AC_DEFUN([adl_CHECK_BISON], [AC_ARG_VAR([BISON], [Bison parser generator]) AC_CHECK_PROGS([BISON], [bison]) if test -n "$BISON"; then # Bison 3.0 has warning about issues that cannot be fixed in a # compatible way with Bison 2.7. Since we want to be compatible # with both version AND use -Werror, disable those warnings. # (Unfortunately -Wno-error=empty-rule,no-error=deprecated does not # work: https://lists.gnu.org/archive/html/bug-bison/2013-09/index.html) opt='-Wno-empty-rule -Wno-deprecated -Wno-precedence' if AM_RUN_LOG([$BISON $opt --version]); then BISON_EXTRA_FLAGS=$opt fi fi AC_SUBST([BISON_EXTRA_FLAGS])])