m4 ChangeLog NEWS doc/m4.texinfo src/builtin.c ... [branch-1_4]

[Eric Blake]

CVSROOT:        /sources/m4
Module name:    m4
Branch:         branch-1_4
Changes by:     Eric Blake <ericb>      06/06/22 23:17:22

Modified files:
        .              : ChangeLog NEWS 
        doc            : m4.texinfo 
        src            : builtin.c freeze.c m4.h 

Log message:
        Robustify frozen file format.
        * src/freeze.c (reload_frozen_state): Add GET_DIRECTIVE helper
        macro.  Require V first, and only accept it once.  For F, use
        placeholder if builtin is not found, rather than warning.
        * src/m4.h (m4_placeholder): New prototype.
        * src/builtin.c: Unify error message style.
        (m4_placeholder): New function, warn if invoked.
        (builtin_tab): Add m4_placeholder.
        (m4_defn): Warn if placeholder is encountered.
        (find_builtin_by_addr): Handle placeholder.
        (find_builtin_by_name): Return placeholder on failure.
        (m4_builtin): Treat placeholder as undefined.
        * doc/m4.texinfo (Frozen files): Document changes in V and F.
        * NEWS: Document this change.
        Reported by Bruno Haible.

CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/m4/ChangeLog?cvsroot=m4&only_with_tag=branch-1_4&r1=1.1.1.1.2.81&r2=1.1.1.1.2.82
http://cvs.savannah.gnu.org/viewcvs/m4/NEWS?cvsroot=m4&only_with_tag=branch-1_4&r1=1.1.1.1.2.23&r2=1.1.1.1.2.24
http://cvs.savannah.gnu.org/viewcvs/m4/doc/m4.texinfo?cvsroot=m4&only_with_tag=branch-1_4&r1=1.1.1.1.2.22&r2=1.1.1.1.2.23
http://cvs.savannah.gnu.org/viewcvs/m4/src/builtin.c?cvsroot=m4&only_with_tag=branch-1_4&r1=1.1.1.1.2.12&r2=1.1.1.1.2.13
http://cvs.savannah.gnu.org/viewcvs/m4/src/freeze.c?cvsroot=m4&only_with_tag=branch-1_4&r1=1.1.1.1.2.5&r2=1.1.1.1.2.6
http://cvs.savannah.gnu.org/viewcvs/m4/src/m4.h?cvsroot=m4&only_with_tag=branch-1_4&r1=1.1.1.1.2.11&r2=1.1.1.1.2.12