=================================================================== RCS file: /cvs/mandoc/TODO,v retrieving revision 1.26 retrieving revision 1.219 diff -u -p -r1.26 -r1.219 --- mandoc/TODO 2010/07/16 22:10:04 1.26 +++ mandoc/TODO 2016/07/19 21:31:55 1.219 @@ -1,103 +1,667 @@ ************************************************************************ +* Official mandoc TODO. +* $Id: TODO,v 1.219 2016/07/19 21:31:55 schwarze Exp $ +************************************************************************ + +Many issues are annotated for difficulty as follows: + + - loc = locality of the issue + * single file issue, affects file only, or very few + ** single module issue, affects several files of one module + *** cross-module issue, significantly impacts multiple modules + and may require substantial changes to internal interfaces + - exist = difficulty of the existing code in this area + * affected code is straightforward and easy to read and change + ** affected code is somewhat complex, but once you understand + the design, not particularly difficult to understand + *** affected code uses a special, exceptionally tricky design + - algo = difficulty of the new algorithm to be written + * the required logic and code is straightforward + ** the required logic is somewhat complex and needs a careful design + *** the required logic is exceptionally tricky, + maybe an approach to solve that is not even known yet + - size = the amount of code to be written or changed + * a small number of lines (at most 100, usually much less) + ** a considerable amount of code (several dozen to a few hundred) + *** a large amount of code (many hundreds, maybe thousands) + - imp = importance of the issue + * mostly for completeness + ** would be nice to have + *** issue causes considerable inconvenience + +Obviously, as the issues have not been solved yet, these annotations +are mere guesses, and some may be wrong. + +************************************************************************ +* crashes +************************************************************************ + +- The abort() in bufcat(), html.c, can be triggered via buffmt_includes() + by running -Thtml -Oincludes on a file containing a long .In argument. + Fixing this will probably require reworking the whole bufcat() concept. + loc ** exist * algo * size ** imp ** + +************************************************************************ * missing features ************************************************************************ -- explicit blocks with missing end macro should be implicitely closed - at the end of the enclosing block, e.g. .Bl It (El) Sh - reminded by stsp@ in net/pptp pptp.8 Fri, 23 Apr 2010 20:32:39 +0200 +--- missing roff features ---------------------------------------------- -- fix bad block nesting involving multiple identical explicit blocks - see the OpenBSD mdoc_macro.c 1.47 commit message +- .ad (adjust margins) + .ad l -- adjust left margin only (flush left) + .ad r -- adjust right margin only (flush right) + .ad c -- center text on line + .ad b -- adjust both margins (alias: .ad n) + .na -- temporarily disable adjustment without changing the mode + .ad -- re-enable adjustment without changing the mode + Adjustment mode is ignored while in no-fill mode (.nf). + loc *** exist *** algo ** size ** imp ** (parser reorg would help) +- .fc (field control) + found by naddy@ in xloadimage(1) + loc ** exist *** algo * size * imp * + +- .nr third argument (auto-increment step size, requires \n+) + found by bentley@ in sbcl(1) Mon, 9 Dec 2013 18:36:57 -0700 + loc * exist * algo * size * imp ** + +- .ns (no-space mode) occurs in xine-config(1) + when implementing this, also let .TH set it + reported by brad@ Sat, 15 Jan 2011 15:45:23 -0500 + loc *** exist *** algo *** size ** imp * + +- .ta (tab settings) + #1 most important issue naddy@ Mon, 16 Feb 2015 20:59:17 +0100 + ircbug(1) gnats(1) reported by brad@ Sat, 15 Jan 2011 15:50:51 -0500 + also Tcl_NewStringObj(3) via wiz@ Wed, 5 Mar 2014 22:27:43 +0100 + also posix2time(3) Carsten Kunze Mon, 1 Dec 2014 13:03:10 +0100 + loc ** exist *** algo ** size ** imp *** + +- .ti (temporary indent) + found by naddy@ in xloadimage(1) [devel/libvstr] vstr(3) + found by bentley@ in nmh(1) Mon, 23 Apr 2012 13:38:28 -0600 + loc ** exist ** algo ** size * imp ** (parser reorg helps a lot) + +- .while and .shift + found by jca@ in ratpoison(1) Sun, 30 Jun 2013 12:01:09 +0200 + loc * exist ** algo ** size ** imp ** + +- \h horizontal move + #2 most important issue naddy@ Mon, 16 Feb 2015 20:59:17 +0100 + found in cclive(1) nasm(1) bogofilter(1) asciidoc/DocBook output + bentley@ on discuss@ Sat, 21 Sep 2013 22:29:34 -0600 + naddy@ Thu, 4 Dec 2014 16:26:41 +0100 + loc ** exist ** algo ** size * imp *** (parser reorg helps a lot) + +- \n+ and \n- numerical register increment and decrement + found by bentley@ in sbcl(1) Mon, 9 Dec 2013 18:36:57 -0700 + loc * exist * algo * size * imp ** + +- \n(.$ macro argument count number register; ocserv(8) by autogen + found by sthen@ Thu, 19 Feb 2015 22:03:01 +0000 + loc * exist ** algo * size * imp ** + +- \w'' improve width measurements + would not be very useful without an expression parser, see below + needed for Tcl_NewStringObj(3) via wiz@ Wed, 5 Mar 2014 22:27:43 +0100 + loc ** exist *** algo *** size * imp *** + +- \\ in high-level macro arguments + Currently, \\ is expanded in two situations: + 1) macro and string definition (roff.c setstrn()) + 2) macro argument parsing (mandoc.c mandoc_getarg()) + For user defined macros, the second happens in time because of ROFF_REPARSE. + But for standard high-level macros, it only happens after entering the + high level parsers, which is too late because the code doesn't get + back to roff.c roff_res() from that point. Because this requires + distinguishing requests, user-defined macros and standard macros + on the roff_res() level, it is hard to solve without the parser reorg. + Found by naddy@ in devel/cutils cobfusc(1) Mon, 16 Feb 2015 19:10:52 +0100 + loc *** exist *** algo *** size ** imp * + +- using undefined strings or macros defines them to be empty + wl@ Mon, 14 Nov 2011 14:37:01 +0000 + loc * exist * algo * size * imp * + +--- missing mdoc features ---------------------------------------------- + - .Bl -column .Xo support is missing ultimate goal: restore .Xr and .Dv to lib/libc/compat-43/sigvec.3 lib/libc/gen/signal.3 lib/libc/sys/sigaction.2 + loc * exist *** algo *** size * imp ** -- implement \\ - in plain text, identical to \e - as a macro argument, identical to \ i.e. escaping the next character - We do not have macro definitions yet; if we implement them, - \\ must behave in a macro def like in a macro argument, - and when using the macro, it must expand yet again. +- edge case: decide how to deal with blk_full bad nesting, e.g. + .Sh .Nm .Bk .Nm .Ek .Sh found by jmc@ in ssh-keygen(1) + from jmc@ Wed, 14 Jul 2010 18:10:32 +0100 + loc * exist *** algo *** size ** imp ** -- implement \s (physical font size) - \sN - set to N - \s+N - increment by N, 1 <= N <= 8 - \s-N - decrement by N, 1 <= N <= 8 - \s0 - restore previous size - \s(nn \s+-(nn \s'+-nn' \s+-'nn' \s[+-nn] \s+-[nn] - disambiguate - registers: .s .ps .sr .psr - used by e.g. cu(1), tip(1) +- .Bd -centered implies -filled, not -unfilled, which is not + easy to implement; it requires code similar to .ce, which + we don't have either. + Besides, groff has bug causing text right *before* .Bd -centered + to be centered as well. + loc *** exist *** algo ** size ** imp ** (parser reorg would help) -- look at bsd.lv tbl(1) - from kristaps@ Fri, 11 Sep 2009 17:10:53 +0200 - also look at the mail from Thomas Klausner wiz at NetBSD - on Wed, 2 Jun 2010 11:01:29 +0200 +- .Bd -filled should not be the same as .Bd -ragged, but align both + the left and right margin. In groff, it is implemented in terms + of .ad b, which we don't have either. Found in cksum(1). + loc *** exist *** algo ** size ** imp ** (parser reorg would help) -- look at pages generated from reStructeredText, e.g. devel/mercurial hg(1) - These are a weird mixture of man(7) and custom autogenerated low-level - roff stuff. Figure out to what extent we can cope. - noted by stsp@ Sat, 24 Apr 2010 09:17:55 +0200 - reminded by nicm@ Mon, 3 May 2010 09:52:41 +0100 - - implement blank `Bl -column', such as .Bl -column .It foo Ta bar .El + loc * exist *** algo *** size * imp * - explicitly disallow nested `Bl -column', which would clobber internal flags defined for struct mdoc_macro + loc * exist * algo * size * imp ** -- set a meaningful default if no `Bl' list type is assigned +- In .Bl -column .It, the end of the line probably has to be regarded + as an implicit .Ta, if there could be one, see the following mildly + ugly code from login.conf(5): + .Bl -column minpasswordlen program xetcxmotd + .It path Ta path Ta value of Dv _PATH_DEFPATH + .br + Default search path. + reported by Michal Mazurek + via jmc@ Thu, 7 Apr 2011 16:00:53 +0059 + loc * exist *** algo ** size * imp ** -- have a blank `It' head for `Bl -tag' not puke +- inside `.Bl -column' phrases, punctuation is handled like normal + text, e.g. `.Bl -column .It Fl x . Ta ...' should give "-x -." -- ignore horrendous m[] font colouring - reported by J.C. Roberts +- inside `.Bl -column' phrases, TERMP_IGNDELIM handling by `Pf' + is not safe, e.g. `.Bl -column .It Pf a b .' gives "ab." + but should give "ab ." +- check whether it is correct that `D1' uses INDENT+1; + does it need its own constant? + loc * exist ** algo ** size * imp ** + - prohibit `Nm' from having non-text HEAD children (e.g., NetBSD mDNSShared/dns-sd.1) (mdoc_html.c and mdoc_term.c `Nm' handlers can be slightly simplified) - + +- support translated section names + e.g. x11/scrotwm scrotwm_es.1:21:2: error: NAME section must be first + that one uses NOMBRE because it is spanish... + deraadt tends to think that section-dependent macro behaviour + is a bad idea in the first place, so this may be irrelevant + loc ** exist ** algo ** size * imp ** + +- When there is free text in the SYNOPSIS and that free text contains + the .Nm macro, groff somehow understands to treat the .Nm as an in-line + macro, while mandoc treats it as a block macro and breaks the line. + No idea how the logic for distinguishing in-line and block instances + should be, needs investigation. + uqs@ Thu, 2 Jun 2011 11:03:51 +0200 + uqs@ Thu, 2 Jun 2011 11:33:35 +0200 + loc * exist ** algo *** size * imp ** + +--- missing man features ----------------------------------------------- + +- -T[x]html doesn't stipulate non-collapsing spaces in literal mode + +--- missing tbl features ----------------------------------------------- + +- horizontal lines in the layout still consume data cells + and can be mixed with actual data on the same table line + synaptics(4) found by tedu@ Mon, 17 Aug 2015 21:17:42 -0400 + loc ** exist ** algo ** size ** imp *** + +- the "w" layout option is ignored + synaptics(4) found by tedu@ Mon, 17 Aug 2015 21:17:42 -0400 + loc * exist * algo * size * imp ** + +- the "s" layout column specifier is used for placement of data + into columns, but ignored during column width calculations + synaptics(4) found by tedu@ Mon, 17 Aug 2015 21:17:42 -0400 + loc * exist ** algo *** size * imp ** + +- support mdoc(7) and man(7) macros inside tbl(7) code; + probably requires the parser reorg and letting tbl(7) + use roff_node such that macro sets can mix; + informed by bapt@ that FreeBSD needs this. + loc *** exist ** algo *** size ** imp *** + +- look at the POSIX manuals in the books/man-pages-posix port, + they use some unsupported tbl(7) features. + loc * exist ** algo ** size ** imp *** + +- use Unicode U+2500 to U+256C for table borders + in tbl(7) -Tutf-8 output + suggested by bentley@ Tue, 14 Oct 2014 04:10:55 -0600 + loc * exist ** algo * size * imp ** + +--- missing eqn features ----------------------------------------------- + +- In a matrix, break the output line after each matrix line. + Found in the discussion at CDBUG 2015. + Suggested by Avi Weinstock. + loc * exist * algo * size * imp ** + +- The "size" keyword is parsed, but ignored by the formatter. + loc * exist * algo * size * imp * + +- The spacing characters `~', `^', and tab are currently ignored, + see User's Guide (Second Edition) page 2 section 4. + loc * exist * algo ** size * imp ** + +- Mark and lineup are parsed and ignored, + see User's Guide (Second Edition) page 5 section 15. + loc ** exist ** algo ** size ** imp ** + +--- missing misc features ---------------------------------------------- + +- italic correction (\/) in PostScript mode + Werner LEMBERG on groff at gnu dot org Sun, 10 Nov 2013 12:47:46 + loc ** exist ** algo * size * imp * + +- change the default PAGER to more -Es and use the pager + even for apropos title line output; req by bapt@ + loc * exist * algo * size * imp *** + +- makewhatis(8) for preformatted pages: + parse the section number from the header line + and compare to the section number from the directory name + loc * exist * algo * size * imp ** + +- Does makewhatis(8) detect missing NAME sections, missing names, + and missing descriptions in all the file formats? + loc * exist * algo * size * imp *** + +- clean up escape sequence handling, creating three classes: + (1) fully implemented, or parsed and ignored without loss of content + (2) unimplemented, potentially causing loss of content + or serious mangling of formatting (e.g. \n) -> ERROR + see textproc/mgdiff(1) for nice examples + (3) undefined, just output the character -> perhaps WARNING + loc *** exist ** algo ** size ** imp *** (parser reorg helps) + +- kettenis wants base roff, ms, and me Fri, 1 Jan 2010 22:13:15 +0100 (CET) + loc ** exist ** algo ** size *** imp * + +- Vsevolod Stakhov (FreeBSD) needs either a markdown output formatter + for mandoc -mdoc or a markdown to mdoc converter because they + have to maintain manuals needed both in markdown and mdoc format. + Look at the libsoldout (markdown -> whatever) + loc * exist * algo * size ** imp ** + +--- compatibility checks ----------------------------------------------- + +- is .Bk implemented correctly in modern groff? + sobrado@ Tue, 19 Apr 2011 22:12:55 +0200 + +- compare output to Heirloom roff, Solaris roff, and + http://repo.or.cz/w/neatroff.git http://litcave.rudi.ir/ + +- look at AT&T DWB http://www2.research.att.com/sw/download + Carsten Kunze has patches + Mon, 4 Aug 2014 17:01:28 +0200 + +- look at pages generated from reStructeredText, e.g. devel/mercurial hg(1) + These are a weird mixture of man(7) and custom autogenerated low-level + roff stuff. Figure out to what extent we can cope. + For details, see http://docutils.sourceforge.net/rst.html + noted by stsp@ Sat, 24 Apr 2010 09:17:55 +0200 + reminded by nicm@ Mon, 3 May 2010 09:52:41 +0100 + +- look at pages generated from ronn(1) github.com/rtomayko/ronn + (based on markdown) + +- look at pages generated from Texinfo source by yat2m, e.g. security/gnupg + First impression is not that bad. + +- look at pages generated by pandoc; see + https://github.com/jgm/pandoc/blob/master/src/Text/Pandoc/Writers/Man.hs + porting planned by kili@ Thu, 19 Jun 2014 19:46:28 +0200 + +- check compatibility with Plan9: + http://swtch.com/usr/local/plan9/tmac/tmac.an + http://swtch.com/plan9port/man/man7/man.html + "Anthony J. Bentley" 28 Dec 2010 21:58:40 -0700 + +- check compatibility with COHERENT troff: + http://www.nesssoftware.com/home/mwc/source.php + +- check compatibility with the man(7) formatter + https://raw.githubusercontent.com/rofl0r/hardcore-utils/master/man.c + +- check compatibility with + http://ikiwiki.info/plugins/contrib/mandoc/ + https://github.com/schmonz/ikiwiki/compare/mandoc + Amitai Schlair Mon, 19 May 2014 14:05:53 -0400 + ************************************************************************ * formatting issues: ugly output ************************************************************************ -- outside list context, text following .Sm off - seems to follow without a blank (TERM_NOBLANK reset late?) e.g. - .Sm off - .Xo - .Op Ar bind_address No / - .Ar port - .Xc - .Sm on - or by enclosing - reported by jmc Tue, 13 Apr 2010 08:48:14 +0100 +- revisit empty in-line macros + look at the difference between "Em x Em ." and "Sq x Em ." + Carsten Kunze Fri, 12 Dec 2014 00:15:41 +0100 + loc *** exist *** algo *** size * imp ** +- a column list with blank `Ta' cells triggers a spurious + start-with-whitespace printing of a newline + +- In .Bl -column, .It a"bc" + shows the quotes in groff, but not in mandoc + loc * exist *** algo ** size * imp ** + +- In .Bl -column, + .It Em AuthenticationKey Length + ought to render "Key Length" with emphasis, too, + see OpenBSD iked.conf(5). + reported again Nicolas Joly via wiz@ Wed, 12 Oct 2011 00:20:00 +0200 + loc * exist *** algo *** size ** imp *** + - empty phrases in .Bl column produce too few blanks try e.g. .Bl -column It Ta Ta reported by millert Fri, 02 Apr 2010 16:13:46 -0400 + loc * exist *** algo *** size * imp ** +- .%T can have trailing punctuation. Currently, it puts the trailing + punctuation into a trailing MDOC_TEXT element inside its own scope. + That element should rather be outside its scope, such that the + punctuation does not get underlines. This is not trivial to + implement because .%T then needs some features of in_line_eoln() - + slurp all arguments into one single text element - and one feature + of in_line() - put trailing punctuation out of scope. + Found in mount_nfs(8) and exports(5), search for "Appendix". + loc ** exist ** algo *** size * imp ** + +- Trailing punctuation after .%T triggers EOS spacing, at least + outside .Rs (eek!). Simply setting ARGSFL_DELIM for .%T is not + the right solution, it sends mandoc into an endless loop. + reported by Nicolas Joly Sat, 17 Nov 2012 11:49:54 +0100 + loc * exist ** algo ** size * imp ** + +- global variables in the SYNOPSIS of section 3 pages + .Vt vs .Vt/.Va vs .Ft/.Va vs .Ft/.Fa ... + from kristaps@ Tue, 08 Jun 2010 11:13:32 +0200 + +- in enclosures, mandoc sometimes fancies a bogus end of sentence + reminded by jmc@ Thu, 23 Sep 2010 18:13:39 +0059 + loc * exist ** algo *** size * imp *** + +- a line starting with "\fB something" counts as starting with whitespace + and triggers a line break; found in audio/normalize-mp3(1) + loc ** exist * algo ** size * imp ** + +- formatting /usr/local/man/man1/latex2man.1 with groff and mandoc + reveals lots of bugs both in groff and mandoc... + reported by bentley@ Wed, 22 May 2013 23:49:30 -0600 + +--- PDF issues --------------------------------------------------------- + +- PDF output doesn't use a monospaced font for .Bd -literal + Example: "mandoc -Tpdf afterboot.8 > output.pdf && pdfviewer output.pdf". + Search the text "Routing tables". + Also check what PostScript mode does when fixing this. + reported by juanfra@ Wed, 04 Jun 2014 21:44:58 +0200 + instructions from juanfra@ Wed, 11 Jun 2014 02:21:01 +0200 + add a new <> block to the PDF files with /BaseFont /Courier + and change the /Name from /F0 to the new font (/F5 (?)). + loc * exist ** algo ** size * imp ** + +--- HTML issues -------------------------------------------------------- + +-
formatting is ugly + hints are easy to find on the web, e.g. + http://stackoverflow.com/questions/1713048/ + see also matthew@ Fri, 18 Jul 2014 19:25:12 -0700 + loc * exist * algo ** size * imp *** + +- In -man -Thtml, .nf does not preserve indentation. + It should either convert blanks to   + or use 
 rather than 
 (like .Bd -literal does).
+  Reported by afresh1@  12 Apr 2016 14:35:45 -0700
+
+- .Bf at the beginning of a paragraph inserts a bogus 1ex horizontal
+  space, see for example random(3).  Introduced in
+  http://mdocml.bsd.lv/cgi-bin/cvsweb/mdoc_html.c.diff?r1=1.91&r2=1.92
+  reported by deraadt@ Mon, 28 Sep 2015 20:14:13 -0600 (MDT)
+  loc **  exist **  algo **  size *  imp *
+
+- jsg on icb, Nov 3, 2014:
+  try to guess Xr in man(7) for hyperlinking
+
+- The tables used to render the three-part page headers actually force
+  the width of the  to the max-width given for .
+  Not yet sure how to fix that...
+  Observed by an Anonymous Coward on undeadly.org:
+  http://undeadly.org/cgi?action=article&sid=20140925064244&pid=1
+  loc *  exist *  algo **  size *  imp ***
+
+- consider whether  can be used for Ar Dv Er Ev Fa Va.
+  from bentley@  Wed, 13 Aug 2014 09:17:55 -0600
+
+- generate  tags in HTML
+  idea from florian@  Tue, 7 Apr 2015 00:26:28 +0000
+  may be possible to implement with .Lk img://something.png alt_text
+
+- check https://github.com/trentm/mdocml
+
 ************************************************************************
-* formatting issues: gratuitious differences
+* formatting issues: gratuitous differences
 ************************************************************************
 
-- none reported right now (yet schwarze@ knows of some)
+- .Fn reopens a new scope after punctuation in mandoc,
+  but closes its scope for good in groff.
+  Do we want to change mandoc or groff?
+  Steffen Nurpmeso  Sat, 08 Nov 2014 13:34:59 +0100
+  loc *  exist **  algo **  size *  imp **
 
+- In .Bl -enum -width 0n, groff continues one the same line after
+  the number, mandoc breaks the line.
+  mail to kristaps@  Mon, 20 Jul 2009 02:21:39 +0200
+  loc *  exist **  algo **  size *  imp **
+
+- .Pp between two .It in .Bl -column should produce one,
+  not two blank lines, see e.g. login.conf(5).
+  reported by jmc@  Sun, 17 Apr 2011 14:04:58 +0059
+  reported again by sthen@  Wed, 18 Jan 2012 02:09:39 +0000 (UTC)
+  loc *  exist ***  algo **  size *  imp **
+
+- If the *first* line after .It is .Pp, break the line right after
+  the tag, do not pad with space characters before breaking.
+  See the description of the a, c, and i commands in sed(1).
+  loc *  exist **  algo **  size *  imp **
+
+- If the first line after .It is .D1, do not assert a blank line
+  in between, see for example tmux(1).
+  reported by nicm@  13 Jan 2011 00:18:57 +0000
+  loc *  exist **  algo **  size *  imp **
+
+- Trailing punctuation after .It should trigger EOS spacing.
+  reported by Nicolas Joly  Sat, 17 Nov 2012 11:49:54 +0100
+  Probably, this should be fixed somewhere in termp_it_pre(), not sure.
+  loc *  exist **  algo **  size *  imp **
+
+- .Nx 1.0a
+  should be "NetBSD 1.0A", not "NetBSD 1.0a",
+  see OpenBSD ccdconfig(8).
+  loc *  exist *  algo *  size *  imp **
+
+- In .Bl -tag, if a tag exceeds the right margin and must be continued
+  on the next line, it must be indented by -width, not width+1;
+  see "rule block|pass" in OpenBSD ifconfig(8).
+  loc *  exist ***  algo **  size *  imp **
+
+- When the -width string contains macros, the macros must be rendered
+  before measuring the width, for example
+    .Bl -tag -width ".Dv message"
+  in magic(5), located in src/usr.bin/file, is the same
+  as -width 7n, not -width 11n.
+  The same applies to .Bl -column column widths;
+  reported again by Nicolas Joly Thu, 1 Mar 2012 13:41:26 +0100 via wiz@ 5 Mar
+  reported again by Franco Fichtner Fri, 27 Sep 2013 21:02:28 +0200
+  loc ***  exist ***  algo ***  size **  imp ***
+  An easy partial fix would be to just skip the first word if it starts
+  with a dot, including any following white space, when measuring.
+  loc *  exist *  algo *  size *  imp ***
+
+- The \& zero-width character counts as output.
+  That is, when it is alone on a line between two .Pp,
+  we want three blank lines, not two as in mandoc.
+  loc **  exist **  algo **  size *  imp **
+
+- Header lines of excessive length:
+  Port OpenBSD man_term.c rev. 1.25 to mdoc_term.c
+  and document it in mdoc(7) and man(7) COMPATIBILITY
+  found while talking to Chris Bennett
+  loc *  exist *  algo *  size *  imp *
+
+- Sequences of multiple man(7) paragraphs (.PP, .IP) interspersed
+  with .ps and .nf/.fi produce execessive blank lines, see libJudy
+  and graphics/dcmtk.  The parser reorg may help with this.
+
+- trailing whitespace must be ignored even when followed by a font escape,
+  see for example
+    makes
+    \fBdig \fR
+    operate in batch mode
+  in dig(1).
+  loc **  exist **  algo **  size *  imp **
+
 ************************************************************************
+* portability
+************************************************************************
+
+- systems having UTF-8 but not en_US.UTF-8
+  call locale(1) from ./configure, select a UTF-8-locale,
+  and use that for test-wchar.c and term_ascii.c
+  to Markus Waldeck  Sat, 18 Jul 2015 01:55:37 +0200
+  loc *  exist *  algo *  size *  imp *
+
+************************************************************************
+* warning issues
+************************************************************************
+
+- provide a way in mandoc(1) to warn about broken .Xr links;
+  probably cannot be on by default in -Tlint because it needs
+  to access the manpath and mandoc.db(3) after parsing.
+  asked for by jmc@ Fri, 4 Dec 2015 22:39:40 +0000
+
+- Report errors in -O suboption parsing.
+  loc *  exist *  algo *  size *  imp **
+
+- warn when .Sh or .Ss contain other macros
+  Steffen Nurpmeso, savannah.gnu.org/bugs/index.php?45034
+  loc *  exist *  algo *  size *  imp **
+
+- check that MANDOCERR_BADTAB is thrown in the right cases,
+  i.e. when finding a literal tab character in fill mode,
+  and possibly change the wording of the warning message
+  to refer to fill mode, not literal mode
+  See the mail from Werner LEMBERG on the groff list,
+  Fri, 14 Feb 2014 18:54:42 +0100 (CET)
+  loc *  exist **  algo **  size *  imp **
+
+- warn about attempts to call non-callable macros
+  Steffen Nurpmeso  Tue, 11 Nov 2014 22:55:16 +0100
+  Note that formatting is inconsistent in groff.
+  .Fn Po prints "Po()", .Ar Sh prints "file ..." and no "Sh".
+  Relatively hard because the relevant code is scattered
+  all over mdoc_macro.c and all subtly different.
+  loc **  exist **  algo **  size **  imp **
+
+- warn about "new sentence, new line"
+  loc **  exist **  algo ***  size *  imp **
+
+- mandoc_special does not really check the escape sequence,
+  but just the overall format
+  loc **  exist **  algo ***  size **  imp **
+
+- integrate mdoclint into mandoc ("end-of-line whitespace" thread)
+  from jmc@  Mon, 13 Jul 2009 17:12:09 +0100
+  from kristaps@  Mon, 13 Jul 2009 18:34:53 +0200
+  from jmc@  Mon, 13 Jul 2009 17:45:37 +0059
+  from kristaps@  Mon, 13 Jul 2009 19:02:03 +0200
+  (mostly done, check what remains)
+
+- -Tlint parser errors and warnings to stdout
+  to tech@mdocml, naddy@  Wed, 28 Sep 2011 11:21:46 +0200
+  wait!  kristaps@  Sun, 02 Oct 2011 17:12:52 +0200
+
+************************************************************************
+* documentation issues
+************************************************************************
+
+- mention hyphenation rules:
+  breaking at letter-letter in text mode (not macro args)
+  proper hyphenation is unimplemented
+
+- talk about spacing around delimiters
+  to jmc@, kristaps@  Sat, 23 Apr 2011 17:41:27 +0200
+
+- mark macros as: page structure domain, manual domain, general text domain
+  is this useful?
+
+- mention /usr/share/misc/mdoc.template in mdoc(7)?
+
+- Is all the content from http://www.std.com/obi/BSD/doc/usd/28.tbl/tbl
+  covered in tbl(7)?
+
+************************************************************************
 * performance issues
 ************************************************************************
 
-Several areas can be cleaned up to make mandoc even faster.  These are 
+- Why are we using MAP_SHARED, not MAP_PRIVATE for mmap(2)?
+  from kristaps@  Sat, 09 Aug 2014 13:51:36 +0200
 
+Several areas can be cleaned up to make mandoc even faster.  These are
+
 - improve hashing mechanism for macros (quite important: performance)
 
 - improve hashing mechanism for characters (not as important)
 
+- the PDF file is HUGE: this can be reduced by using relative offsets
+
+- instead of re-initialising the roff predefined-strings set before each
+  parse, create a read-only version the first time and copy it
+  loc *  exist **  algo **  size *  imp **
+
 ************************************************************************
 * structural issues
 ************************************************************************
 
+- We use the input line number at several places to distinguish
+  same-line from different-line input.  That plainly doesn't work
+  with user-defined macros, leading to random breakage.
+
+- Find better ways to prevent endless loops
+  in roff(7) macro and string expansion.
+
+- Finish cleanup of date handling.
+  Decide which formats should be recognized where.
+  Update both mdoc(7) and man(7) documentation.
+  Triggered by  Tim van der Molen  Tue, 22 Feb 2011 20:30:45 +0100
+
+- struct mparse refactoring
+  Steffen Nurpmeso  Thu, 04 Sep 2014 12:50:00 +0200
+
+************************************************************************
+* CGI issues
+************************************************************************
+
+ - Enable HTTP compression by detecting gzip encoding and filtering
+   output through libz.
+ - Sandbox (see OpenSSH).
+ - Enable caching support via HTTP 304 and If-Modified-Since.
+ - Allow for cgi.h to be overridden by CGI environment variables.
+   Otherwise, binary distributions will inherit the compile-time
+   behaviour, which is not optimal.
+ - Have Mac OSX systems automatically disable -static compilation of the
+   CGI: -static isn't supported.
+
+************************************************************************
+* to improve in the groff_mdoc(7) macros
+************************************************************************
+
+- use uname(1) to set doc-default-operating-system at install time
+  tobimensch  Mon, 1 Dec 2014 00:25:07 +0100