package main

import (
    "reflect"
)

func main() {
    fv := reflect.ValueOf(func([256]*byte){})
    fv.Call([]reflect.Value{reflect.ValueOf([256]*byte{})})
}


go run foo.go

panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xb code=0x1 addr=0x0 pc=0x4398f0]

goroutine 1 [running]:
reflect.(*gcProg).appendProg(0xc20801e040, 0x459ce0)
    /home/iant/go/src/reflect/type.go:1524 +0x190
reflect.funcLayout(0x45d680, 0x0, 0x459ce0, 0x459c01, 0x7f02c6b6d4e8, 0xc20801e020)
    /home/iant/go/src/reflect/type.go:1805 +0x606
reflect.Value.call(0x45d680, 0x4975f0, 0x0, 0x130, 0x47f1a0, 0x4, 0xc20802b750, 0x1,
0x1, 0x0, ...)
    /home/iant/go/src/reflect/value.go:485 +0xeed
reflect.Value.Call(0x45d680, 0x4975f0, 0x0, 0x130, 0xc20802b750, 0x1, 0x1, 0x0, 0x0, 0x0)
    /home/iant/go/src/reflect/value.go:388 +0xd2
main.main()
    /home/iant/foo.go:9 +0x1b7

goroutine 2 [runnable]:
runtime.forcegchelper()
    /home/iant/go/src/runtime/proc.go:90
runtime.goexit()
    /home/iant/go/src/runtime/proc.c:1651

goroutine 3 [runnable]:
runtime.bgsweep()
    /home/iant/go/src/runtime/mgc0.go:66
runtime.goexit()
    /home/iant/go/src/runtime/proc.c:1651


The problem is that the code in reflect/type.go gcProg.appendProg does not consider the
case in which the first word in t.gc is nil.  This case arises for large objects: ones
with more than 128 pointers.