Cross build error on the host-m4-1.4.17

[carloscn]

An error is prompted when I cross-compile buildroot-ostree, the log is shown in the following text block:

freadahead.c: In function 'freadahead':
freadahead.c:92:3: error: #error "Please port gnulib freadahead.c to your platform! Look at the definition of fflush, fread, ungetc on your system, then report this to bug-gnulib."
   92 |  #error "Please port gnulib freadahead.c to your platform! Look at the definition of fflush, fread, ungetc on your system, then report this to bug-gnulib."
      |   ^~~~~
make[4]: *** [Makefile:1915: freadahead.o] Error 1
make[4]: *** Waiting for unfinished jobs....
fseeko.c: In function 'rpl_fseeko':
fseeko.c:110:4: error: #error "Please port gnulib fseeko.c to your platform! Look at the code in fseeko.c, then report this to bug-gnulib."
  110 |   #error "Please port gnulib fseeko.c to your platform! Look at the code in fseeko.c, then report this to bug-gnulib."
      |    ^~~~~
make[4]: *** [Makefile:1915: fseeko.o] Error 1

I have worked around this issue by:

$ cd ./buildroot-ostree/output/build/host-m4-1.4.17
$ sed -i 's/IO_ftrylockfile/IO_EOF_SEEN/' lib/*.c
$ echo "#define _IO_IN_BACKUP 0x100" >> lib/stdio-impl.h