We are preparing Ruby 3.4 [1] for Fedora and we have identifies that the package is going to break due to upstream change [2]. The specific error looks like:

~~~
... snip ...

gcc -I. -I/usr/include -I/usr/include/ruby/backward -I/usr/include -I. -DHAVE_TERMIOS_H -DHAVE_UNISTD_H    -fPIC -O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Wno-complain-wrong-lang -Werror=format-security -Wp,-U_FORTIFY_SOURCE,-D_FORTIFY_SOURCE=3 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -m64 -march=x86-64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -mtls-dialect=gnu2 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -DOS_LINUX -m64 -o posix_serialport_impl.o -c posix_serialport_impl.c
posix_serialport_impl.c: In function ‘get_fd_helper’:
posix_serialport_impl.c:74:4: warning: ‘fd’ is deprecated: rb_io_descriptor [-Wdeprecated-declarations]
   74 |    return (fptr->fd);
      |    ^~~~~~
In file included from serialport.h:26,
                 from posix_serialport_impl.c:21:
/usr/include/ruby/io.h:154:9: note: declared here
  154 |     int fd;
      |         ^~
posix_serialport_impl.c: In function ‘sp_create_impl’:
posix_serialport_impl.c:112:4: error: implicit declaration of function ‘NEWOBJ’ [-Wimplicit-function-declaration]
  112 |    NEWOBJ(sp, struct RFile);
      |    ^~~~~~
posix_serialport_impl.c:112:11: error: ‘sp’ undeclared (first use in this function); did you mean ‘fp’?
  112 |    NEWOBJ(sp, struct RFile);
      |           ^~
      |           fp
posix_serialport_impl.c:112:11: note: each undeclared identifier is reported only once for each function it appears in
posix_serialport_impl.c:112:15: error: expected expression before ‘struct’
  112 |    NEWOBJ(sp, struct RFile);
      |               ^~~~~~
posix_serialport_impl.c:170:4: warning: ‘fd’ is deprecated: rb_io_descriptor [-Wdeprecated-declarations]
  170 |    fp->fd = fd;
      |    ^~
/usr/include/ruby/io.h:154:9: note: declared here
  154 |     int fd;
      |         ^~
posix_serialport_impl.c:174:4: warning: ‘mode’ is deprecated: rb_io_mode [-Wdeprecated-declarations]
  174 |    fp->mode = FMODE_READWRITE | FMODE_SYNC;
      |    ^~
/usr/include/ruby/io.h:158:9: note: declared here
  158 |     int mode;
      |         ^~~~
posix_serialport_impl.c:177:1: warning: control reaches end of non-void function [-Wreturn-type]
  177 | }
      | ^
make: *** [Makefile:252: posix_serialport_impl.o] Error 1
~~~

And I wonder what is the future of this package, if it is worth of fixing, given upstream support [3]. So I thought I'll open this ticket as an early warning.


[1] https://fedoraproject.org/wiki/Changes/Ruby_3.4
[2] https://bugs.ruby-lang.org/issues/20265
[3] https://github.com/hparra/ruby-serialport/discussions/77

Reproducible: Always