the source or/and the header output file extension.
* src/files.c (compute_base_names): Remove initialisation of
src_extension and header_extension.
(compute_exts_from_gf): Update.
(compute_exts_from_src): Update.
(output_files): Update.
* src/reader.c (parse_header_extension_decl): New.
(parse_source_extension_decl): New.
(read_declarations): New case statements for the new tokens.
* src/lex.c (percent_table): Add entries for %source_extension
and %header_extension.
* src/lex.h (token_e): New tokens tok_hdrext and tok_srcext.
New, from fileutils 4.0.37.
* configure.in: Require Autoconf 2.49c. I took some time before
making this decision. This is the only way out for portability
issues in Bison, it would mean way too much duplicate effort to
import in Bison features implemented in 2.49c since 2.13.
AC_REPLACE_FUNCS and AC_CHECK_DECLS the functions above.