cmd/compile: panic: First time we've seen filename (part II) #35652
Description
$ gotip version
go version devel +6ba0be1639 Sat Nov 16 20:31:45 2019 +0000 linux/amd64
The following code (minimized from a gosmith-generated program):
package p
func f() {
for true {
if true {
continue
}
}
}
crashes the tip compiler with this error:
$ gotip build crash.go
# command-line-arguments
panic: First time we've seen filename: "gofile..??"
goroutine 49 [running]:
cmd/internal/obj.(*Link).generateDebugLinesSymbol(0xc000378ea0, 0xc000553d00, 0xc000553f00)
/home/alberto/go/src/cmd/internal/obj/dwarf.go:43 +0x8e3
cmd/internal/obj.(*Link).populateDWARF(0xc000378ea0, 0xe40dc0, 0xc000166160, 0xc000553d00, 0x7fff3ca56300, 0x16)
/home/alberto/go/src/cmd/internal/obj/objfile.go:619 +0x31c
cmd/internal/obj.Flushplist(0xc000378ea0, 0xc00058bea8, 0xc000048250, 0x7fff3ca56300, 0x16)
/home/alberto/go/src/cmd/internal/obj/plist.go:112 +0x7d8
cmd/compile/internal/gc.(*Progs).Flush(0xc00058c1c0)
/home/alberto/go/src/cmd/compile/internal/gc/gsubr.go:94 +0xbc
cmd/compile/internal/gc.compileSSA(0xc000166160, 0x0)
/home/alberto/go/src/cmd/compile/internal/gc/pgen.go:323 +0x690
cmd/compile/internal/gc.compileFunctions.func2(0xc000554d20, 0xc0005560f0, 0x0)
/home/alberto/go/src/cmd/compile/internal/gc/pgen.go:363 +0x49
created by cmd/compile/internal/gc.compileFunctions
/home/alberto/go/src/cmd/compile/internal/gc/pgen.go:361 +0x128
It compiles fine on Go1.13.4.
This appears to be related to the compiler crash previously reported in #34520.