cmd/link: unexpected fault address 0x7fa5b6698538

[BenLubar]

What version of Go are you using (go version)?

$ go version
go version go1.13.8 linux/amd64

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GO111MODULE=""
GOARCH="amd64"
GOBIN="/home/ben/go/bin"
GOCACHE="/home/ben/.cache/go-build"
GOENV="/home/ben/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/ben/.golang-path"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/lib/go-1.13"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/lib/go-1.13/pkg/tool/linux_amd64"
GCCGO="gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/ben/src/tolpaha/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build334490834=/tmp/go-build -gno-record-gcc-switches"
GOROOT/bin/go version: go version go1.13.8 linux/amd64
GOROOT/bin/go tool compile -V: compile version go1.13.8
uname -sr: Linux 5.4.0-33-generic
Distributor ID: Ubuntu
Description:    Ubuntu 20.04 LTS
Release:        20.04
Codename:       focal
/lib/x86_64-linux-gnu/libc.so.6: GNU C Library (Ubuntu GLIBC 2.31-0ubuntu9) stable release version 2.31.
gdb --version: GNU gdb (Ubuntu 9.1-0ubuntu1) 9.1

What did you do?

entr -s 'go run .'

It doesn't seem to depend on the code. touching a file can make it happen or not happen.

Here's an example of the code it happened with: https://git.lubar.me/ben/tolpaha/src/commit/ac4aab9f17e1de34424a8836964c1deee659aff1

What did you expect to see?

Program compiles and runs

What did you see instead?

unexpected fault address 0x7fa5b6698538
fatal error: fault
[signal SIGBUS: bus error code=0x2 addr=0x7fa5b6698538 pc=0x4d8aed]

goroutine 1 [running]:
runtime.throw(0x690f28, 0x5)
        /usr/lib/go-1.13/src/runtime/panic.go:774 +0x72 fp=0xc000752fa8 sp=0xc000752f78 pc=0x42dc32
runtime.sigpanic()
        /usr/lib/go-1.13/src/runtime/signal_unix.go:391 +0x455 fp=0xc000752fd8 sp=0xc000752fa8 pc=0x442bd5
encoding/binary.littleEndian.PutUint64(...)
        /usr/lib/go-1.13/src/encoding/binary/binary.go:90
encoding/binary.(*littleEndian).PutUint64(0x8777c0, 0x7fa5b6698538, 0x30, 0x4a9ac8, 0xd423e0)
        <autogenerated>:1 +0x3d fp=0xc000752ff8 sp=0xc000752fd8 pc=0x4d8aed
cmd/link/internal/ld.relocsym(0xc0006e6000, 0xc00491c570)
        /usr/lib/go-1.13/src/cmd/link/internal/ld/data.go:556 +0xae0 fp=0xc000753258 sp=0xc000752ff8 pc=0x554f30
cmd/link/internal/ld.(*Link).reloc(0xc0006e6000)
        /usr/lib/go-1.13/src/cmd/link/internal/ld/data.go:570 +0xb4 fp=0xc0007532d0 sp=0xc000753258 pc=0x557c54
cmd/link/internal/ld.Main(0x84cdc0, 0x10, 0x20, 0x1, 0x7, 0x10, 0x69ac6f, 0x1b, 0x697756, 0x14, ...)
        /usr/lib/go-1.13/src/cmd/link/internal/ld/main.go:263 +0xd6e fp=0xc000753428 sp=0xc0007532d0 pc=0x5ab5ae
main.main()
        /usr/lib/go-1.13/src/cmd/link/main.go:65 +0x1d6 fp=0xc000753f60 sp=0xc000753428 pc=0x614606
runtime.main()
        /usr/lib/go-1.13/src/runtime/proc.go:203 +0x21e fp=0xc000753fe0 sp=0xc000753f60 pc=0x42f5ce
runtime.goexit()
        /usr/lib/go-1.13/src/runtime/asm_amd64.s:1357 +0x1 fp=0xc000753fe8 sp=0xc000753fe0 pc=0x45a501

[ianlancetaylor]

The linker has changed quite a lot. Is there a way that you could test this against the master branch? Thanks.

[jeremyfaller]

I tried with the dev.link branch, and OP's github branch. It failed to compile for other reasons, but if it's too not too much to update the link to a working piece of code I'd be happy to take a look there as well.

[BenLubar]

To make it compile, you just need to go generate ./assets

I'm omitting the generated file for now to avoid a lot of source control churn.

I noticed my SSD was almost full, so this may be related to that rather than anything in Go.

[cherrymui]

I noticed my SSD was almost full

Probably related to #37310. It should be fixed on tip (Go 1.15 to be).

[BenLubar]

Hasn't happened again, so closing as a duplicate of #37310