go/internal/gcimporter: index out of range panic importing runtime

[josharian]

Using commit e71e1fe:

$ ./make.bash
$ GOOS=linux GOARCH=arm go tool vet -asmdecl ./runtime

Result (after a bunch of vet complaints):

panic: runtime error: index out of range [recovered]
    panic: runtime error: index out of range

goroutine 1 [running]:
panic(0x282500, 0xc42000e160)
    /Users/josh/go/tip/src/runtime/panic.go:500 +0x1a0
go/types.(*Checker).handleBailout(0xc4200da2a0, 0xc42231b578)
    /Users/josh/go/tip/src/go/types/check.go:213 +0xae
panic(0x282500, 0xc42000e160)
    /Users/josh/go/tip/src/runtime/panic.go:458 +0x241
go/internal/gcimporter.(*importer).pkg(0xc42199c480, 0x1)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:134 +0x83
go/internal/gcimporter.(*importer).fieldName(0xc42199c480, 0xc422a89d10, 0x3e59c0, 0x3f88e0, 0xc422318590)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:505 +0xc4
go/internal/gcimporter.(*importer).field(0xc42199c480, 0xc422a89d10, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:454 +0x5e
go/internal/gcimporter.(*importer).fieldList(0xc42199c480, 0xc422a89d10, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:445 +0xed
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0xc422a89d10, 0xc422e92e10, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:358 +0xf83
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0x0, 0xc422318c10, 0x2019db)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:297 +0x24e
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0x0, 0xc42199c480, 0x46f000)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:367 +0x1e91
go/internal/gcimporter.(*importer).param(0xc42199c480, 0x0, 0x1, 0xc420d820d0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:531 +0x49
go/internal/gcimporter.(*importer).paramList(0xc42199c480, 0x0, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:525 +0xb2
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0xc422a89d10, 0x480, 0xc4223192f0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:315 +0x36b
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0xc422a89d10, 0xc422a89d10, 0xc422a86a60)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:367 +0x1e91
go/internal/gcimporter.(*importer).field(0xc42199c480, 0xc422a89d10, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:455 +0x9a
go/internal/gcimporter.(*importer).fieldList(0xc42199c480, 0xc422a89d10, 0x201900, 0x0, 0x0, 0x0, 0x0, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:445 +0xed
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0xc422a89d10, 0xc422e92bd0, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:358 +0xf83
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0xc422a89d10, 0x3, 0xc422e92930)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:297 +0x24e
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0xc422a89d10, 0x0, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:340 +0xd73
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0xc422a89d10, 0xc422a89d10, 0xc422a86a30)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:367 +0x1e91
go/internal/gcimporter.(*importer).field(0xc42199c480, 0xc422a89d10, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:455 +0x9a
go/internal/gcimporter.(*importer).fieldList(0xc42199c480, 0xc422a89d10, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:445 +0xed
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0xc422a89d10, 0xc422e92b40, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:358 +0xf83
go/internal/gcimporter.(*importer).typ(0xc42199c480, 0x0, 0x20d4aa, 0xc42199c480)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:297 +0x24e
go/internal/gcimporter.(*importer).obj(0xc42199c480, 0xfffffffffffffffd)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:197 +0x753
go/internal/gcimporter.BImportData(0xc420086d20, 0xc422c90000, 0x180f20, 0x1ffe00, 0xc420f5e411, 0x7, 0x0, 0x7, 0x8, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/bimport.go:96 +0x359
go/internal/gcimporter.Import(0xc420086d20, 0xc420f5e411, 0x7, 0xc4213050a0, 0x7, 0x0, 0x0, 0x0)
    /Users/josh/go/tip/src/go/internal/gcimporter/gcimporter.go:126 +0x559
go/importer.gcimports.ImportFrom(0xc420086d20, 0xc420f5e411, 0x7, 0xc4213050a0, 0x7, 0x0, 0x1, 0x2, 0x0)
    /Users/josh/go/tip/src/go/importer/importer.go:70 +0x67
go/types.(*Checker).collectObjects(0xc4200da2a0)
    /Users/josh/go/tip/src/go/types/resolver.go:196 +0x825
go/types.(*Checker).checkFiles(0xc4200da2a0, 0xc4229a0400, 0x24, 0x40, 0x0, 0x0)
    /Users/josh/go/tip/src/go/types/check.go:225 +0xaa
go/types.(*Checker).Files(0xc4200da2a0, 0xc4229a0400, 0x24, 0x40, 0xc4229e23f0, 0xc42231b5f0)
    /Users/josh/go/tip/src/go/types/check.go:218 +0x49
go/types.(*Config).Check(0xc420f7c7c0, 0xc4212a45d0, 0xc, 0xc421037bc0, 0xc4229a0400, 0x24, 0x40, 0xc4229e60a0, 0x401, 0xc4200001a0, ...)
    /Users/josh/go/tip/src/go/types/api.go:344 +0x1a3
main.(*Package).check(0xc4227d9f80, 0xc421037bc0, 0xc4229a0400, 0x24, 0x40, 0x0, 0xc422997500)
    /Users/josh/go/tip/src/cmd/vet/types.go:76 +0x36e
main.doPackage(0x7fff5fbff9c6, 0x9, 0xc42031cc00, 0x24, 0x40, 0xc42042d0e0, 0xc42042d0e0)
    /Users/josh/go/tip/src/cmd/vet/main.go:336 +0x996
main.doPackageDir(0x7fff5fbff9c6, 0x9)
    /Users/josh/go/tip/src/cmd/vet/main.go:289 +0x6cd
main.visit(0x7fff5fbff9c6, 0x9, 0x3e8440, 0xc4200896c0, 0x0, 0x0, 0x0, 0x0)
    /Users/josh/go/tip/src/cmd/vet/main.go:371 +0xf3
path/filepath.walk(0x7fff5fbff9c6, 0x9, 0x3e8440, 0xc4200896c0, 0x2eec68, 0x0, 0xc4200895f0)
    /Users/josh/go/tip/src/path/filepath/path.go:351 +0x81
path/filepath.Walk(0x7fff5fbff9c6, 0x9, 0x2eec68, 0xc, 0xc4200895f0)
    /Users/josh/go/tip/src/path/filepath/path.go:398 +0xd5
main.walkDir(0x7fff5fbff9c6, 0x9)
    /Users/josh/go/tip/src/cmd/vet/main.go:386 +0x41
main.main()
    /Users/josh/go/tip/src/cmd/vet/main.go:240 +0x2cb

@griesemer @mdempsky

[griesemer]

@josharian You probably have package files that were built with a prior version of the compiler.

That said, I think I need to be more cautious with internal format changes even during development. I will refine the internal version numbering so I can evolve the format w/o constantly breaking importers.

I think if you rebuild everything, the issue should go away. If it doesn't please update this issue. Thanks.

[josharian]

I ran make.bash; that should rebuild everything, no? If not, what should I run?

[josharian]

Oh never mind. I ran make.bash, but I needed to also run GOOS=linux GOARCH=arm go install std.

Can we make gcimporter detect old versions, request a re-install, and then bail? This problem comes up over and over again on the issue tracker, and even trips up old hands like me. :) I'll file a separate issue for that. Closing this one as user error.

[griesemer]

Yes, I added version handling in the export data just recently, but I didn't bump the number because I assumed that people working off tip rebuild everything when they update. It's also a bit more complicated than just bumping the number because we have x/tools/gcimporter15 which is used to handle legacy installed packages but must also handle newer ones. Looking into it.