% go version
go version devel +46db2dd7ba7c Wed Feb 06 00:33:25 2013 +0800 darwin/amd64
% cd $GOROOT/src/pkg
% go vet ./crypto/rand
vet: rand_windows.go: open rand_windows.go: no such file or directory
exit status 2
% cd crypto/rand/
% pwd
$GOROOT/src/pkg/crypto/rand
% go vet
% echo $?
0

The problem is that when running ``go vet`` from outside the package, it returns
"no such file or directory" for files that would not be linked with the
package (I'm on Darwin, so rand_windows.go is ignored). Here is the output for the
syscall package:

% go vet syscall
vet: creds_test.go: open creds_test.go: no such file or directory
vet: dir_plan9.go: open dir_plan9.go: no such file or directory
vet: dll_windows.go: open dll_windows.go: no such file or directory
vet: env_plan9.go: open env_plan9.go: no such file or directory
vet: env_windows.go: open env_windows.go: no such file or directory
vet: exec_linux.go: open exec_linux.go: no such file or directory
vet: exec_plan9.go: open exec_plan9.go: no such file or directory
vet: exec_windows.go: open exec_windows.go: no such file or directory
vet: lsf_linux.go: open lsf_linux.go: no such file or directory
vet: netlink_linux.go: open netlink_linux.go: no such file or directory
vet: race.go: open race.go: no such file or directory
vet: route_freebsd.go: open route_freebsd.go: no such file or directory
vet: route_netbsd.go: open route_netbsd.go: no such file or directory
vet: route_openbsd.go: open route_openbsd.go: no such file or directory
vet: security_windows.go: open security_windows.go: no such file or directory
vet: sockcmsg_linux.go: open sockcmsg_linux.go: no such file or directory
vet: syscall_darwin_386.go: open syscall_darwin_386.go: no such file or directory
vet: syscall_freebsd.go: open syscall_freebsd.go: no such file or directory
vet: syscall_freebsd_386.go: open syscall_freebsd_386.go: no such file or directory
vet: syscall_freebsd_amd64.go: open syscall_freebsd_amd64.go: no such file or directory
vet: syscall_freebsd_arm.go: open syscall_freebsd_arm.go: no such file or directory
vet: syscall_linux.go: open syscall_linux.go: no such file or directory
vet: syscall_linux_386.go: open syscall_linux_386.go: no such file or directory
vet: syscall_linux_amd64.go: open syscall_linux_amd64.go: no such file or directory
vet: syscall_linux_arm.go: open syscall_linux_arm.go: no such file or directory
vet: syscall_netbsd.go: open syscall_netbsd.go: no such file or directory
vet: syscall_netbsd_386.go: open syscall_netbsd_386.go: no such file or directory
vet: syscall_netbsd_amd64.go: open syscall_netbsd_amd64.go: no such file or directory
vet: syscall_openbsd.go: open syscall_openbsd.go: no such file or directory
vet: syscall_openbsd_386.go: open syscall_openbsd_386.go: no such file or directory
vet: syscall_openbsd_amd64.go: open syscall_openbsd_amd64.go: no such file or directory
vet: syscall_plan9.go: open syscall_plan9.go: no such file or directory
vet: syscall_plan9_386.go: open syscall_plan9_386.go: no such file or directory
vet: syscall_plan9_amd64.go: open syscall_plan9_amd64.go: no such file or directory
vet: syscall_windows.go: open syscall_windows.go: no such file or directory
vet: syscall_windows_386.go: open syscall_windows_386.go: no such file or directory
vet: syscall_windows_amd64.go: open syscall_windows_amd64.go: no such file or directory
vet: syscall_windows_test.go: open syscall_windows_test.go: no such file or directory
vet: types_darwin.go: open types_darwin.go: no such file or directory
vet: types_freebsd.go: open types_freebsd.go: no such file or directory
vet: types_linux.go: open types_linux.go: no such file or directory
vet: types_netbsd.go: open types_netbsd.go: no such file or directory
vet: types_openbsd.go: open types_openbsd.go: no such file or directory
vet: zerrors_darwin_386.go: open zerrors_darwin_386.go: no such file or directory
vet: zerrors_freebsd_386.go: open zerrors_freebsd_386.go: no such file or directory
vet: zerrors_freebsd_amd64.go: open zerrors_freebsd_amd64.go: no such file or directory
vet: zerrors_freebsd_arm.go: open zerrors_freebsd_arm.go: no such file or directory
vet: zerrors_linux_386.go: open zerrors_linux_386.go: no such file or directory
vet: zerrors_linux_amd64.go: open zerrors_linux_amd64.go: no such file or directory
vet: zerrors_linux_arm.go: open zerrors_linux_arm.go: no such file or directory
vet: zerrors_netbsd_386.go: open zerrors_netbsd_386.go: no such file or directory
vet: zerrors_netbsd_amd64.go: open zerrors_netbsd_amd64.go: no such file or directory
vet: zerrors_openbsd_386.go: open zerrors_openbsd_386.go: no such file or directory
vet: zerrors_openbsd_amd64.go: open zerrors_openbsd_amd64.go: no such file or directory
vet: zerrors_plan9_386.go: open zerrors_plan9_386.go: no such file or directory
vet: zerrors_plan9_amd64.go: open zerrors_plan9_amd64.go: no such file or directory
vet: zerrors_windows.go: open zerrors_windows.go: no such file or directory
vet: zerrors_windows_386.go: open zerrors_windows_386.go: no such file or directory
vet: zerrors_windows_amd64.go: open zerrors_windows_amd64.go: no such file or directory
vet: zsyscall_darwin_386.go: open zsyscall_darwin_386.go: no such file or directory
vet: zsyscall_freebsd_386.go: open zsyscall_freebsd_386.go: no such file or directory
vet: zsyscall_freebsd_amd64.go: open zsyscall_freebsd_amd64.go: no such file or directory
vet: zsyscall_freebsd_arm.go: open zsyscall_freebsd_arm.go: no such file or directory
vet: zsyscall_linux_386.go: open zsyscall_linux_386.go: no such file or directory
vet: zsyscall_linux_amd64.go: open zsyscall_linux_amd64.go: no such file or directory
vet: zsyscall_linux_arm.go: open zsyscall_linux_arm.go: no such file or directory
vet: zsyscall_netbsd_386.go: open zsyscall_netbsd_386.go: no such file or directory
vet: zsyscall_netbsd_amd64.go: open zsyscall_netbsd_amd64.go: no such file or directory
vet: zsyscall_openbsd_386.go: open zsyscall_openbsd_386.go: no such file or directory
vet: zsyscall_openbsd_amd64.go: open zsyscall_openbsd_amd64.go: no such file or directory
vet: zsyscall_plan9_386.go: open zsyscall_plan9_386.go: no such file or directory
vet: zsyscall_plan9_amd64.go: open zsyscall_plan9_amd64.go: no such file or directory
vet: zsyscall_windows_386.go: open zsyscall_windows_386.go: no such file or directory
vet: zsyscall_windows_amd64.go: open zsyscall_windows_amd64.go: no such file or directory
vet: zsysctl_openbsd.go: open zsysctl_openbsd.go: no such file or directory
vet: zsysnum_darwin_386.go: open zsysnum_darwin_386.go: no such file or directory
vet: zsysnum_freebsd_386.go: open zsysnum_freebsd_386.go: no such file or directory
vet: zsysnum_freebsd_amd64.go: open zsysnum_freebsd_amd64.go: no such file or directory
vet: zsysnum_freebsd_arm.go: open zsysnum_freebsd_arm.go: no such file or directory
vet: zsysnum_linux_386.go: open zsysnum_linux_386.go: no such file or directory
vet: zsysnum_linux_amd64.go: open zsysnum_linux_amd64.go: no such file or directory
vet: zsysnum_linux_arm.go: open zsysnum_linux_arm.go: no such file or directory
vet: zsysnum_netbsd_386.go: open zsysnum_netbsd_386.go: no such file or directory
vet: zsysnum_netbsd_amd64.go: open zsysnum_netbsd_amd64.go: no such file or directory
vet: zsysnum_openbsd_386.go: open zsysnum_openbsd_386.go: no such file or directory
vet: zsysnum_openbsd_amd64.go: open zsysnum_openbsd_amd64.go: no such file or directory
vet: zsysnum_plan9_386.go: open zsysnum_plan9_386.go: no such file or directory
vet: zsysnum_plan9_amd64.go: open zsysnum_plan9_amd64.go: no such file or directory
vet: zsysnum_windows_386.go: open zsysnum_windows_386.go: no such file or directory
vet: zsysnum_windows_amd64.go: open zsysnum_windows_amd64.go: no such file or directory
vet: ztypes_darwin_386.go: open ztypes_darwin_386.go: no such file or directory
vet: ztypes_freebsd_386.go: open ztypes_freebsd_386.go: no such file or directory
vet: ztypes_freebsd_amd64.go: open ztypes_freebsd_amd64.go: no such file or directory
vet: ztypes_freebsd_arm.go: open ztypes_freebsd_arm.go: no such file or directory
vet: ztypes_linux_386.go: open ztypes_linux_386.go: no such file or directory
vet: ztypes_linux_amd64.go: open ztypes_linux_amd64.go: no such file or directory
vet: ztypes_linux_arm.go: open ztypes_linux_arm.go: no such file or directory
vet: ztypes_netbsd_386.go: open ztypes_netbsd_386.go: no such file or directory
vet: ztypes_netbsd_amd64.go: open ztypes_netbsd_amd64.go: no such file or directory
vet: ztypes_openbsd_386.go: open ztypes_openbsd_386.go: no such file or directory
vet: ztypes_openbsd_amd64.go: open ztypes_openbsd_amd64.go: no such file or directory
vet: ztypes_plan9_386.go: open ztypes_plan9_386.go: no such file or directory
vet: ztypes_plan9_amd64.go: open ztypes_plan9_amd64.go: no such file or directory
vet: ztypes_windows.go: open ztypes_windows.go: no such file or directory
vet: ztypes_windows_386.go: open ztypes_windows_386.go: no such file or directory
vet: ztypes_windows_amd64.go: open ztypes_windows_amd64.go: no such file or directory
exit status 2

It also fails on commands that declare the "documentation" package in the
doc.go file:

% cd $GOROOT/src/cmd
% go vet ./gofmt
vet: doc.go: open doc.go: no such file or directory
exit status 2

Again, if I cd to $GOROOT/src/cmd/gofmt or $GOROOT/src/pkg/syscall and run
"naked" go vet, everything works fine.