m4 bug

[carl hansen]

building m4 from source gcc version 8.3.0 (Debian 8.3.0-19)
debian bullseye

depbase=`echo freadahead.o | sed 's|[^/]*$|.deps/&|;s|\.o$||'`;\
gcc  -I.     -g -O2 -MT freadahead.o -MD -MP -MF $depbase.Tpo -c -o
freadahead.o freadahead.c &&\
mv -f $depbase.Tpo $depbase.Po
depbase=`echo fseeko.o | sed 's|[^/]*$|.deps/&|;s|\.o$||'`;\
gcc  -I.     -g -O2 -MT fseeko.o -MD -MP -MF $depbase.Tpo -c -o
fseeko.o fseeko.c &&\
mv -f $depbase.Tpo $depbase.Po
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."
   #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:1910: fseeko.o] Error 1
make[4]: *** Waiting for unfinished jobs....
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."
  #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:1910: freadahead.o] Error 1