maint: avoid \] in REs

* cfg.mk (sc_dd_max_sym_length, sc_prohibit_man_see_also_period):
Do not rely on undefined interpretation of \] in regular expressions.

cfg.mk

@@ -76,8 +76,8 @@ sc_dd_O_FLAGS:
 dd_c = $(srcdir)/src/dd.c
 sc_dd_max_sym_length:
 ifneq ($(wildcard $(dd_c)),)
-	@len=$$( (sed -n '/conversions\[\] =$$/,/^};/p' $(dd_c);\
-		 sed -n '/flags\[\] =$$/,/^};/p' $(dd_c) )	\
+	@len=$$( (sed -n '/conversions\[] =$$/,/^};/p' $(dd_c);\
+		 sed -n '/flags\[] =$$/,/^};/p' $(dd_c) )	\
 		|sed -n '/"/s/^[^"]*"\([^"]*\)".*/\1/p'| wc -L);\
 	max=$$(sed -n '/^#define LONGEST_SYMBOL /s///p' $(dd_c)	\
 	      |tr -d '"' | wc -L);		\
@@ -496,7 +496,7 @@ sc_ensure_comma_after_id_est:
 # a period.  Check the first line after each "SEE ALSO" line in man/*.x:
 sc_prohibit_man_see_also_period:
 	@grep -nB1 '\.$$' $$($(VC_LIST_EXCEPT) | grep 'man/.*\.x$$')	\
-	    | grep -A1 -e '-\[SEE ALSO\]' | grep '\.$$' &&		\
+	    | grep -A1 -e '-\[SEE ALSO]' | grep '\.$$' &&		\
 	  { echo '$(ME): do not end "SEE ALSO" section with a period'	\
 	      1>&2; exit 1; } || :
 

src/fmt.c

@@ -672,7 +672,7 @@ same_para (int c)
 /* Read a line from input file F, given first non-blank character C
    after the prefix, and the following indent, and break it into words.
    A word is a maximal non-empty string of non-white characters.  A word
-   ending in [.?!]["')\]]* and followed by end-of-line or at least two
+   ending in [.?!][])"']* and followed by end-of-line or at least two
    spaces ends a sentence, as in emacs.
 
    Return the first non-blank character of the next line.  */

src/tr.c

@@ -825,7 +825,7 @@ find_bracketed_repeat (const struct E_string *es, size_t start_idx,
 }
 
 /* Return true if the string at ES->s[IDX] matches the regular
-   expression '\*[0-9]*\]', false otherwise.  The string does not
+   expression '\*[0-9]*]', false otherwise.  The string does not
    match if any of its characters are escaped.  */
 
 ATTRIBUTE_PURE
@@ -942,7 +942,7 @@ build_spec_list (const struct E_string *es, struct Spec_list *result)
         try_bracketed_repeat:
 
           /* Determine whether this is a bracketed repeat range
-             matching the RE \[.\*(dec_or_oct_number)?\].  */
+             matching the RE \[.\*(dec_or_oct_number)?].  */
           err = find_bracketed_repeat (es, i + 1, &char_to_repeat,
                                        &repeat_count,
                                        &closing_bracket_idx);