runtime/pprof: CPU profiling crashes on NetBSD

[rillig]

• go version go1.5.2 netbsd/amd64
• NetBSD 7.0 amd64

The following program crashes after less than a second.

package main

import (
        "os"
        "runtime/pprof"
)

func main() {
        f, _ := os.Create("demo.pprof")
        pprof.StartCPUProfile(f)
        for {
        }
}

The crash only happens in profiling mode.

When run under the eyes of ktruss -t A -R, the program does this:

thread | relative time | syscall
...
2   0.000011454   __nanosleep50   = 0
2   0.000035199   __clock_gettime50(0, 0xc820037ee8) = 0
2   0.000033803   __clock_gettime50(0, 0xc820037ed0) = 0
3   -1.979777508  stop kernel
3   0.020298198   resume kernel
3   0.000010895   compat_60__lwp_park Err#4 EINTR
3   0.000015364   SIGPROF caught handler=0x455aa0 mask=0x0 code=0x0
3   0.000084925   setcontext(0x40) Err#14 EFAULT
3   0.000009499   exit(0xffffffffffffffff)
2   -1.999839927  stop kernel
2   0.000196948   resume kernel
2   0.000006984   __nanosleep50   Err#4 EINTR
3   -1.999966198  stop kernel
3   0.000063973   resume kernel
3   0.000009777   stop kernel
3   0.000053079   resume kernel

[bradfitz]

Can you try this with master? (which is soon to become Go 1.6) The Go 1.5.x. tree is frozen except for critical problems and security things, and this is neither.

[rillig]

I tried to reproduce this issue using master 66a7097, but building the master failed, as detailed in #13945.

[rillig]

Now that #13945 is fixed, I tried again with master 7d8c8c0, and it works perfectly.

[bradfitz]

Great! Closing this, then.