(report-emacs-bug "glyphs for chars 128--159")
email -s 'glyphs for chars 128..159' edrx@mat.puc-rio.br






email -s 'glyphs for chars 128..159' bug-gnu-emacs@gnu.org <<'%%%%'
In GNU Emacs 20.3.2 (i386-debian-linux-gnu, X toolkit) of Thu Jan 28
1999 on raven configured using `configure i386-debian-linux-gnu
--prefix=/usr --sharedstatedir=/var/lib --libexecdir=/usr/lib
--localstatedir=/var/lib --infodir=/usr/info --with-pop=yes
--with-x=yes --with-x-toolkit=yes'...

Emacs20 enters an endless loop if it tries to display characters of
the range 128..159 as glyphs (in non-X mode). Here's a way to trigger
the bug: enter emacs; I did it by running

  /usr/bin/emacs20 --no-windows --unibyte --no-init-file glyphbug
  
then execute these two sexprs with C-x C-e:

  (insert (format "%c-A-%c-B-%c" 128 129 130))

  (standard-display-8bit 128 159)

The second one may be replaced by, say,

  (aset standard-display-table 128
	(vector (create-glyph "\e[1;33;41m!\e[m")))

which is on a lower level and still breaks. (This one on a Linux text
console would make char 128 display as a bright yellow "!" on red
background).

Note: Emacs19 (19.34.1) doesn't have any problem in running this code,
and Emacs20 also runs ok with chars outside of the range 128..159,
i.e., in the ranges 0..127 and 160..255:

  (insert (format "%c-%c-%c-%c-%c" 0 27 160 254 255))

  (standard-display-8bit 160 255)
  (aset standard-display-table 0
	(vector (create-glyph "\e[34m*\e[m")))
  (aset standard-display-table 27
	(vector (create-glyph "\e[1;30;42m[\e[m")))
  (aset standard-display-table 160
	(vector (create-glyph "\e[31m6\e[m")))
  (aset standard-display-table 254
	(vector (create-glyph "\e[1;31m\xFE\e[m")))
  (aset standard-display-table 255
	(vector (create-glyph "\e[45m?\e[m")))

More notes: I'm using a standard Intel Debian 2.1 ("Slink") system;
TERM is set to "linux"; Emacs20 need a series of two "C-g"s to abort
(the first one does nothing visible); then it suspends (!!!) and when
restarted it asks "Auto-save? (y or n)" and then "Abort (and dump
core)? (y or n)".

Even more notes: by using gdb to stop emacs20 after it starts to loop
I was convinced that the loop involves at least the functions
write_glyphs and encode_terminal_code (in term.c) and encode_coding
and encode_coding_iso2022 (in coding.c). However I haven't been able
to figure out very well what they're doing, what they should do and
what is looping; please don't flame me too heavily if this is a false
start.

  [],
  Eduardo Ochs
  edrx@inx.com.br
  edrx@mat.puc-rio.br
%%%%