Hello!
https://golang.org/src/runtime/symtab.go?s=7594:7745#L244
type Func struct {
opaque struct{} // unexported field to disallow conversions
}
func (f *Func) raw() *_func {
return (*_func)(unsafe.Pointer(f))
}
An empty struct Func (T1) is converted to a non-zero struct _func (T2).
>From the unsafe.Pointer documentation
(https://golang.org/pkg/unsafe/#Pointer):
> T1->T2 conversion is safe if T2 is no larger than T1 ... (shortened for
clarity)
I'm guessing that documentation probably meant "allocation size", not the
"static type size"?
T1 pointer can be obtained from the T2 allocation, so it's allocation size
can be different from the unsafe.Sizeof(T1{}).
Or it could be that runtime can violate that particular rule.
*My question*: is it same to convert T1<->T2 even if sizeof(T1)<sizeof(T2),
but the memory was allocated for the bigger object?
Thank you in advance.
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