Preprocess for older bison is no longer needed

common.mk

@@ -956,8 +956,6 @@ PHONY:
 {$(srcdir)}.y.c:
 	$(ECHO) generating $@
 	$(Q)$(BASERUBY) $(tooldir)/id2token.rb $(SRC_FILE) > parse.tmp.y
-	$(Q)$(BASERUBY) $(tooldir)/pure_parser.rb parse.tmp.y $(YACC)
-	$(Q)$(RM) parse.tmp.y.bak
 	$(Q)$(YACC) -d $(YFLAGS) -o y.tab.c parse.tmp.y
 	$(Q)$(RM) parse.tmp.y
 	$(Q)sed -f $(tooldir)/ytab.sed -e "/^#/s|parse\.tmp\.[iy]|$(SRC_FILE)|" -e "/^#/s!y\.tab\.c!$@!" y.tab.c > $@.new

ext/ripper/depend

@@ -20,8 +20,6 @@ static: check
 ripper.y: $(srcdir)/tools/preproc.rb $(srcdir)/tools/dsl.rb $(top_srcdir)/parse.y $(top_srcdir)/defs/id.def
 	$(ECHO) extracting $@ from $(top_srcdir)/parse.y
 	$(Q) $(RUBY) $(top_srcdir)/tool/id2token.rb $(top_srcdir)/parse.y > ripper.tmp.y
-	$(Q) $(RUBY) $(top_srcdir)/tool/pure_parser.rb ripper.tmp.y $(BISON)
-	$(Q) $(RM) ripper.tmp.y.bak
 	$(Q) $(RUBY) $(srcdir)/tools/preproc.rb ripper.tmp.y --output=$@
 	$(Q) $(RM) ripper.tmp.y
 

tool/pure_parser.rb

@@ -1,24 +0,0 @@
-#!/usr/bin/ruby -pi.bak
-BEGIN {
-  # pathological setting
-  ENV['LANG'] = ENV['LC_MESSAGES'] = ENV['LC_ALL'] = 'C'
-
-  require_relative 'lib/colorize'
-
-  colorize = Colorize.new
-  file = ARGV.shift
-  begin
-    version = IO.popen(ARGV+%w[--version], "rb", &:read)
-  rescue Errno::ENOENT
-    abort "Failed to run `#{colorize.fail ARGV.join(' ')}'; You may have to install it."
-  end
-  unless /\Abison .* (\d+)\.\d+/ =~ version
-    puts colorize.fail("not bison")
-    exit
-  end
-  exit if $1.to_i >= 3
-  ARGV.clear
-  ARGV.push(file)
-}
-$_.sub!(/^%define\s+api\.pure/, '%pure-parser')
-$_.sub!(/^%define\s+.*/, '')