address of the struct and add the size of the struct.

Cgo translates C types into equivalent unexported Go types.
Because the translations are unexported, a Go package should not
expose C types in its exported API: a C type used in one Go package
is different from the same C type used in another.

Any C function (even void functions) may be called in a multiple

			// walking the tree and copying it piecewise. If the directory tree
			// contains nested modules this could push a lot of unnecessary contents,
			// but for the golang.org/x repos it seems to be significantly (~2x)
			// faster than copying one file at a time (via filepath.WalkDir),
			// apparently due to high latency in 'adb' commands.
			if err := adb("push", modDir, deviceModDir); err != nil {