Using Bison with the GNU Build System

Autoconf and Automake provide some generic Yacc support, but no Bison dedicated support. In particular Automake expects y.tab.c and y.tab.h as output files, which makes it go through various hoops to prevent several concurrent invocations of yacc to overwrite each others' output.

As Gperf, Lex, and Flex, Yacc and Bison are maintainer requirements: someone changing the package needs them, but since their result is shipped, a regular user does not need them. Really, don't bother with different Yaccs, Bison alone will satisfy all your needs, and if it doesn't, just improve it!

If you use Autoconf's AC_PROG_YACC, then if bison is found, it sets YACC to bison --yacc, otherwise to byacc if it exist, otherwise to yacc. It seems so much simpler to simply set YACC to bison! But then you lose the assistance of Automake, and in particular of missing (voir Using Gperf with the GNU Build System). So I suggest simply sticking to AC_PROG_YACC, and let Automake handle the rest.

Then, in your Makefile.am, merely list Bison sources as ordinary source files:

     LDFLAGS = -no-undefined
     
     pkglibexec_LTLIBRARIES	= yleval.la
     yleval_la_SOURCES = ylparse.y ylscan.l yleval.c yleval.h ylparse.h
     yleval_la_LDFLAGS = -module
     

and that's all.