go: cmd/compile: provide error message for giant strings instead of crashing

Please answer these questions before submitting your issue. Thanks!

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

go version devel +fca9fc5 Thu Jun 16 19:45:33 2016 +0000 darwin/amd64

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

$ go env GOARCH=“amd64” GOBIN=“” GOEXE=“” GOHOSTARCH=“amd64” GOHOSTOS=“darwin” GOOS=“darwin” GOPATH=“/Users/bmizerany” GORACE=“” GOROOT=“/usr/local/go” GOTOOLDIR=“/usr/local/go/pkg/tool/darwin_amd64” CC=“clang” GOGCCFLAGS=“-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/dx/jcs03lw901vc05cjjqyjf8y00000gn/T/go-build243723307=/tmp/go-build -gno-record-gcc-switches -fno-common” CXX=“clang++” CGO_ENABLED=“1”

1. What did you do?

I generated this file (165mb) and ran go build:

https://drive.google.com/open?id=0BwlBkts6X4NueEgzUVZiLUJwYms

1. What did you expect to see?

A successful build.

1. What did you see instead?

This

$ go build table.go 
# command-line-arguments
runtime: goroutine stack exceeds 1000000000-byte limit
fatal error: stack overflow

runtime stack:
runtime.throw(0x4f62ab, 0xe)
    /usr/local/go/src/runtime/panic.go:566 +0x95
runtime.newstack()
    /usr/local/go/src/runtime/stack.go:1054 +0x416
runtime.morestack()
    /usr/local/go/src/runtime/asm_amd64.s:366 +0x7f

goroutine 1 [running]:
runtime.heapBitsSetType(0xc436720e10, 0x90, 0x90, 0x4e77c0)
    /usr/local/go/src/runtime/mbitmap.go:867 fp=0xc4912b0260 sp=0xc4912b0258
runtime.mallocgc(0x90, 0x4e77c0, 0xfe01, 0xc436720d80)
    /usr/local/go/src/runtime/malloc.go:690 +0x5ae fp=0xc4912b0300 sp=0xc4912b0260
runtime.newobject(0x4e77c0, 0x0)
    /usr/local/go/src/runtime/malloc.go:785 +0x38 fp=0xc4912b0330 sp=0xc4912b0300
cmd/compile/internal/gc.treecopy(0xc422f31cb0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:495 +0x4ae fp=0xc4912b03e8 sp=0xc4912b0330
cmd/compile/internal/gc.treecopy(0xc422f31dd0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b04a0 sp=0xc4912b03e8
cmd/compile/internal/gc.treecopy(0xc422f31ef0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0558 sp=0xc4912b04a0
cmd/compile/internal/gc.treecopy(0xc422f32090, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0610 sp=0xc4912b0558
cmd/compile/internal/gc.treecopy(0xc422f321b0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b06c8 sp=0xc4912b0610
cmd/compile/internal/gc.treecopy(0xc422f322d0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0780 sp=0xc4912b06c8
cmd/compile/internal/gc.treecopy(0xc422f323f0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0838 sp=0xc4912b0780
cmd/compile/internal/gc.treecopy(0xc422f32510, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b08f0 sp=0xc4912b0838
cmd/compile/internal/gc.treecopy(0xc422f32630, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b09a8 sp=0xc4912b08f0
cmd/compile/internal/gc.treecopy(0xc422f32750, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0a60 sp=0xc4912b09a8
cmd/compile/internal/gc.treecopy(0xc422f32870, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0b18 sp=0xc4912b0a60
cmd/compile/internal/gc.treecopy(0xc422f32990, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0bd0 sp=0xc4912b0b18
cmd/compile/internal/gc.treecopy(0xc422f32ab0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0c88 sp=0xc4912b0bd0
cmd/compile/internal/gc.treecopy(0xc422f32bd0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0d40 sp=0xc4912b0c88
cmd/compile/internal/gc.treecopy(0xc422f32cf0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0df8 sp=0xc4912b0d40
cmd/compile/internal/gc.treecopy(0xc422f32e10, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0eb0 sp=0xc4912b0df8
cmd/compile/internal/gc.treecopy(0xc422f32f30, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b0f68 sp=0xc4912b0eb0
cmd/compile/internal/gc.treecopy(0xc422f33050, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1020 sp=0xc4912b0f68
cmd/compile/internal/gc.treecopy(0xc422f33170, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b10d8 sp=0xc4912b1020
cmd/compile/internal/gc.treecopy(0xc422f33290, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1190 sp=0xc4912b10d8
cmd/compile/internal/gc.treecopy(0xc422f333b0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1248 sp=0xc4912b1190
cmd/compile/internal/gc.treecopy(0xc422f334d0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1300 sp=0xc4912b1248
cmd/compile/internal/gc.treecopy(0xc422f335f0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b13b8 sp=0xc4912b1300
cmd/compile/internal/gc.treecopy(0xc422f33710, 0xc400000000, 0x1000000000000)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1470 sp=0xc4912b13b8
cmd/compile/internal/gc.treecopy(0xc422f33830, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1528 sp=0xc4912b1470
cmd/compile/internal/gc.treecopy(0xc422f33950, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b15e0 sp=0xc4912b1528
cmd/compile/internal/gc.treecopy(0xc422f33a70, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1698 sp=0xc4912b15e0
cmd/compile/internal/gc.treecopy(0xc422f33b90, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1750 sp=0xc4912b1698
cmd/compile/internal/gc.treecopy(0xc422f33cb0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1808 sp=0xc4912b1750
cmd/compile/internal/gc.treecopy(0xc422f33dd0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b18c0 sp=0xc4912b1808
cmd/compile/internal/gc.treecopy(0xc422f33ef0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1978 sp=0xc4912b18c0
cmd/compile/internal/gc.treecopy(0xc422f38090, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1a30 sp=0xc4912b1978
cmd/compile/internal/gc.treecopy(0xc422f381b0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1ae8 sp=0xc4912b1a30
cmd/compile/internal/gc.treecopy(0xc422f382d0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1ba0 sp=0xc4912b1ae8
cmd/compile/internal/gc.treecopy(0xc422f383f0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1c58 sp=0xc4912b1ba0
cmd/compile/internal/gc.treecopy(0xc422f38510, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1d10 sp=0xc4912b1c58
cmd/compile/internal/gc.treecopy(0xc422f38630, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1dc8 sp=0xc4912b1d10
cmd/compile/internal/gc.treecopy(0xc422f38750, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1e80 sp=0xc4912b1dc8
cmd/compile/internal/gc.treecopy(0xc422f38870, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1f38 sp=0xc4912b1e80
cmd/compile/internal/gc.treecopy(0xc422f38990, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b1ff0 sp=0xc4912b1f38
cmd/compile/internal/gc.treecopy(0xc422f38ab0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b20a8 sp=0xc4912b1ff0
cmd/compile/internal/gc.treecopy(0xc422f38bd0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2160 sp=0xc4912b20a8
cmd/compile/internal/gc.treecopy(0xc422f38cf0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2218 sp=0xc4912b2160
cmd/compile/internal/gc.treecopy(0xc422f38e10, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b22d0 sp=0xc4912b2218
cmd/compile/internal/gc.treecopy(0xc422f38f30, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2388 sp=0xc4912b22d0
cmd/compile/internal/gc.treecopy(0xc422f39050, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2440 sp=0xc4912b2388
cmd/compile/internal/gc.treecopy(0xc422f39170, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b24f8 sp=0xc4912b2440
cmd/compile/internal/gc.treecopy(0xc422f39290, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b25b0 sp=0xc4912b24f8
cmd/compile/internal/gc.treecopy(0xc422f393b0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2668 sp=0xc4912b25b0
cmd/compile/internal/gc.treecopy(0xc422f394d0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2720 sp=0xc4912b2668
cmd/compile/internal/gc.treecopy(0xc422f395f0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b27d8 sp=0xc4912b2720
cmd/compile/internal/gc.treecopy(0xc422f39710, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2890 sp=0xc4912b27d8
cmd/compile/internal/gc.treecopy(0xc422f39830, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2948 sp=0xc4912b2890
cmd/compile/internal/gc.treecopy(0xc422f39950, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2a00 sp=0xc4912b2948
cmd/compile/internal/gc.treecopy(0xc422f39a70, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2ab8 sp=0xc4912b2a00
cmd/compile/internal/gc.treecopy(0xc422f39b90, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2b70 sp=0xc4912b2ab8
cmd/compile/internal/gc.treecopy(0xc422f39cb0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2c28 sp=0xc4912b2b70
cmd/compile/internal/gc.treecopy(0xc422f39dd0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2ce0 sp=0xc4912b2c28
cmd/compile/internal/gc.treecopy(0xc422f39ef0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2d98 sp=0xc4912b2ce0
cmd/compile/internal/gc.treecopy(0xc422f3c090, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2e50 sp=0xc4912b2d98
cmd/compile/internal/gc.treecopy(0xc422f3c1b0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2f08 sp=0xc4912b2e50
cmd/compile/internal/gc.treecopy(0xc422f3c2d0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b2fc0 sp=0xc4912b2f08
cmd/compile/internal/gc.treecopy(0xc422f3c3f0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3078 sp=0xc4912b2fc0
cmd/compile/internal/gc.treecopy(0xc422f3c510, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3130 sp=0xc4912b3078
cmd/compile/internal/gc.treecopy(0xc422f3c630, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b31e8 sp=0xc4912b3130
cmd/compile/internal/gc.treecopy(0xc422f3c750, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b32a0 sp=0xc4912b31e8
cmd/compile/internal/gc.treecopy(0xc422f3c870, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3358 sp=0xc4912b32a0
cmd/compile/internal/gc.treecopy(0xc422f3c990, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3410 sp=0xc4912b3358
cmd/compile/internal/gc.treecopy(0xc422f3cab0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b34c8 sp=0xc4912b3410
cmd/compile/internal/gc.treecopy(0xc422f3cbd0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3580 sp=0xc4912b34c8
cmd/compile/internal/gc.treecopy(0xc422f3ccf0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3638 sp=0xc4912b3580
cmd/compile/internal/gc.treecopy(0xc422f3ce10, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b36f0 sp=0xc4912b3638
cmd/compile/internal/gc.treecopy(0xc422f3cf30, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b37a8 sp=0xc4912b36f0
cmd/compile/internal/gc.treecopy(0xc422f3d050, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3860 sp=0xc4912b37a8
cmd/compile/internal/gc.treecopy(0xc422f3d170, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3918 sp=0xc4912b3860
cmd/compile/internal/gc.treecopy(0xc422f3d290, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b39d0 sp=0xc4912b3918
cmd/compile/internal/gc.treecopy(0xc422f3d3b0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3a88 sp=0xc4912b39d0
cmd/compile/internal/gc.treecopy(0xc422f3d4d0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3b40 sp=0xc4912b3a88
cmd/compile/internal/gc.treecopy(0xc422f3d5f0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3bf8 sp=0xc4912b3b40
cmd/compile/internal/gc.treecopy(0xc422f3d710, 0xc400000000, 0x1000000000000)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3cb0 sp=0xc4912b3bf8
cmd/compile/internal/gc.treecopy(0xc422f3d830, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3d68 sp=0xc4912b3cb0
cmd/compile/internal/gc.treecopy(0xc422f3d950, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3e20 sp=0xc4912b3d68
cmd/compile/internal/gc.treecopy(0xc422f3da70, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3ed8 sp=0xc4912b3e20
cmd/compile/internal/gc.treecopy(0xc422f3db90, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b3f90 sp=0xc4912b3ed8
cmd/compile/internal/gc.treecopy(0xc422f3dcb0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b4048 sp=0xc4912b3f90
cmd/compile/internal/gc.treecopy(0xc422f3ddd0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b4100 sp=0xc4912b4048
cmd/compile/internal/gc.treecopy(0xc422f3def0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b41b8 sp=0xc4912b4100
cmd/compile/internal/gc.treecopy(0xc422f3e090, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b4270 sp=0xc4912b41b8
cmd/compile/internal/gc.treecopy(0xc422f3e1b0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b4328 sp=0xc4912b4270
cmd/compile/internal/gc.treecopy(0xc422f3e2d0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b43e0 sp=0xc4912b4328
cmd/compile/internal/gc.treecopy(0xc422f3e3f0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b4498 sp=0xc4912b43e0
cmd/compile/internal/gc.treecopy(0xc422f3e510, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b4550 sp=0xc4912b4498
cmd/compile/internal/gc.treecopy(0xc422f3e630, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b4608 sp=0xc4912b4550
cmd/compile/internal/gc.treecopy(0xc422f3e750, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b46c0 sp=0xc4912b4608
cmd/compile/internal/gc.treecopy(0xc422f3e870, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b4778 sp=0xc4912b46c0
cmd/compile/internal/gc.treecopy(0xc422f3e990, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b4830 sp=0xc4912b4778
cmd/compile/internal/gc.treecopy(0xc422f3eab0, 0xc400000000, 0x0)
    /usr/local/go/src/cmd/compile/internal/gc/subr.go:497 +0x523 fp=0xc4912b48e8 sp=0xc4912b4830
...additional frames elided...