To comply with the latest POSIX standard, in Yacc compatibility mode
(options -y/--yacc) Bison now generates prototypes for yyerror and
yylex. In some situations, this is breaking compatibility: if the user
has already declared these functions but with some differences (e.g., to
declare them as static, or to use specific attributes), the generated
parser will fail to compile. To disable these prototypes, #define yyerror
(to yyerror), and likewise for yylex.
thom311
commented
2 years ago
To comply with the latest POSIX standard, in Yacc compatibility mode (options
-y/--yacc) Bison now generates prototypes for yyerror and yylex. In some situations, this is breaking compatibility: if the user has already declared these functions but with some differences (e.g., to declare them as static, or to use specific attributes), the generated parser will fail to compile. To disable these prototypes, #define yyerror (toyyerror), and likewise for yylex.refer: https://git.savannah.gnu.org/cgit/bison.git/tree/NEWS
GNU Bison 3.8
Issue #294 has the details of the errors