Merge remote-tracking branch 'origin/maint'

Merge remote-tracking branch 'origin/maint'

* origin/maint: (46 commits)
  doc: minor style change
  maint: use gendocs's new -I option
  regen
  yacc.c: do not define location support when not using locations
  maint: be compilable with GCC 4.0
  tests: address a warning from GCC 4.4
  tests: don't use options that Clang does not support
  tests: restore the tests on -Werror
  regen
  parse-gram: update the Bison interface
  fix comment
  maint: post-release administrivia
  version 2.6.4
  regen
  2.6.4: botched 2.6.3
  maint: post-release administrivia
  version 2.6.3
  gnulib: update
  tests: check %no-lines
  NEWS: warnings with clang
  ...

Conflicts:
	NEWS
	TODO
	data/c.m4
	data/java.m4
	doc/Makefile.am
	src/getargs.c
	src/getargs.h
	src/output.c
	src/parse-gram.c
	src/parse-gram.h
	src/parse-gram.y
	src/reader.h