groff with "nullptr" and (without) gnulib module causes error

[Bjarni Ingi Gislason]

Debian testing (bookworm/sid)

Linux  6.1.7-1  x86_64 GNU/Linux
 
gcc (Debian 12.2.0-14) 12.2.0

GNU Make 4.4.0.90
Built for x86_64-pc-linux-gnu

####

cd git/groff/src

grep -r -l nullptr * > $afrit

echo 's%0 /\* nullptr \*/%nullptr%' > ~/tmp/nullptr.sed

sed -i -f ~/tmp/nullptr.sed $(cat $afrit)

  Build with gnulib nullptr module or without it causes

  CXX      src/roff/troff/input.o
../src/roff/troff/input.cpp: In member function 'void token::next()':
../src/roff/troff/input.cpp:2078:18: error: invalid operands of types 'const 
char' and 'std::nullptr_t' to binary 'operator!='
 2078 |           if (*p != nullptr || s.is_empty()) {
      |               ~~~^~~~~~~~~~
make[1]: *** [Makefile:10126: src/roff/troff/input.o] Error 1
make[1]: Leaving directory '/home/bg/git/groff/build'
make: *** [Makefile:6847: all] Error 2

####

"bootstrap.conf" with "nullptr"

gnulib_modules="
    git-version-gen
    havelib
    manywarnings
    wcwidth
    fprintf-posix
    gen-header
    snprintf
    vsnprintf-posix
    warnings
  mkstemp
  fmod
  getcwd
  putenv
  strcase
  strerror
  strtol
  setlocale
  stdckdint
  assert
  assert-h
  idx
  string
  strings
  nullptr
 "