x/tools/go/ssa: emitConv panic on generics #57272

zpavlinovic · 2022-12-13T00:17:56Z

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

$ go version

go1.19.3

Does this issue reproduce with the latest release?

Yes, also reproduced with go version go1.20-pre3.

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

go env Output

$ go env
GO111MODULE=""

GOARCH="amd64"

GOBIN=""

GOCACHE="[redacted]/.cache/go-build"

GOENV="[redacted]/.config/go/env"

GOEXE=""

GOEXPERIMENT=""

GOFLAGS=""

GOHOSTARCH="amd64"

GOHOSTOS="linux"

GOINSECURE=""

GOMODCACHE="[redacted]/go/pkg/mod"

GONOPROXY=".git.corp.google.com"

GONOSUMDB=".git.corp.google.com"

GOOS="linux"

GOPATH="[redacted]/go"

GOPRIVATE="*.git.corp.google.com"

GOPROXY="https://proxy.golang.org,direct"

GOROOT="[redacted]"

GOSUMDB="sum.golang.org"

GOTMPDIR=""

GOTOOLDIR="[redacted]/linux_amd64"

GOVCS=""

GOVERSION="go1.20-pre3 cl/474093167 +a813be86df"

GCCGO="gccgo"

GOAMD64="v1"

AR="ar"

CC="clang"

CXX="clang++"

CGO_ENABLED="1"

GOMOD="[redacted]/minio/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 -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -Wl,--no-gc-sections -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build2425109656=/tmp/go-build -gno-record-gcc-switches"

What did you do?

Run ssa on https://github.com/minio/minio. Reproducible by running govulncheck, which uses ssa:

govulncheck ./...

Also reproducible if govulncheck uses (the latest) v0.4.1-0.20221212161611-18f76ecd3f38 version of tools.

What did you expect to see?

No panic.

What did you see instead?

panic: in github.com/minio/minio/internal/config.Error: cannot convert *t0 (PT) to T

goroutine 16266 [running]:
golang.org/x/tools/go/ssa.emitConv(0xc06b569680, {0x9436a0, 0xc080fa2ea0}, {0x93fcb8?, 0xc052874180})
       [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/emit.go:295 +0xa2c
golang.org/x/tools/go/ssa.(*builder).stmt(0xc080f9acc0?, 0xc06b569680, {0x941208?, 0xc04c2a2fc0?})
        [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:2220 +0x1145
golang.org/x/tools/go/ssa.(*builder).stmtList(0x40d11d?, 0x849dc0?, {0xc03c94cac0?, 0x3, 0xc080fa41b0?})
        [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:946 +0x45
golang.org/x/tools/go/ssa.(*builder).stmt(0xc06b569680?, 0xc06b569680, {0x940c68?, 0xc04cb0cd80?})
        [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:2277 +0x859
golang.org/x/tools/go/ssa.(*builder).buildFunctionBody(0x656791?, 0xc06b569680)
       [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:2391 +0x437
golang.org/x/tools/go/ssa.(*builder).buildFunction(0x6567e0?, 0xc06b569680)
        [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:2326 +0x2e
golang.org/x/tools/go/ssa.(*builder).buildCreated(0xc076503e18)
        [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:2413 +0x25
golang.org/x/tools/go/ssa.(*Package).build(0xc06b508980)
        [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:2606 +0xc86
sync.(*Once).doSlow(0xc00260cfb8?, 0x608ede?)
        [redacted]/src/sync/once.go:74 +0xc2
sync.(*Once).Do(...)
        [redacted]/src/sync/once.go:65
golang.org/x/tools/go/ssa.(*Package).Build(...)
        [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:2477
golang.org/x/tools/go/ssa.(*Program).Build.func1(0x0?)
       [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:2462 +0x4c
created by golang.org/x/tools/go/ssa.(*Program).Build
        [redacted]/go/pkg/mod/golang.org/x/tools@v0.4.1-0.20221212161611-18f76ecd3f38/go/ssa/builder.go:2461 +0x19c

It looks like this is the function causing the panic. Perhaps a duplicate of #56849?

Thanks to @harshavardhana for reporting this.

cc @timothy-king

The text was updated successfully, but these errors were encountered:

timothy-king · 2022-12-13T17:28:48Z

Here is what seem to be the relevant bits:

type I interface { X | Y }

type X struct { v string }
type Y struct { X }

func Foo[T I, PT interface { *T }]() {
	_ = PT(new(T))
}

I don't think this seems to be about supporting arrays conversions or multiple distinct kinds of conversions. So I don't think this is a duplicate of #56849.

zpavlinovic · 2022-12-15T22:25:22Z

The issue could be in

func emitLoad(f *Function, addr Value) *UnOp {
	v := &UnOp{Op: token.MUL, X: addr}
	v.setType(deref(addr.Type()))
	f.emit(v)
	return v
}

Likely, deref is not picking the type under the pointer. addr.CoreType could be a solution here.

gopherbot · 2022-12-17T01:23:23Z

Change https://go.dev/cl/458235 mentions this issue: go/ssa: deref core type in emitLoad

gopherbot · 2022-12-17T01:42:16Z

Change https://go.dev/cl/458255 mentions this issue: all: update dependency to tools

Resolves some panics in ssa. Updates golang/go#57272 Change-Id: Icf2bb1d2e0c54f9cf8443e339dd0935019e887e6 Reviewed-on: https://go-review.googlesource.com/c/vuln/+/458255 Auto-Submit: Zvonimir Pavlinovic <zpavlinovic@google.com> Reviewed-by: Jonathan Amsterdam <jba@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> Run-TryBot: Zvonimir Pavlinovic <zpavlinovic@google.com>

gopherbot · 2023-03-20T09:17:38Z

Change https://go.dev/cl/477635 mentions this issue: go/ssa: deref core type in emitStore

Resolves some panics in ssa. Updates golang/go#57272 Change-Id: Icf2bb1d2e0c54f9cf8443e339dd0935019e887e6 Reviewed-on: https://go-review.googlesource.com/c/vuln/+/458255 Auto-Submit: Zvonimir Pavlinovic <zpavlinovic@google.com> Reviewed-by: Jonathan Amsterdam <jba@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> Run-TryBot: Zvonimir Pavlinovic <zpavlinovic@google.com>

gopherbot · 2023-05-04T16:23:08Z

Change https://go.dev/cl/492598 mentions this issue: go/ssa: use core type in address

The type of an address is now the element type of a type whose core type is a pointer type. Previously this was the element type of a type whose underlying type was a pointer type. emitStore now uses the core type as well. func f[M any, P *M](p P) { var m M *p = m } is emitted as: func f[M any, P *M](p P): 0: *p = *new(M):M return Related to golang/go#57272 Fixes golang/go#58633 Change-Id: I35d4345a9b3f69bcd28cf8342f7fec550329eba4 Reviewed-on: https://go-review.googlesource.com/c/tools/+/492598 TryBot-Result: Gopher Robot <gobot@golang.org> Run-TryBot: Tim King <taking@google.com> Reviewed-by: Alan Donovan <adonovan@google.com>

Resolves some panics in ssa. Updates golang/go#57272 Change-Id: Icf2bb1d2e0c54f9cf8443e339dd0935019e887e6 Reviewed-on: https://go-review.googlesource.com/c/vuln/+/458255 Auto-Submit: Zvonimir Pavlinovic <zpavlinovic@google.com> Reviewed-by: Jonathan Amsterdam <jba@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> Run-TryBot: Zvonimir Pavlinovic <zpavlinovic@google.com>

zpavlinovic added NeedsInvestigation Someone must examine and confirm this is a valid issue and not a duplicate of an existing one. Tools This label describes issues relating to any tools in the x/tools repository. labels Dec 13, 2022

zpavlinovic added this to the Unreleased milestone Dec 13, 2022

zpavlinovic self-assigned this Dec 15, 2022

zpavlinovic added the vulncheck or vulndb Issues for the x/vuln or x/vulndb repo label Dec 15, 2022

gopherbot closed this as completed in golang/tools@b4dfc36 Dec 17, 2022

zpavlinovic assigned timothy-king Dec 20, 2022

Antonboom mentioned this issue Mar 19, 2023

x/tools/go/ssa: ent.withHooks$1: cannot convert *t0 (M) to PM #58633

Closed

golang locked and limited conversation to collaborators May 3, 2024

gopherbot added the FrozenDueToAge label May 3, 2024

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

x/tools/go/ssa: emitConv panic on generics #57272

x/tools/go/ssa: emitConv panic on generics #57272

zpavlinovic commented Dec 13, 2022 •

edited

Loading

timothy-king commented Dec 13, 2022

zpavlinovic commented Dec 15, 2022

gopherbot commented Dec 17, 2022

gopherbot commented Dec 17, 2022

gopherbot commented Mar 20, 2023

gopherbot commented May 4, 2023

x/tools/go/ssa: emitConv panic on generics #57272

x/tools/go/ssa: emitConv panic on generics #57272

Comments

zpavlinovic commented Dec 13, 2022 • edited Loading

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

Does this issue reproduce with the latest release?

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

What did you do?

What did you expect to see?

What did you see instead?

timothy-king commented Dec 13, 2022

zpavlinovic commented Dec 15, 2022

gopherbot commented Dec 17, 2022

gopherbot commented Dec 17, 2022

gopherbot commented Mar 20, 2023

gopherbot commented May 4, 2023

zpavlinovic commented Dec 13, 2022 •

edited

Loading

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

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