Join GitHub today
GitHub is home to over 50 million developers working together to host and review code, manage projects, and build software together.
Sign upruntime: load two go so/DLLs in one c++ executable on Windows #36628
Comments
ianlancetaylor
changed the title
|
As far as I know this should be possible, but I'm not at all surprised that it does not work. Can you give us a standalone test case that demonstrates the problem? Thanks. |
|
Thanks for replying!
Every go DLL ships with a golang runtime, I'm curious how they work together? Is there any way to strip away one of them?
I don't know if a simple test case can reproduce this problem. In golang side, it involves net, channel, goroutine, protobuf, log, encoding/json, etc. And golang/c++ have two-way communications(c++ calls golang, golang calls c++ too). Any of these can go wrong. I don't even know how to trigger the crash, quite random. But I will try. |
|
On Unix systems, we use symbol visibility so that although each shared object has a copy of the Go runtime, the two runtimes are independent. In effect you get two entirely different Go worlds. I don't know how that kind of symbol visibility works on Windows. |
|
Got it. I think windows has the equivalent concept, just working in the opposite way. If you don't explicitly export symbols, they are confined in your own mem space. So you are right, it should work here. Looks like I have to dig more information before blaming it on the go part. |
|
After weeks of debugging, we have finally found the bug, it is not related to coexisting of two golang libraries. Multiple golang dlls can work properly even on Windows. |
|
Thanks for following up. |
What version of Go are you using (
go version)?Does this issue reproduce with the latest release?
not sure
What operating system and processor architecture are you using (
go env)?Windows 10 1903
CentOS 7.2
What did you do?
I wrote two different components in golang and compiled them into C dynamic libraries.
Then built a c++ executable with these two dynamic libraries.
Both these libraries have a running goroutine receiving msg from net and call back c++ functions(not the same one though) to notify events.
In the test environment with a light workload, everything works all right.
But when it comes to heavy load production env, it crashes randomly!
Sometimes I can get exception infomation from stderr saying runtime: unknown pc ,
other times it just simply crashes.
I've carefully checked c++ layer and didn't see any suspicious part (c++ layer is quite simple).
And I also notice that windows is more vulnerable. Rarely see it crashes on Linux.
So I wonder if the problem is coming from the go part.
Can two go shared libraries really coexist together in one process???
If not, How can I solve this?? I don't wanna rewrite everything!
What did you expect to see?
Running normally.
What did you see instead?
randomly crashes
sometimes get exception report like following one.
Exception 0xc0000005 0x0 0x0 0x1d1c26b2 PC=0x1d1c26b2 runtime: unknown pc 0x1d1c26b2 stack: frame={sp:0x791f300, fp:0x0} stack=[0x0,0x791f970) 000000000791f200: 0000000077263128 0000000000000000 000000000791f210: 0000000000000010 0000000000440000 000000000791f220: 000000000791f660 0000000000000008 000000000791f230: 0000000000000000 0000000000000000 000000000791f240: 0000000000000000 000000001d1c24fb 000000000791f250: 0000000000000006 0000000000000001 000000000791f260: 0000000000000030 0000000000000001 000000000791f270: 0000000000000000 000007fed5d61be6 000000000791f280: 00000000094ed420 000000001d1c0f3c 000000000791f290: 0000000000000006 000007fed5d61be0 000000000791f2a0: 0000000000000000 0000000000398b60 000000000791f2b0: 000000000791f330 000007fef7585935 000000000791f2c0: 000000000791f330 000000000791f4b0 000000000791f2d0: 0000000000000001 0000000000000010 000000000791f2e0: 0000000000000004 0000000000000001 000000000791f2f0: 0000000000000000 00000000094ed450 000000000791f300: <0000007f00000001 0000000000000006 000000000791f310: 0000000000000006 0000000000000006 000000000791f320: 0000000000000000 0000000000398b80 000000000791f330: 0000000002f3a570 000000001d1dbe96 000000000791f340: 00000000088cbd12 0000000000000000 000000000791f350: 0000000000000001 0000000000000000 000000000791f360: 000000000791f3d8 000007fed5d50ddf 000000000791f370: 00000000094ed420 000000000791f4b0 000000000791f380: 0000000002bebc10 0000000000000000 000000000791f390: fffffffffffffffe 0000000002bebc10 000000000791f3a0: 000000000791f660 000007fed5d45ccc 000000000791f3b0: 000007fed5d61be6 00000000094ed420 000000000791f3c0: 00000000094ed450 0000000000000037 000000000791f3d0: 0000000000000001 00000000094e6828 000000000791f3e0: 00000000094ed420 0000000002bebc10 000000000791f3f0: 00000000094ed420 0000000000000000 runtime: unknown pc 0x1d1c26b2 stack: frame={sp:0x791f300, fp:0x0} stack=[0x0,0x791f970) 000000000791f200: 0000000077263128 0000000000000000 000000000791f210: 0000000000000010 0000000000440000 000000000791f220: 000000000791f660 0000000000000008 000000000791f230: 0000000000000000 0000000000000000 000000000791f240: 0000000000000000 000000001d1c24fb 000000000791f250: 0000000000000006 0000000000000001 000000000791f260: 0000000000000030 0000000000000001 000000000791f270: 0000000000000000 000007fed5d61be6 000000000791f280: 00000000094ed420 000000001d1c0f3c 000000000791f290: 0000000000000006 000007fed5d61be0 000000000791f2a0: 0000000000000000 0000000000398b60 000000000791f2b0: 000000000791f330 000007fef7585935 000000000791f2c0: 000000000791f330 000000000791f4b0 000000000791f2d0: 0000000000000001 0000000000000010 000000000791f2e0: 0000000000000004 0000000000000001 000000000791f2f0: 0000000000000000 00000000094ed450 000000000791f300: <0000007f00000001 0000000000000006 000000000791f310: 0000000000000006 0000000000000006 000000000791f320: 0000000000000000 0000000000398b80 000000000791f330: 0000000002f3a570 000000001d1dbe96 000000000791f340: 00000000088cbd12 0000000000000000 000000000791f350: 0000000000000001 0000000000000000 000000000791f360: 000000000791f3d8 000007fed5d50ddf 000000000791f370: 00000000094ed420 000000000791f4b0 000000000791f380: 0000000002bebc10 0000000000000000 000000000791f390: fffffffffffffffe 0000000002bebc10 000000000791f3a0: 000000000791f660 000007fed5d45ccc 000000000791f3b0: 000007fed5d61be6 00000000094ed420 000000000791f3c0: 00000000094ed450 0000000000000037 000000000791f3d0: 0000000000000001 00000000094e6828 000000000791f3e0: 00000000094ed420 0000000002bebc10 000000000791f3f0: 00000000094ed420 0000000000000000 goroutine 54 [syscall]: main._Cfunc_OnRspOrderInsert(0x88cbd12, 0x398b60, 0x398b80, 0xee000, 0xee000, 0x2, 0x402c8f5c28f5c28f, 0x401828f500000064) _cgo_gotypes.go:78 +0x4c main.RecvRun() D:/workspace_go/src/ccfinvest/libitg/main.go:232 +0xeff created by main.LibITG_ReqUserLogin D:/workspace_go/src/ccfinvest/libitg/main.go:299 +0x53a goroutine 51 [IO wait]: internal/poll.runtime_pollWait(0x38b9198, 0x72, 0x6d553a20) C:/Go/src/runtime/netpoll.go:182 +0x5d internal/poll.(*pollDesc).wait(0xc00010c1c8, 0x72, 0x6d483100, 0x0, 0x0) C:/Go/src/internal/poll/fd_poll_runtime.go:87 +0xa2 internal/poll.(*ioSrv).ExecIO(0x6d6931b0, 0xc00010c018, 0x6d51ed30, 0x2, 0xc00051a2d0, 0x9) C:/Go/src/internal/poll/fd_windows.go:228 +0x124 internal/poll.(*FD).Read(0xc00010c000, 0xc00051a548, 0x4, 0x4, 0x0, 0x0, 0x0) C:/Go/src/internal/poll/fd_windows.go:502 +0x26b net.(*netFD).Read(0xc00010c000, 0xc00051a548, 0x4, 0x4, 0x10000c00008df78, 0x0, 0x4) C:/Go/src/net/fd_windows.go:152 +0x56 net.(*conn).Read(0xc00009c098, 0xc00051a548, 0x4, 0x4, 0x0, 0x0, 0x0) C:/Go/src/net/net.go:177 +0x70 ccfinvest/libitg/itg._recvUntilFull(0x6d5573c0, 0xc00009c098, 0xc00051a548, 0x4, 0x4, 0xc0001d9e00, 0x0) D:/workspace_go/src/ccfinvest/libitg/itg/itg.go:271 +0xc0 ccfinvest/libitg/itg.(*Itg).recvUntilFull(...) D:/workspace_go/src/ccfinvest/libitg/itg/itg.go:288 ccfinvest/libitg/itg.(*Itg).recvRun(0xc0000b83f0) D:/workspace_go/src/ccfinvest/libitg/itg/itg.go:294 +0xaf created by ccfinvest/libitg/itg.(*Itg).Start D:/workspace_go/src/ccfinvest/libitg/itg/itg.go:97 +0x1db goroutine 21 [select]: github.com/globalsign/mgo.newcoarseTimeProvider.func1(0x17d7840, 0xc000086a50) D:/workspace_go/src/github.com/globalsign/mgo/coarse_time.go:51 +0x130 created by github.com/globalsign/mgo.newcoarseTimeProvider D:/workspace_go/src/github.com/globalsign/mgo/coarse_time.go:48 +0x109 goroutine 52 [chan receive]: ccfinvest/libitg/itg.(*Itg).sendRun(0xc0000b83f0) D:/workspace_go/src/ccfinvest/libitg/itg/itg.go:350 +0x4d created by ccfinvest/libitg/itg.(*Itg).Start D:/workspace_go/src/ccfinvest/libitg/itg/itg.go:98 +0x200 goroutine 53 [sleep]: runtime.goparkunlock(...) C:/Go/src/runtime/proc.go:307 time.Sleep(0x6fc23ac00) C:/Go/src/runtime/time.go:105 +0x16e ccfinvest/libitg/itg.(*Itg).keepAliveRun(0xc0000b83f0) D:/workspace_go/src/ccfinvest/libitg/itg/itg.go:380 +0x61 created by ccfinvest/libitg/itg.(*Itg).Start D:/workspace_go/src/ccfinvest/libitg/itg/itg.go:99 +0x225 rax 0x1d4897c0 rbx 0x1c rcx 0x94e1000 rdi 0x0 rsi 0x3 rbp 0x1 rsp 0x791f300 r8 0x1d4897e0 r9 0x1c r10 0x6 r11 0x7f r12 0x2f3a570 r13 0x0 r14 0x1d4897f0 r15 0x0 rip 0x1d1c26b2 rflags 0x10203 cs 0x33 fs 0x53 gs 0x2b