Implicit declarations of C functions -- error when running go get

[mdayaram]

When running go get in OSX Mavericks, it appears some people are getting the following errors:

go get -u github.com/moovweb/gokogiri
github.com/moovweb/gokogiri/xml
go/src/github.com/moovweb/gokogiri/xml/helper.c:7:3: warning: implicit declaration of function 'xmlNodeWriteCallback' is invalid in C99 [-Wimplicit-function-declaration]
go/src/github.com/moovweb/gokogiri/xml/helper.c:106:8: warning: initializing 'char *' with an expression of type 'xmlChar *' (aka 'unsigned char *') converts between pointers to integer types with different sign [-Wpointer-sign]
go/src/github.com/moovweb/gokogiri/xml/helper.c:112:4: warning: implicit declaration of function 'xmlUnlinkNodeCallback' is invalid in C99 [-Wimplicit-function-declaration]

Some more info on issue #53