cproto reports numerous error messages when it processes some of the
standard C library
header files.  These files are processed because of their direct or
indirect inclusion in a
specified source file.  The errors occur without passing any options to
cproto, i.e.
"cproto *.c > protos".  cproto seems to successfully process the specified
source files
despite reporting dozens of parse errors in /usr/include/bits/types.h,
/usr/include/libio.h,
/usr/include/stdio.h, /usr/include/sys/types.h, /usr/include/fcntl.h, and
probably others.
Many, but not all, of the errors seemed to be related to internally defined
types, such as
__uid_t and __u_int.  I have assigned "low" severity to this bug because it
does not seem
to interfere with the program performing its function, but the multitude of
error messages is
likely to confuse and alarm some users.

I'm using cproto 4.6-3 and glibc-devel 2.1.3-19.