Fix for PR automake/322: * automake.in (read_am_file): Rename $was_rule as $prev_state, and set it with IN_RULE_DEF, IN_VAR_DEF, or IN_COMMENT as appropriate. Handle comments continued by backslashes. * tests/comment6.test: New file. * tests/Makefile.am (TESTS): Add comment6.test. Reported by Braden N. McDaniel.