int re_yylex_init(yyscan_t* ptr_yy_globals)

{
    if (ptr_yy_globals == NULL){
        errno = EINVAL;
        return 1;
    }

    *ptr_yy_globals = (yyscan_t) re_yyalloc ( sizeof( struct yyguts_t ), NULL );

    if (*ptr_yy_globals == NULL){
        errno = ENOMEM;
        return 1;
    }

    /* By setting to 0xAA, we expose bugs in yy_init_globals. Leave at 0x00 for releases. */
    memset(*ptr_yy_globals,0x00,sizeof(struct yyguts_t));

    return yy_init_globals ( *ptr_yy_globals );
}

The product dereferences a pointer that it expects to be valid but is NULL.