runtime: crash at startup on darwin_386 with -linkmode=external

[heschi]

On OS X:

$ sw_vers 
ProductName:    Mac OS X
ProductVersion: 10.13.3
BuildVersion:   17D47

A hello world program, built for 386 with CGO_ENABLED=0 and -linkmode=external, crashes at startup with an error in bsdthread_register:

GOARCH=386 CGO_ENABLED=0 go build -ldflags=-linkmode=external src/hello.go && ./hello
# command-line-arguments
loadinternal: cannot find runtime/cgo
fatal error: runtime: bsdthread_register error

runtime stack:
runtime.throw(0x40aa344, 0x21)
        /usr/local/Cellar/go/1.10/libexec/src/runtime/panic.go:619 +0x6b fp=0xbffffb64 sp=0xbffffb58 pc=0x4024ddb
runtime.goenvs()
        /usr/local/Cellar/go/1.10/libexec/src/runtime/os_darwin.go:129 +0x63 fp=0xbffffb78 sp=0xbffffb64 pc=0x4022e43
runtime.schedinit()
        /usr/local/Cellar/go/1.10/libexec/src/runtime/proc.go:496 +0x88 fp=0xbffffba0 sp=0xbffffb78 pc=0x4027258
runtime.rt0_go(0xbffffc48, 0xc, 0x4197306, 0x0, 0x41b898a, 0x51f800bd, 0x4000000, 0xbffffca0, 0xbffffc50, 0xbffffc18, ...)
        /usr/local/Cellar/go/1.10/libexec/src/runtime/asm_386.s:297 +0x224 fp=0xbffffba4 sp=0xbffffba0 pc=0x4046af4

but works fine with CGO_ENABLED=1:

$ GOARCH=386 CGO_ENABLED=1 go build -ldflags=-linkmode=external src/hello.go && ./hello
hi

Note the loadinternal log, which comes from the linker but does not cause a build failure. I don't know if that's related.

This reproduces with every version of Go I've tried. @randall77 says it works fine on OSX 10.11.

cc @aclements since this is pretty old code with no better owner.

[heschi]

Possibly related to #18171, but @andybons reproduced it on a Mac with no antivirus software installed.

[ianlancetaylor]

This is almost certainly fixed by the work done for #17490. Optimistically closing.

[heschi]

Agreed, I think I just forgot to update this. I just rechecked and it's passing now.

[mrajashree]

@ianlancetaylor There are many PRs referencing this issue #18171, I'm not able to find which one will resolve the error loadinternal: cannot find runtime/cgo. I went through the PRs but the PR descriptions didn't indicate the fix for this. Can you please point me to that PR?

[ianlancetaylor]

@mrajashree The work for #17490 was a complete overhaul of how the Go runtime interacts with the Mac OS kernel. There was no single CL that fixed any specific problem. If you are encountering the bsdthread_register error, then I think you will need to upgrade to 1.11 when it is available. If you are not seeing a bsdthread_register error, then you likely have a different problem and should open a new issue with details.

[mrajashree]

@ianlancetaylor okay, thanks for the prompt reply