Build error with gcc 15.0 and kernel rt 5.10.233.rt125

[Yann Collette <ycollette.nospam@xxxxxxx>]

Hello,

I met a build error while building the kernel rt 5.10.233-rt125 on 
Fedora rawhide with gcc-15.0.1.
It looks like gcc-15.0.1 switched to C23.

Here is the error message:

  CC      arch/x86/realmode/rm/wakemain.o
In file included from ./include/uapi/linux/posix_types.h:5,
                 from ./include/uapi/linux/types.h:14,
                 from ./include/linux/types.h:6,
                 from arch/x86/realmode/rm/wakeup.h:11,
                 from arch/x86/realmode/rm/wakemain.c:2:
./include/linux/stddef.h:11:9: error: cannot use keyword ‘false’ as 
enumeration constant
   11 |         false   = 0,
      |         ^~~~~
./include/linux/stddef.h:11:9: note: ‘false’ is a keyword with 
‘-std=c23’ onwards
./include/linux/types.h:30:33: error: ‘bool’ cannot be defined via 
‘typedef’
   30 | typedef _Bool                   bool;
      |                                 ^~~~
./include/linux/types.h:30:33: note: ‘bool’ is a keyword with 
‘-std=c23’ onwards
./include/linux/types.h:30:1: warning: useless type name in empty 
declaration
   30 | typedef _Bool                   bool;
      | ^~~~~~~
make[3]: *** [scripts/Makefile.build:286: 
arch/x86/realmode/rm/wakemain.o] Error 1
make[2]: *** [arch/x86/realmode/Makefile:23: 
arch/x86/realmode/rm/realmode.bin] Error 2
make[1]: *** [scripts/Makefile.build:503: arch/x86/realmode] Error 2
make[1]: *** Waiting for unfinished jobs....

Best regards,

Yann