Merge remote-tracking branch 'origin/maint'

* origin/maint:
  headers: move CPP guards into YY_*_INCLUDED to avoid collisions
  minor changes.

Conflicts:
	doc/bison.texi
	tests/headers.at

diff --cc NEWS
Simple merge

diff --cc data/c.m4
Simple merge

diff --cc doc/bison.texi
Simple merge

diff --cc tests/headers.at
index 22f6000,0524340..df0c058
--- 1/tests/headers.at
--- 2/tests/headers.at
+++ b/tests/headers.at
@@@ -165,17 -167,17 +167,18 @@@ AT_BISON_CHECK([-d -o AT_SKEL_CC_IF([$1
  AT_SKEL_CC_IF([],
    [AT_CHECK([$EGREP yy $1.h], [1])])
  
- # Ignore comments. Ignore YYPUSH_MORE(_DEFINED)? (whose definition
- # is constant).
+ # Check there is not 'YY' left.
 -# Ignore comments, YYPARSE_PARAM (obsolete), YYPUSH_MORE(_DEFINED)?
 -# (constant definition), YY_\w+_INCLUDED (header guards).
++# Ignore comments, YYPUSH_MORE(_DEFINED)?  (constant definition),
++# YY_\w+_INCLUDED (header guards).
  #
  # YYDEBUG (not renamed) can be read, but not changed.
 -AT_CHECK([[sed -ne 's,/\*[^*]*\*/,,g;s,//.*,,' \
 -                -e '/YY/p' ]$1.AT_SKEL_CC_IF([hh], [h])[ |
 -     $EGREP -wv 'YY(PARSE_PARAM|PUSH_MORE(_DEFINED)?|_[0-9A-Z_]+_INCLUDED)|(defined|if) YYDEBUG']],
 +AT_CHECK([[$PERL -0777 -e 's{/\*.*?\*/}{}sg;s,//.*,,;' \
 +            ]$1.AT_SKEL_CC_IF([hh], [h])[ |
 +         grep 'YY' |
-      $EGREP -wv 'YYPUSH_MORE(_DEFINED)?|(defined|if) YYDEBUG']],
++     $EGREP -wv 'YY(PUSH_MORE(_DEFINED)?|_[0-9A-Z_]+_INCLUDED)|(defined|if) YYDEBUG']],
           [1])
- AT_LANG_COMPILE([$1.o])
  
+ AT_LANG_COMPILE([$1.o])
  AT_CHECK([[echo "$1" >>expout]])
  
  AT_BISON_OPTION_POPDEFS