Use Cmd.CombinedOutput() to get the actual error message

[Ripounet]

Here is the first error I stumbled on after gogetting :

$ godebug run reorder.go
Failed to identify standard library packages. Here's the error from 'go list std':
cmd/addr2line
cmd/cgo
cmd/fix
cmd/go
cmd/gofmt
...200 more lines...

and here is what the true command displays on my system (error on stderr, list items on stdin) :

$ go list std
can't load package: package pkg/runtime: C source files not allowed when not using cgo: atomic_amd64x.c cgocall.c defs.c env_posix.c float.c heapdump.c lock_futex.c mcache.c mcentral.c mem_linux.c mfixalloc.c mgc0.c mheap.c msize.c netpoll_epoll.c os_linux.c panic.c parfor.c print.c proc.c race0.c rune.c runtime.c signal_amd64x.c signal_unix.c stack.c sys_x86.c traceback_x86.c vdso_linux_amd64.c zalg_linux_amd64.c zchan_linux_amd64.c zcomplex_linux_amd64.c zcpuprof_linux_amd64.c zhashmap_linux_amd64.c ziface_linux_amd64.c zlfstack_linux_amd64.c zmalloc_linux_amd64.c zmprof_linux_amd64.c znetpoll_linux_amd64.c zrdebug_linux_amd64.c zruntime1_linux_amd64.c zsema_linux_amd64.c zsigqueue_linux_amd64.c zslice_linux_amd64.c zstring_linux_amd64.c zsymtab_linux_amd64.c ztime_linux_amd64.c
can't load package: package pkg/runtime/debug: C source files not allowed when not using cgo: debug.c
cmd/addr2line
cmd/cgo
cmd/fix
cmd/go
cmd/gofmt
...200 more lines...

[jeremyschlatter]

Thanks! I would like to solve the underlying issue, too. Could you post a copy of reorder.go or a simplified version that shows the same problem?

[Ripounet]

Hi Jeremy The same happens when godebug running a hello world go file. The root of the problem seems to be that for some reason "go list std" prints errors and returns value 1 (though it also prints the non-error packages). Not sure anything can be done in godebug, it's already sensible to print the error and continue execution. Maybe print the error to Stderr instead of Stdout? Cheers

[jeremyschlatter]

I made it print to stderr and cleaned up the message a bit. Thanks for letting me know about this!

I'm guessing godebug should still work in this case, though possibly a bit slower. Is it otherwise working correctly for you?