x/tools/gopls: Hover: nil deref in golang.StdSymbolOf

[adonovan]

#!stacks
"runtime.sigpanic" && "hover:+472"

Issue created by stacks.

	// Handle Method.
	if fn, _ := obj.(*types.Func); fn != nil {
		isPtr, named := typesinternal.ReceiverNamed(fn.Signature().Recv())         //   --panic--
		if isPackageLevel(named.Obj()) {
			for _, s := range symbols {

This stack J7Opuw was reported by telemetry:

• crash/crash
• runtime.gopanic:+69
• runtime.panicmem:=262
• runtime.sigpanic:+19
• golang.org/x/tools/gopls/internal/golang.StdSymbolOf:+27
• golang.org/x/tools/gopls/internal/golang.hover:+472
• golang.org/x/tools/gopls/internal/golang.Hover:+4
• golang.org/x/tools/gopls/internal/server.(*server).Hover:+30
• golang.org/x/tools/gopls/internal/protocol.serverDispatch:+335
• golang.org/x/tools/gopls/internal/lsprpc.(*streamServer).ServeStream.ServerHandler.func3:+5
• golang.org/x/tools/gopls/internal/lsprpc.(*streamServer).ServeStream.handshaker.func4:+52
• golang.org/x/tools/gopls/internal/protocol.Handlers.MustReplyHandler.func1:+2
• golang.org/x/tools/gopls/internal/protocol.Handlers.AsyncHandler.func2.2:+3
• runtime.goexit:+0

golang.org/x/tools/gopls@v0.17.1 go1.23.4 darwin/arm64 vscode (1)
golang.org/x/tools/gopls@v0.17.0 go1.23.4 linux/amd64 vscode (1)

Dups: 9xr_OA

[gabyhelp]

Related Issues

• x/tools/gopls: Hover: nil deref in parseDocLink #70635 (closed)
• x/tools/gopls: crash in Hover (telemetry) #69362
• x/tools/gopls: Hover: panic in lookup{ObjectByName,DocLinkSymbol} #69616
• x/tools/gopls: panic in hover #52211 (closed)
• x/tools/gopls: nil Signature (?) deref in Completion #70634 (closed)
• x/tools/gopls: Hover bug reported by telemetry [PE4R3g] #64244 (closed)
• x/tools/gopls: automated issue report (crash) #44300 (closed)
• x/tools/gopls: bug report in GetIfaceStubInfo #70666
• gopls: automated issue report (crash) #40464 (closed)
• x/tools/gopls: Hover bug reported by telemetry #66857 (closed)

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[adonovan]

I assume there's the usual off-by-one in the line numbering and that the actual panic is the named.Obj dereference.

[gopherbot]

Change https://go.dev/cl/638597 mentions this issue: gopls/internal/golang: check for nil ReceiverNamed

[adonovan]

Fixed by https://go.dev/cl/638597.