[XeTeX] e-TeX \lastnodetype initialization problem

[Hironobu Yamashita]

Hi,

e-TeX primitive \lastnodetype is not working as documented at the start of programs
on WEB2C implementation of pdfTeX, XeTeX and e-pTeX/e-upTeX.
(Only LuaTeX is ok.)
When the current list is empty, \lastnodetype should return -1 instead of 0.

%#!pdftex
\tracingonline1
\showthe\lastnodetype % => 0 ??
\showlists % => empty
\bye


Hironori Kitagawa found the following issue:

etexdir/etex.ch modifies `@<Start a new current page@>` by

@x [45] m.991 l.19353 - e-TeX last_node_type
last_glue:=max_halfword; last_penalty:=0; last_kern:=0;
@y
last_glue:=max_halfword; last_penalty:=0; last_kern:=0;
last_node_type:=-1;
@z

However, tex.ch (WEB2C change file) overrides it so the change has no effect;

@x [16.215] l.4344 - remove mem[] reference from initialize.
prev_graf:=0; shown_mode:=0;
@<Start a new current page@>;
@y
prev_graf:=0; shown_mode:=0;
@/{The following piece of code is a copy of module 991:}
page_contents:=empty; page_tail:=page_head; {|link(page_head):=null;|}@/
last_glue:=max_halfword; last_penalty:=0; last_kern:=0;
page_depth:=0; page_max_depth:=0;
@z

A patch for
* etexdir/tex.ech
* pdftexdir/pdftex.ch
* xetexdir/xetex.ch
is attached.

Best regards,
Hironobu Yamashita

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