cmd/compile: internal compiler error: bad live variable at entry (part 2) #29218
Description
$ gotip version
go version devel +9eb383e8f0 Thu Dec 13 17:10:32 2018 +0000 linux/amd64
The following program
package p
type T struct {
b bool
string
}
func f() {
var b bool
var t T
for {
switch &t.b {
case &b:
if b {
}
}
}
}
crashes the tip compiler with:
$ gotip build crash.go
# command-line-arguments
<autogenerated>:1: internal compiler error: bad live variable at entry of f: t (type T)
goroutine 34 [running]:
runtime/debug.Stack(0xf58560, 0xc00000e018, 0x0)
/home/alberto/go/src/runtime/debug/stack.go:24 +0x9d
cmd/compile/internal/gc.Fatalf(0xdd8845, 0x24, 0xc00052f850, 0x2, 0x2)
/home/alberto/go/src/cmd/compile/internal/gc/subr.go:190 +0x28b
cmd/compile/internal/gc.(*Liveness).epilogue(0xc0000c4640)
/home/alberto/go/src/cmd/compile/internal/gc/plive.go:1004 +0xc03
cmd/compile/internal/gc.liveness(0xc0004a80f0, 0xc0004ba6e0, 0xc0000c2d90, 0xdc4002, 0x8, 0xde8130)
/home/alberto/go/src/cmd/compile/internal/gc/plive.go:1399 +0xc4
cmd/compile/internal/gc.genssa(0xc0004ba6e0, 0xc0000c2d90)
/home/alberto/go/src/cmd/compile/internal/gc/ssa.go:5088 +0x92
cmd/compile/internal/gc.compileSSA(0xc0000bc420, 0x0)
/home/alberto/go/src/cmd/compile/internal/gc/pgen.go:290 +0x372
cmd/compile/internal/gc.compileFunctions.func2(0xc00049fc20, 0xc0004a0370, 0x0)
/home/alberto/go/src/cmd/compile/internal/gc/pgen.go:345 +0x49
created by cmd/compile/internal/gc.compileFunctions
/home/alberto/go/src/cmd/compile/internal/gc/pgen.go:343 +0x128
It compiles fine on go1.11.
The crash looks similar to the one in #28445, but the toolchain I'm fuzzing includes the fix for that one.