There is a file pig.go on the golang.org website:
http://golang.org/doc/codewalk/functions/
in a box labeled doc/codewalk/pig.go
Compiling it with gccgo version (Ubuntu/Linaro 4.6.1-9ubuntu3) 4.6.1
gccgo pig.go
gives an error message about not finding math/rand
pig.go:9:11: error: import file ‘math/rand’ not found