Conference vaxuum::document_ft

670.0. "Nested <MARK>'s -- TeX memory exceeded" by CRAYON::GENT (Party gone out of bounds -- B52&#039;s) Wed Jul 15 1987 17:28

    There is a bug in the handling of <MARK> and <ENDMARK> tags. If you
    nest a pair of <MARK> - <ENDMARK> tags inside another pair, the
    tag translator issues a warning but continues. The Text processor
    churns for an hour or so before issuing the fatal messages:
    
%TEX-E-NOROOM, Exceeded memory capacity:
-TEX-I-MAXHASH, Maximum number of entries in hash table is: 4250
%TEX-I-SHOWCONTEXT, '...annumeral \tempcs \endcsname '
%TEX-I-SHOWCONTEXT, '                                          {#2}\relax \origmark \expan...'
%TEX-I-SHOWCONTEXT, '...or \rvbAmark {\outsidervbMark }'
%TEX-I-SHOWCONTEXT, '                                          \nobreak \or \rvbBmark {\ou...'
%TEX-I-SHOWCONTEXT, '...{\unvbox 255\RVBend 1'
%TEX-I-SHOWCONTEXT, '                                          }\fi \ifdoingrevisionB \set...'
%TEX-I-SHOWCONTEXT, '...maxdepth \RVBpreoutputhook '
%TEX-I-SHOWCONTEXT, '                                          \makeheadline \pagebody \ma...'
%TEX-I-SHOWCONTEXT, '...ax }\fi \fi \else \sdmloutput '
%TEX-I-SHOWCONTEXT, '                                          \fi }'
%TEX-I-SHOWCONTEXT, '                   \end '
%TEX-I-SHOWCONTEXT, '...1:[gent.testfiles.bug]bug2.tex; \bye'
%TEX-I-SHOWCONTEXT, '                                           '
%TEX-I-ONPAGE, on page [1-1185]

    Note the page number.  The following is the source file (hardly 
    1185-lines worth):
    
<revision>
<CHAPTER>(Test of Revision Bars)
<MARK>
<p>
blah, blah, blah...
<note>
etc. etc. etc...
<endnote>
<MARK>
<p>
blah, blah, blah...
<ENDMARK>
<p>
blah, blah, blah...
<ENDMARK>
<p>
blah, blah, blah...

That's why the CHANGEBAR utility keeps an internal count for the
level of nesting, but ends each <mark> level temporarily before
starting the next deeper level. After ending this one, the previous
level is re-started until the nesting counter falls back to zero

Theo

    
    None the less this is a bug. The nested <mark> tag should not
    place any output in the TEX file, and even so, it shouldn't spin
    off into a loop.
    
    The workaround is, obviously, to remove the nested tag.