cmd/compile: stack overflow with a recursive type #22904
Description
What version of Go are you using (go version)?
go version go1.9 linux/amd64
Does this issue reproduce with the latest release?
Yes
What operating system and processor architecture are you using (go env)?
GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/yann/go"
GORACE=""
GOROOT="/usr/local/go"
GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build782515074=/tmp/go-build -gno-record-gcc-switches"
CXX="g++"
CGO_ENABLED="1"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
What did you do?
go build this program
package main
import "fmt"
type a struct {
b
}
type b struct {
a
}
func main() {
fmt.Println(a{})
}What did you expect to see?
Probably the invalid recursive type error message
What did you see instead?
cmd/compile crashes with the following stack overflow.
runtime: goroutine stack exceeds 1000000000-byte limit
fatal error: stack overflow
runtime stack:
runtime.throw(0xb5d565, 0xe)
/usr/local/go/src/runtime/panic.go:605 +0x95
runtime.newstack(0x0)
/usr/local/go/src/runtime/stack.go:1050 +0x6e1
runtime.morestack()
/usr/local/go/src/runtime/asm_amd64.s:415 +0x86
goroutine 1 [running]:
cmd/compile/internal/types.(*Type).Fields(0xc42038ed80, 0x0)
/usr/local/go/src/cmd/compile/internal/types/type.go:813 +0x177 fp=0xc440382360 sp=0xc440382358 pc=0x4d7907
cmd/compile/internal/types.(*Fields).Len(...)
/usr/local/go/src/cmd/compile/internal/types/type.go:1277
cmd/compile/internal/types.(*Type).NumFields(0xc42038ed80, 0xc42038ee40)
/usr/local/go/src/cmd/compile/internal/types/type.go:1277 +0x2b fp=0xc440382380 sp=0xc440382360 pc=0x4d937b
cmd/compile/internal/gc.isdirectiface(0xc42038ed80, 0x0)
/usr/local/go/src/cmd/compile/internal/gc/subr.go:2045 +0xbd fp=0xc4403823a8 sp=0xc440382380 pc=0xa3157d
cmd/compile/internal/gc.isdirectiface(0xc42038ee40, 0x0)
/usr/local/go/src/cmd/compile/internal/gc/subr.go:2045 +0x101 fp=0xc4403823d0 sp=0xc4403823a8 pc=0xa315c1