go/types, types2: crash in typesSummary (which assumes well-typedness)

[adonovan]

This program crashes the type checker:

package a

var x int

func f(...any)

var _ = f(0, x...)

both in the compiler:

~$ cd w/goroot/src

src$ git log -1 | grep commit
commit 5050e37dbf723e3689721519eddb704dfdd7148e
src$ cat  ../../xtools/a.go
package a

var x int

func f(...any)

var _ = f(0, x...)

src$ go tool compile   ../../xtools/a.go
<unknown line number>: internal compiler error: panic: interface conversion: syntax.Type is *types2.Basic, not *types2.Slice

goroutine 1 [running]:
runtime/debug.Stack()
	/Users/adonovan/w/goroot/src/runtime/debug/stack.go:26 +0x64
cmd/compile/internal/base.FatalfAt({0x341a8?, 0x140?}, {0x100c583d9, 0x9}, {0x140000341d8, 0x1, 0x1})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/base/print.go:230 +0x20c
cmd/compile/internal/base.Fatalf(...)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/base/print.go:195
cmd/compile/internal/gc.handlePanic()
	/Users/adonovan/w/goroot/src/cmd/compile/internal/gc/main.go:54 +0x8c
panic({0x100e48660?, 0x140003c67b0?})
	/Users/adonovan/w/goroot/src/runtime/panic.go:787 +0x124
cmd/compile/internal/types2.(*Checker).handleBailout(0x14000003880, 0x140000351f8)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/check.go:396 +0x98
panic({0x100e48660?, 0x140003c67b0?})
	/Users/adonovan/w/goroot/src/runtime/panic.go:787 +0x124
cmd/compile/internal/types2.(*Checker).typesSummary(0x14000003880, {0x1400001f480?, 0x2, 0x100c6ebb1?}, 0x1)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/assignments.go:320 +0x3ac
cmd/compile/internal/types2.(*Checker).arguments(0x14000003880, 0x14000138b60, 0x140003f8dc0, {0x0, 0x0, 0x0}, {0x0, 0x0, 0x0}, {0x14000030aa0, ...}, ...)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/call.go:533 +0x1294
cmd/compile/internal/types2.(*Checker).callExpr(0x14000003880, 0x140003f8e80, 0x14000138b60)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/call.go:296 +0x464
cmd/compile/internal/types2.(*Checker).exprInternal(0x14000003880, 0x0, 0x140003f8e80, {0x100edfdd8, 0x14000138b60}, {0x0?, 0x0?})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/expr.go:1104 +0x204
cmd/compile/internal/types2.(*Checker).rawExpr(0x14000003880, 0x0, 0x140003f8e80, {0x100edfdd8?, 0x14000138b60?}, {0x0?, 0x0?}, 0x0)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/expr.go:959 +0x128
cmd/compile/internal/types2.(*Checker).expr(0x14000003880, 0x0?, 0x140003f8e80, {0x100edfdd8?, 0x14000138b60?})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/expr.go:1275 +0x38
cmd/compile/internal/types2.(*Checker).varDecl(0x14000003880, 0x14000138f50, {0x14000062700, 0x1, 0x1}, {0x0, 0x0}, {0x100edfdd8, 0x14000138b60})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/decl.go:431 +0x13c
cmd/compile/internal/types2.(*Checker).objDecl(0x14000003880, {0x100ee45a0, 0x14000138f50}, 0x0)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/decl.go:186 +0x818
cmd/compile/internal/types2.(*Checker).packageObjects(...)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/resolver.go:695
cmd/compile/internal/types2.(*Checker).checkFiles(0x14000003880, {0x140000626d8?, 0x1014fe920?, 0x14000003880?})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/check.go:451 +0x694
cmd/compile/internal/types2.(*Checker).Files(0x100ec6fc0?, {0x140000626d8?, 0x0?, 0x0?})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/check.go:414 +0x80
cmd/compile/internal/types2.(*Config).Check(0x14000138bd0, {0x100c5d6d0?, 0x1400000e077?}, {0x140000626d8, 0x1, 0x1}, 0x140003fc5a0)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/types2/api.go:480 +0x134
cmd/compile/internal/noder.checkFiles({0x0, {0x0, 0x0}}, {0x140000626a8, 0x1, 0x14000035488?})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/noder/irgen.go:95 +0x4b4
cmd/compile/internal/noder.writePkgStub({0x0?, {0x0?, 0x0?}}, {0x140000626a8, 0x1, 0x1})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/noder/unified.go:319 +0x48
cmd/compile/internal/noder.unified({0x0?, {0x0?, 0x0?}}, {0x140000626a8?, 0x100e0acc0?, 0x0?})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/noder/unified.go:195 +0xb4
cmd/compile/internal/noder.LoadPackage({0x1400001e130, 0x1, 0x1})
	/Users/adonovan/w/goroot/src/cmd/compile/internal/noder/noder.go:77 +0x398
cmd/compile/internal/gc.Main(0x100ed4220)
	/Users/adonovan/w/goroot/src/cmd/compile/internal/gc/main.go:208 +0xc10
main.main()
	/Users/adonovan/w/goroot/src/cmd/compile/main.go:57 +0x110
src$ 

and go/types, here demonstrated via gopls:

xtools$ go version
go version devel go1.24-a86ea80197 Thu Nov 21 19:44:18 2024 +0000 darwin/arm64

xtools$ git log -1 | head -n 1
commit 1e0d4ee6a4771f70b0f2625329c97b4103b69d09

xtools$ cat a.go 
package a

var x int

func f(...any)

var _ = f(0, x...)

xtools$ go run ./gopls check a.go
panic: interface conversion: types.Type is *types.Basic, not *types.Slice [recovered]
	panic: interface conversion: types.Type is *types.Basic, not *types.Slice

goroutine 3271 gp=0x14000502540 m=8 mp=0x14000580008 [running]:
panic({0x1057938a0?, 0x1400ac92b70?})
	/Users/adonovan/w/goroot/src/runtime/panic.go:806 +0x154 fp=0x140081407d0 sp=0x14008140720 pc=0x104a82584
go/types.(*Checker).handleBailout(0x14000102e00, 0x140081417c8)
	/Users/adonovan/w/goroot/src/go/types/check.go:421 +0x98 fp=0x140081407f0 sp=0x140081407d0 pc=0x104de1918
go/types.(*Checker).Files.deferwrap1()
	/Users/adonovan/w/goroot/src/go/types/check.go:438 +0x2c fp=0x14008140810 sp=0x140081407f0 pc=0x104de1a3c
panic({0x1057938a0?, 0x1400ac92b70?})
	/Users/adonovan/w/goroot/src/runtime/panic.go:787 +0x124 fp=0x140081408c0 sp=0x14008140810 pc=0x104a82554
runtime.panicdottypeE(...)
	/Users/adonovan/w/goroot/src/runtime/iface.go:275
runtime.panicdottypeI(0x1058e7568?, 0x1057c5c20, 0x1057a6680)
	/Users/adonovan/w/goroot/src/runtime/iface.go:285 +0x70 fp=0x140081408f0 sp=0x140081408c0 pc=0x104a1ffa0
go/types.(*Checker).typesSummary(0x14000102e00, {0x1400a76cac0?, 0x2, 0x14008140d20?}, 0x1)
	/Users/adonovan/w/goroot/src/go/types/assignments.go:323 +0x3ac fp=0x140081409a0 sp=0x140081408f0 pc=0x104dd342c
go/types.(*Checker).arguments(0x14000102e00, 0x1400ac90780, 0x1400ac90940, {0x0, 0x0, 0x0}, {0x0, 0x0, 0x0}, {0x1400a76e760, ...}, ...)
	/Users/adonovan/w/goroot/src/go/types/call.go:533 +0x162c fp=0x14008140db0 sp=0x140081409a0 pc=0x104ddeefc
go/types.(*Checker).callExpr(0x14000102e00, 0x1400ac90a00, 0x1400ac90780)
	/Users/adonovan/w/goroot/src/go/types/call.go:298 +0x5bc fp=0x140081410a0 sp=0x14008140db0 pc=0x104ddc0ec
go/types.(*Checker).exprInternal(0x14000102e00, 0x104a2311c?, 0x1400ac90a00, {0x1058ebc60, 0x1400ac90780}, {0x0?, 0x0?})
	/Users/adonovan/w/goroot/src/go/types/expr.go:1088 +0x19c fp=0x140081411d0 sp=0x140081410a0 pc=0x104df24dc
go/types.(*Checker).rawExpr(0x14000102e00, 0x0, 0x1400ac90a00, {0x1058ebc60?, 0x1400ac90780?}, {0x0?, 0x0?}, 0x0)
	/Users/adonovan/w/goroot/src/go/types/expr.go:952 +0x120 fp=0x14008141270 sp=0x140081411d0 pc=0x104df1f10
go/types.(*Checker).expr(0x14000102e00, 0x0?, 0x1400ac90a00, {0x1058ebc60?, 0x1400ac90780?})
	/Users/adonovan/w/goroot/src/go/types/expr.go:1227 +0x38 fp=0x140081412c0 sp=0x14008141270 pc=0x104df3768
go/types.(*Checker).varDecl(0x14000102e00, 0x1400ac8e660, {0x1400011d828, 0x1, 0x1}, {0x0, 0x0}, {0x1058ebc60, 0x1400ac90780})
	/Users/adonovan/w/goroot/src/go/types/decl.go:506 +0x13c fp=0x14008141330 sp=0x140081412c0 pc=0x104de925c
go/types.(*Checker).objDecl(0x14000102e00, {0x1058fac38, 0x1400ac8e660}, 0x0)
	/Users/adonovan/w/goroot/src/go/types/decl.go:187 +0x7dc fp=0x14008141560 sp=0x14008141330 pc=0x104de6a6c
go/types.(*Checker).packageObjects(0x14000102e00)
	/Users/adonovan/w/goroot/src/go/types/resolver.go:690 +0x404 fp=0x140081416a0 sp=0x14008141560 pc=0x104e15374
go/types.(*Checker).checkFiles(0x14000102e00, {0x1400011d800?, 0x8?, 0x105798d20?})
	/Users/adonovan/w/goroot/src/go/types/check.go:476 +0x2b0 fp=0x14008141790 sp=0x140081416a0 pc=0x104de1d20
go/types.(*Checker).Files(0x0?, {0x1400011d800?, 0x1400ac8e2a0?, 0x1400ac96000?})
	/Users/adonovan/w/goroot/src/go/types/check.go:439 +0x80 fp=0x14008141800 sp=0x14008141790 pc=0x104de19b0
golang.org/x/tools/gopls/internal/cache.(*typeCheckBatch).checkPackage(0x1400ac90380, {0x1058ed058, 0x1400a771f20}, 0x1400ac90340, 0x1400ac94000, 0x1400ac923f0)
	/Users/adonovan/w/xtools/gopls/internal/cache/check.go:1543 +0x730 fp=0x14008141b90 sp=0x14008141800 pc=0x1051a3ed0
golang.org/x/tools/gopls/internal/cache.(*typeCheckBatch).getPackage.func1({0x1058ed058, 0x1400a771f20})
	/Users/adonovan/w/xtools/gopls/internal/cache/check.go:420 +0x2c0 fp=0x14008141d10 sp=0x14008141b90 pc=0x10519d460
golang.org/x/tools/gopls/internal/cache.(*futureCache[...]).get(0x1058eb260, {0x1058ed058, 0x1400a771f20}, {0x14000037a70, 0x12}, 0x140000b1e70)
	/Users/adonovan/w/xtools/gopls/internal/cache/future.go:126 +0x360 fp=0x14008141e30 sp=0x14008141d10 pc=0x1051de400
golang.org/x/tools/gopls/internal/cache.(*typeCheckBatch).getPackage(0x1058ed001?, {0x1058ed058?, 0x1400a771f20?}, 0x10519cce4?)
	/Users/adonovan/w/xtools/gopls/internal/cache/check.go:371 +0x5c fp=0x14008141e90 sp=0x14008141e30 pc=0x10519d16c
golang.org/x/tools/gopls/internal/cache.(*typeCheckBatch).handleSyntaxPackage(0x1400ac90380, {0x1058ed058, 0x1400a771f20}, 0x0, {0x14000037a70?, 0x0?}, 0x1400ac92360, 0x1400ac90540)
	/Users/adonovan/w/xtools/gopls/internal/cache/check.go:360 +0x88 fp=0x14008141ed0 sp=0x14008141e90 pc=0x10519d058
golang.org/x/tools/gopls/internal/cache.(*typeCheckBatch).query.func1()
	/Users/adonovan/w/xtools/gopls/internal/cache/check.go:298 +0xa8 fp=0x14008141f60 sp=0x14008141ed0 pc=0x10519cd28
golang.org/x/sync/errgroup.(*Group).Go.func1()
	/Users/adonovan/go/pkg/mod/golang.org/x/sync@v0.9.0/errgroup/errgroup.go:78 +0x54 fp=0x14008141fd0 sp=0x14008141f60 pc=0x104b44554
runtime.goexit({})
	/Users/adonovan/w/goroot/src/runtime/asm_arm64.s:1260 +0x4 fp=0x14008141fd0 sp=0x14008141fd0 pc=0x104a8ab94
created by golang.org/x/sync/errgroup.(*Group).Go in goroutine 3269
	/Users/adonovan/go/pkg/mod/golang.org/x/sync@v0.9.0/errgroup/errgroup.go:75 +0x94

etc

[gabyhelp]

Related Issues

• x/tools/gopls: panic in analyzer due to type checker errors #32413 (closed)
• x/tools/gopls: types.Func.typ=nil panic in missingMethod with gopls@master built with go@master #59848 (closed)
• x/tools/go/types: panics on invalid constant #11325 (closed)
• go/types: assertion failed #11347 (closed)
• x/tools/gopls: automated issue report (crash): file not found for pos = 1 (-) #66790
• go/types, types2: gopls crash on method with type parameters #50427 (closed)
• go.tools/go.types: goto _ crashes type checker #7537 (closed)
• x/tools/gopls: automated issue report (crash) #45183 (closed)
• x/tools/gopls: unrecovered panic when type checking #52210 (closed)
• x/tools/gopls: panic in go/types #45434 (closed)

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[findleyr]

CC @griesemer

Tentatively putting this in the 1.24 milestone, as it is a crash that is affecting users.

[griesemer]

I'll fix this, seems pretty straight-forward and safe to do.

[gopherbot]

Change https://go.dev/cl/632275 mentions this issue: go/types, types2: fix printing of error message with variadic calls