Re: Links in WoMan buffer should not call `man'

[Juri Linkov <juri@jurta.org>]

>     the last command typed in the woman's dedicated frame fails with the error
>     signalled by string-match:
>
>       Man-translate-references: Wrong type argument: arrayp, nil
>
> How about debugging it?  This sounds like something straightforward
> to debug.

I narrowed it to the simplest case.  This error occurs only when `M-x man'
is executed in the *Messages* buffer.  (The shortest key sequence to
reproduce it: `C-h e M-x man RET man RET')

Putting the gdb breakpoint on `wrong_type_argument' gives the following bt:

#0  wrong_type_argument (predicate=137953905, value=137897977) at data.c:121
#1  0x0818d95c in Faref (array=137897977, idx=17768) at data.c:2082
#2  0x081ae982 in char_table_translate (table=137897977, ch=2221) at fns.c:2789
#3  0x0817129f in set_image_of_range_1 (work_area=0xbfcfa4b4, start=2221, end=2221, translate=137923116) at regex.c:2132
#4  0x08171a55 in set_image_of_range (work_area=0xbfcfa4b4, start=2221, end=2221, translate=137923116) at regex.c:2262
#5  0x08174968 in regex_compile (pattern=0x8927b78 "^\\([-a-zA-Z0-9_\201\255+][-a-zA-Z0-9_.:\201\255+]*\\)(\\([0-9][a-zA-Z+]*\\|[LNln]\\))$", size=70, syntax=3408388, 
    bufp=0x8373c4c) at regex.c:2973
#6  0x08181f70 in re_compile_pattern (pattern=0x8927b78 "^\\([-a-zA-Z0-9_\201\255+][-a-zA-Z0-9_.:\201\255+]*\\)(\\([0-9][a-zA-Z+]*\\|[LNln]\\))$", length=70, 
    bufp=0x8373c4c) at regex.c:6165
#7  0x08168751 in compile_pattern_1 (cp=0x8373c40, pattern=141439291, translate=137923116, regp=0x836ace8, posix=0, multibyte=1) at search.c:173
#8  0x08168976 in compile_pattern (pattern=141439291, regp=0x836ace8, translate=137923116, posix=0, multibyte=1) at search.c:248
#9  0x08168f21 in string_match_1 (regexp=141439291, string=141439307, start=137897977, posix=0) at search.c:400
#10 0x081690b3 in Fstring_match (regexp=141439291, string=141439307, start=137897977) at search.c:443
(gdb) fr 3
#3  0x0817129f in set_image_of_range_1 (work_area=0xbfcfa4b4, start=2221, end=2221, translate=137923116) at regex.c:2132
2132          int eqv = RE_TRANSLATE (eqv_table, start);
(gdb) xprintsym eqv_table
"nil"

i.e. eqv_table in the *Messages* buffer is nil.

I have no idea why it should be nil in the *Messages* buffer,
but `Man-translate-references' fails when it tries to run
`string-match' in this buffer.

-- 
Juri Linkov
http://www.jurta.org/emacs/