cmd/link: missing arg stack map for functions defined in different package #24419
Description
What version of Go are you using (go version)?
tip (86a3389)
Does this issue reproduce with the latest release?
yes
What did you do?
https://play.golang.org/p/4-OeiC68PO4
package main
import "bytes"
func growstack(n int) {
if n > 0 {
growstack(n - 1)
}
}
func main() {
var x, y []byte
defer bytes.Compare(x, y) // on AMD64 bytes.Compare is implemented in internal/bytealg
growstack(10000) // trigger a stack grow
}
$ go run b.go
runtime: frame bytes.Compare untyped args 824634277936+56
fatal error: missing stackmap
runtime stack:
runtime.throw(0x1073aff, 0x10)
/Users/cherryyz/src/go-tip/src/runtime/panic.go:598 +0x72
runtime.adjustframe(0x7ffeefbff518, 0x7ffeefbff630, 0x10b3be0)
/Users/cherryyz/src/go-tip/src/runtime/stack.go:698 +0x578
runtime.tracebackdefers(0xc000000180, 0x1077300, 0x7ffeefbff630)
/Users/cherryyz/src/go-tip/src/runtime/traceback.go:73 +0xda
runtime.adjustdefers(0xc000000180, 0x7ffeefbff630)
/Users/cherryyz/src/go-tip/src/runtime/stack.go:733 +0x45
runtime.copystack(0xc000000180, 0x4000, 0x10c5f01)
/Users/cherryyz/src/go-tip/src/runtime/stack.go:878 +0x17e
runtime.newstack()
/Users/cherryyz/src/go-tip/src/runtime/stack.go:1063 +0x30e
runtime.morestack()
/Users/cherryyz/src/go-tip/src/runtime/asm_amd64.s:481 +0x8f
The stack map of bytes.Compare is missing.
The compiler does generate the stack map
$ go build -gcflags -S bytes
...
"".Compare.args_stackmap SRODATA size=12
0x0000 02 00 00 00 0e 00 00 00 09 00 09 00 ............
...
But it doesn't make into the binary. Apparently the linker dropped it on the floor?
This doesn't seem to be the case for assembly function defined in the same package.