cmd/pprof: panics if profile is not found

[rhysh]

Go version

go version devel go1.23-019353d532 Thu May 23 18:51:17 2024 +0000 linux/amd64

Output of go env in your module/workspace:

GO111MODULE=''
GOARCH='amd64'
GOBIN=''
GOCACHE='/home/rhysh/.cache/go-build'
GOENV='/home/rhysh/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMODCACHE='/home/rhysh/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/home/rhysh/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/home/rhysh/sdk/go-dev'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/home/rhysh/sdk/go-dev/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='devel go1.23-019353d532 Thu May 23 18:51:17 2024 +0000'
GODEBUG=''
GOTELEMETRY='local'
GOTELEMETRYDIR='/home/rhysh/.config/go/telemetry'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'
GOMOD='/dev/null'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build3616585202=/tmp/go-build -gno-record-gcc-switches'

What did you do?

$ ./bin/go tool pprof ./missing

What did you see happen?

$ ./bin/go tool pprof ./missing
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x91c737]

goroutine 17 [running]:
cmd/vendor/github.com/google/pprof/internal/driver.fetch({0x7fff1e6ef510, 0x9}, 0xffffffffc4653600, 0xffffffffc4653600, {0x7ff5e88cb1f8, 0xc000080238}, {0xb2eca0, 0xc00009e8a0})
	/home/rhysh/sdk/go-dev/src/cmd/vendor/github.com/google/pprof/internal/driver/fetch.go:514 +0x2f7
cmd/vendor/github.com/google/pprof/internal/driver.grabProfile(0xc0001ec960, {0x7fff1e6ef510?, 0x9?}, {0x7ff5e88cb1d8?, 0xf1e060?}, {0xb2fc68, 0xc0000331d0}, {0x7ff5e88cb1f8, 0xc000080238}, {0xb2eca0, ...})
	/home/rhysh/sdk/go-dev/src/cmd/vendor/github.com/google/pprof/internal/driver/fetch.go:334 +0x131
cmd/vendor/github.com/google/pprof/internal/driver.concurrentGrab.func1(0xc000209000)
	/home/rhysh/sdk/go-dev/src/cmd/vendor/github.com/google/pprof/internal/driver/fetch.go:211 +0x86
created by cmd/vendor/github.com/google/pprof/internal/driver.concurrentGrab in goroutine 7
	/home/rhysh/sdk/go-dev/src/cmd/vendor/github.com/google/pprof/internal/driver/fetch.go:209 +0x8f

What did you expect to see?

$ ./bin/go tool pprof ./missing
./missing: open ./missing: no such file or directory
failed to fetch any source profiles

Go 1.22 works.

Bisect of this repo says "63dd79c07b0026b58f421a5273c41e705ccb73d1 is the first bad commit". I haven't bisected github.com/google/pprof.

[prattmic]

google/pprof@a5a03c7 looks like it would cause this.

@dmitshur when do we typically update the vendored version of pprof? If we haven't done so yet, the best bet is probably an upstream fix and then update from upstream.

[rhysh]

Upstream is still broken, and yes a bisect there points to google/pprof@a5a03c7

[dmitshur]

@prattmic We will update it soon, now that we've entered the release freeze, as part of #36905. It's also fine to update it separately for this as needed.

[odeke-em]

I've mailed out a fix for the google/pprof library per PR google/pprof#865.

[cuishuang]

The upstream has been updated (google/pprof#864). Thanks for the corresponding update.

This issue was caused by my modifications to solve the colon issue with pprof on Windows, including upstream pprof and Go.

Apologies for any inconvenience caused.

[gopherbot]

Change https://go.dev/cl/588655 mentions this issue: cmd/vendor: update github.com/google/pprof