/usr/bin/sed: can't read css_tokenizer.c

Hi,

Doing a "make distclean" removes libwget/css_tokenizer.c. Here are the steps that reproduce the problem for me.

tar -xf wget2-latest.tar.gz
cd wget2-2.1.0
./configure

libwget/css_tokenizer.c is present at this point.

make distclean

libwget/css_tokenizer.c is no longer present when listing the files in the libwget directory. Attempting to configure and make fails.

./configure
  ...
  CC       libwget_la-xml.lo
  CC       libwget_la-http_highlevel.lo
  CC       libwget_la-error.lo
  CC       libwget_la-dns.lo
  CC       libwget_la-ssl_openssl.lo
  CC       libwget_la-ssl.lo
  GEN      css_tokenizer.c
/usr/bin/sed: can't read css_tokenizer.c: No such file or directory
make[2]: *** [Makefile:4912: css_tokenizer.c] Error 2
make[2]: Leaving directory '/home/code/Source/wget2-2.1.0/libwget'
make[1]: *** [Makefile:2128: all-recursive] Error 1
make[1]: Leaving directory '/home/code/Source/wget2-2.1.0'
make: *** [Makefile:2036: all] Error 2

This is the narrowest case I can come up with to exhibit the problem. Note "make clean" doesn't remove the file, only "make distclean".