Doesn't work at all in Ubuntu 14.04 x64 about delve

[derekparker]

Hmmm... What kind of app is it? What happens when you run it by itself,
does it panic?

You say the process isn't running, what does ps have to say about your
process while Delve is running?

I'm wondering if your program is crashing and a signal is occurring that
delve is ignoring, causing your app to die and delve to block in a wait
call while waiting for a breakpoint trap.

If it's not too much trouble could you try straceing delve and see if
it's hanging out at a wait call? Or if your code is open source maybe I
can try delve against it and see what's going on.

On Friday, February 13, 2015, Tzvetan Mikov [email protected]
wrote:

I downloaded Go 1.4.1 and built my test app - it worked. Then I did
go get github.com/derekparker/delve/cmd/dlv
dlv path/to/my/app
continue

It prints "new thread spawned 11399" and hangs. ^C doesn't work. The app
isn't running.

I tried setting breakpoints, etc, but it always hangs after the first
"continue".

—
Reply to this email directly or view it on GitHub
https://github.com/derekparker/delve/issues/67.

[derekparker]

@tmikov any update on this?

[tmikov]

Yes, sorry. The app is "hello world", but it hardly matters because it never even reaches "main". It locks up as soon as I do "continue" in the very beginning then and I need to kill "dlv" from a different terminal. I will run "strace" and post as soon as I have something.

[tmikov]

Some more information after testing. The main() routine contains just "fmt.Printf(hello world)" and it never executes. However there is some static variable initialization of logging, etc, If I compile a truly trivial app printing "Hello world", "dlv" does work. So, I suspect that the logging is causing the problem here. I am using "https://github.com/op/go-logging" .

I should note that the app itself does work and I can debug it with "gdb".

Unfortunately it is not open source, but I might be able to narrow it down to an example illustrating the problem.

I ran an "strace" and it is inclear. There are 5 threads. One is blocked in "select(0, NULL, NULL, NULL, {0, 10000}", three are blocked in "futex(..., FUTEX_WAIT, 0, NULL"

[derekparker]

@tmikov thanks for looking into it more. If you could post a gist of a small program that reproduces the failure I'll look into this issue further - could be related to #41. I was just able to reproduce a bug that's causing Delve to hang.

[derekparker]

Alright, I know where we're hanging just not sure why. I'll start looking into a fix for this.

[derekparker]

@tmikov figured out what's wrong - now to fix it. Thank you very much for your help and for reporting this.

[derekparker]

Closing in favor of #70.

[tmikov]

This doesn't seem like an easy fix :-(
Do you still need me to prepare a sample reproducing the problem?

[derekparker]

Yeah it's tough, I have some ideas for how to get around this for the time being though.

No need for a small sample, thank you though.