[Groff] compile problem - groff-1.18: input.cc

[Ayamura KIKUCHI]

Compilation errors given below occur.
Source - Groff 1.18
Platform - IRIX 6.5.16f with MIPSpro Compilers 7.3.1.3m

% CC -n32 -I. -I/work/groff-1.18/src/libs/libdriver \
-I/work/groff-1.18/src/include -I/work/groff-1.18/src/include \
-DHAVE_CONFIG_H -O2 -OPT:Olimit=0 -w -c input.cc

cc-1392 CC: ERROR File = input.cc, Line = 913
  More than one conversion function from "Char" to a built-in type applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
         && c != Char('\n') && c != Char(EOF)) {
            ^

cc-1392 CC: ERROR File = input.cc, Line = 913
  More than one conversion function from "Char" to a built-in type applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
         && c != Char('\n') && c != Char(EOF)) {
                 ^

cc-1392 CC: ERROR File = input.cc, Line = 913
  More than one conversion function from "Char" to a built-in type applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
         && c != Char('\n') && c != Char(EOF)) {
                               ^

cc-1392 CC: ERROR File = input.cc, Line = 913
  More than one conversion function from "Char" to a built-in type applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
         && c != Char('\n') && c != Char(EOF)) {
                                    ^

cc-1392 CC: ERROR File = input.cc, Line = 932
  More than one conversion function from "const Char" to a built-in type 
applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
    return (c == (Char) ' ' || c == (Char) '\t') ? true : false;
            ^

cc-1392 CC: ERROR File = input.cc, Line = 932
  More than one conversion function from "Char" to a built-in type applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
    return (c == (Char) ' ' || c == (Char) '\t') ? true : false;
                 ^

cc-1392 CC: ERROR File = input.cc, Line = 932
  More than one conversion function from "const Char" to a built-in type 
applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
    return (c == (Char) ' ' || c == (Char) '\t') ? true : false;
                               ^

cc-1392 CC: ERROR File = input.cc, Line = 932
  More than one conversion function from "Char" to a built-in type applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
    return (c == (Char) ' ' || c == (Char) '\t') ? true : false;
                                    ^

cc-1392 CC: ERROR File = input.cc, Line = 1229
  More than one conversion function from "const Char" to a built-in type 
applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
    if (c != EOF) {
        ^

cc-1392 CC: ERROR File = input.cc, Line = 1617
  More than one conversion function from "Char" to a built-in type applies.

            Function symbol function "Char::operator int() const" is ambiguous
                      by inheritance.
            Function symbol function "Char::operator unsigned char() const" is
                      ambiguous by inheritance.
            Function symbol function "Char::operator char() const" is
                      ambiguous by inheritance.
      if (command != 'x')
          ^

-- ayamura