv instead of literal.
* floatfns.c (matherr): Use a const char* variable for x->name.
* font.c (font_open_by_name): Make name const.
* font.h (font_open_by_name): Make name const.
* gtkutil.c (get_utf8_string): Always return an allocated string.
Parameter is const.
(create_dialog, xg_create_one_menuitem, create_menus)
(xg_item_label_same_p, xg_update_menu_item): Free result from
get_utf8_string.
(xg_separator_p, xg_item_label_same_p): label is const.
* gtkutil.h: Replace widget_value with struct _widget_value.
(enum button_type, struct _widget_value): Remove and use the one from
keyboard.h.
* keyboard.h (_widget_value): Add defined USE_GTK. Replace Boolean
with unsigned char and XtPointer with void *.
* menu.c (Fx_popup_menu): error_name is const.
* menu.h (w32_menu_show, ns_menu_show, xmenu_show): error parameter
is const char **.
* w32menu.c (w32_menu_show):
* nsmenu.m (ns_menu_show): error parameter is const char **.
* process.h (synch_process_death): Is const char*.
* xmenu.c (Fx_popup_dialog): error_name is const char*.
(xmenu_show): error parameter is const char **. pane_string is const
char *.
(button_names): Is const char *.
(xdialog_show): error_name and pane_string is const.
* xrdb.c (get_system_app): Make path const and use char *p for non-const
char.
* xselect.c (Fx_get_atom_name): Use char empty[] instead of literal "".
* xsmfns.c (NOSPLASH_OPT): Change to char[].
(smc_save_yourself_CB): Do xstrdup on all ->type and ->name for
props. Free them at the end.
* xterm.c (emacs_class): New char[] for EMACS_CLASS.
(xim_open_dpy, xim_initialize, xim_close_dpy): Use emacs_class.
(x_term_init): Use char[] display_opt and name_opt instead of
string literal. file is const char*.
* keyboard.c (input_available_signal): Declare.
(kbd_buffer_nr_stored): New function.
(kbd_buffer_store_event_hold): If kbd_buffer_nr_stored returns
more than KBD_BUFFER_SIZE/2, stop reding input (Bug#6571).
(kbd_buffer_get_event): If input is suspended and kbd_buffer_nr_stored
returns less than KBD_BUFFER_SIZE/4, resume reding input (Bug#6571).
(tty_read_avail_input): If input is on hold, return.
Don't read more that free slots in kbd_buffer (Bug#6571).
* process.h (hold_keyboard_input, unhold_keyboard_input)
(kbd_on_hold_p): Declare.
* process.c (kbd_is_on_hold): New variable.
(hold_keyboard_input, unhold_keyboard_input, kbd_on_hold_p): New
functions.
(wait_reading_process_output): If kbd_on_hold_p returns non-zero,
select on empty input mask.
(init_process): Initialize kbd_is_on_hold to 0.
* process.c (QCfilter_multibyte): Remove.
(setup_process_coding_systems): Don't use filter_multibyte.
(Fstart_process, Fmake_network_process): Don't set filter_multibyte.
(read_process_output): Don't adjust multibyteness to filter_multibyte.
(Fset_process_filter_multibyte): Change the coding-system to
approximate the previous behavior.
(Fprocess_filter_multibyte_p): Get the multibyteness straight from the
coding-system.
`raw_status_high', and `raw_status_low' with plain integers, and move
them to the end of the structure.
* alloc.c (allocate_process): Use PSEUDOVECSIZE to initialize the
pseudovector's size field so only the Lisp_Object fields get GC'd.
* process.c (update_status, make_process, Fdelete_process)
(Fprocess_status, list_processes_1, start_process_unwind)
(create_process, Fmake_network_process, server_accept_connection)
(wait_reading_process_output, send_process, Fprocess_running_child_p)
(process_send_signal, proc_encode_coding_system, Fprocess_send_eof)
(sigchld_handler, status_notify): Adjust to new non-Lisp fields for
`pid' and `raw_status'.
(Fprocess_id, Fsignal_process): Same, and additionally use floats when
representing PIDs that are larger than most-positive-fixnum.
