Compiler warning: integer conversion resulted in a change of sign

[jczhang07]

Hello, with PGI compiler (nvc), I met these kind of warnings:

"~/yaml/src/scanner.c", line 3181: warning: integer conversion resulted in a change of sign
                          *(string.pointer++) = '\xC2';
                                                ^
...

"~/yaml/src/scanner.c", line 3199: warning: integer conversion resulted in a change of sign
                          *(string.pointer++) = '\xA9';
                                                ^