Re: Patch bison for M4 arguments

[Akim Demaille]

   Hi Barry,

     Le 16 oct. 2018 A  15:41, Barry Davis <address@hidden> a
     A(c)crit :
     Bison runs M4. It adds BISON_PKGDATADIR to the search path for M4
     and
     launches M4 to run on m4sugar/m4sugar.m4. m4sugar
     includes m4sugar/foreach.m4 which is found on M4s search path.
     Somewhere along the line we include c.m4 which
     includes b4_pkgdatadir/[c-like.m4], but M4 doesn't know the
     b4_pkgdatadir
     variable and so fails to include.

   Yes, it does.  It is given to m4 via stdin.
   $ ln -s data hello-world
   $ BISON_PKGDATADIR=hello-world /opt/local/bin/bison aEUR"trace=m4
   /tmp/foo.y |& grep b4_pkgdatadir
   m4trace:stdin:315: -1- id 3238: m4_define([b4_pkgdatadir],
   [[hello-world]]) -> ???
   m4trace:hello-world/c-skel.m4:21: -1- id 3879:
   b4_glr_if([m4_define([b4_used_skeleton], [b4_pkgdatadir/[glr.c]])]) ->
   ???
   m4trace:hello-world/c-skel.m4:21: -1- id 3879: b4_glr_if(...) ->
   [b4_flag_if([glr], [m4_define([b4_used_skeleton],
   [b4_pkgdatadir/[glr.c]])], [])]
   m4trace:hello-world/c-skel.m4:21: -1- id 3880: b4_flag_if([glr],
   [m4_define([b4_used_skeleton], [b4_pkgdatadir/[glr.c]])], []) -> ???
           [1], [m4_define([b4_used_skeleton], [b4_pkgdatadir/[glr.c]])],
   m4trace:hello-world/c-skel.m4:21: -1- id 3881: m4_case([0], [0], [],
   [1], [m4_define([b4_used_skeleton], [b4_pkgdatadir/[glr.c]])],
   [m4_fatal([invalid glr value: ]b4_glr_flag)]) -> ???
   [_m4_case])]m4_dquote($m4_eval([(6 + 1) &
   ~1]))[)])_m4_case([0],[0],[],[1],[m4_define([b4_used_skeleton],
   [b4_pkgdatadir/[glr.c]])],[m4_fatal([invalid glr value:
   ]b4_glr_flag)])])]
   [_m4_case])]m4_dquote($m4_eval([(6 + 1) &
   ~1]))[)])_m4_case([0],[0],[],[1],[m4_define([b4_used_skeleton],
   [b4_pkgdatadir/[glr.c]])],[m4_fatal([invalid glr value:
   ]b4_glr_flag)])]) -> ???
   [_m4_case])]m4_dquote($m4_eval([(6 + 1) &
   ~1]))[)])_m4_case([0],[0],[],[1],[m4_define([b4_used_skeleton],
   [b4_pkgdatadir/[glr.c]])],[m4_fatal([invalid glr value:
   ]b4_glr_flag)])]
   aEUR|
   This is used extensively by the test suite to check a non-installed
   bison.

     I've seen this building krb5-1.16.1 in a cross environment where
     bison-3.1
     is installed and ran from a staging area with the environment
     variables M4
     and BISON_PKGDATADIR set.

   Was it set to the appropriate value?
   Could you provide us with more details about that?