cmd/compile: "internal compiler error: NewBulk too big" while running a program with dlv

[sufiyan-techp]

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

$ go version
go version go1.19.2 darwin/amd64

Does this issue reproduce with the latest release?

YES

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

go env Output

$ go env
GO111MODULE="on"
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/sufiyan/Library/Caches/go-build"
GOENV="/Users/sufiyan/Library/Application Support/go/env"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS="-mod=vendor"
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOINSECURE=""
GOMODCACHE="/Users/sufiyan/Workspace/Go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="darwin"
GOPATH="/Users/sufiyan/Workspace/Go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"
GOVCS=""
GOVERSION="go1.19.2"
GCCGO="gccgo"
GOAMD64="v1"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/Users/sufiyan/Workspace/Go/src/github.com/cdktf-poc/go.mod"
GOWORK=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -arch x86_64 -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/cm/lqydsrqj7b3cl_01bqz8048c0000gn/T/go-build1841126309=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

dlv debug main.go

Minimal program:
https://github.com/sufiyan-techp/cdktf-poc

dlv debug main.go

PS: go build/run work successfully.

What did you expect to see?

The program starts in debug mode successfully.

What did you see instead?

github.com/hashicorp/cdktf-provider-aws-go/aws/v9/ec2
<autogenerated>:1: internal compiler error: NewBulk too big: nbit=45718 count=439306 nword=1429 size=627768274

Please file a bug report including a short program that triggers the error.
https://go.dev/issue/new
exit status 2

[randall77]

When I try to load https://github.com/sufiyan-techp/cdktf-poc/tree/main/vendor/github.com/hashicorp/cdktf-provider-aws-go/aws/v9 , I get the warning "Sorry, we had to truncate this directory to 1,000 files. 1,158 entries were omitted from the list.". Similarly with the ec2 subdirectory, even worse with the ec2/ec2.go file, which is 2MB+ and github won't show it.

So, there's some really big stuff in this program. I'm not terribly surprised that we get this error, which is basically saying that the # of variables * # of safe points in a function is more than 2^32. There may be something with -N -l (the compiler flags that dlv passes to the compiler) that push things over the edge, that we might be able to tweak. But I'm skeptical there would be anything ovbious.

A workaround would be to debug an optimized binary, that seems to at least build successfully.

[sufiyan-techp]

@randall77 , thanks for the prompt reply. I am looking into building an optimized binary, do let me know if you have any other insights.

[Jeet007]

@sufiyan-techp @randall77 How would we debug the optimized binary with delve? I am running into same issue while using cdktf go bindings for Datadog provide and this line seems to be the issue: github.com/cdktf/cdktf-provider-datadog-go/datadog/v5/dashboard. This makes it difficult to work with Go.