internal/syscall/windows: change WSAMsg.Name type
The problem was discovered while running
go test -a -short -gcflags=all=-d=checkptr -run=TestUDPConnSpecificMethods net
WSAMsg is type defined by Windows. And WSAMsg.Name could point to two
different structures for IPv4 and IPV6 sockets.
Currently WSAMsg.Name is declared as *syscall.RawSockaddrAny. But that
violates
(1) Conversion of a *T1 to Pointer to *T2.
rule of
https://golang.org/pkg/unsafe/#Pointer
When we convert *syscall.RawSockaddrInet4 into *syscall.RawSockaddrAny,
syscall.RawSockaddrInet4 and syscall.RawSockaddrAny do not share an
equivalent memory layout.
Same for *syscall.SockaddrInet6 into *syscall.RawSockaddrAny.
This CL changes WSAMsg.Name type to *syscall.Pointer. syscall.Pointer
length is 0, and that at least makes type checker happy.
After this change I was able to run
go test -a -short -gcflags=all=-d=checkptr std cmd
without type checker complaining.
Updates #34972
Change-Id: Ic5c2321c20abd805c687ee16ef6f643a2f8cd93f
Reviewed-on: https://go-review.googlesource.com/c/go/+/222457
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/src/internal/poll/fd_windows.go b/src/internal/poll/fd_windows.go
index 4b2623e..1a0bdb3 100644
--- a/src/internal/poll/fd_windows.go
+++ b/src/internal/poll/fd_windows.go
@@ -999,7 +999,7 @@
o := &fd.rop
o.InitMsg(p, oob)
o.rsa = new(syscall.RawSockaddrAny)
- o.msg.Name = o.rsa
+ o.msg.Name = (syscall.Pointer)(unsafe.Pointer(o.rsa))
o.msg.Namelen = int32(unsafe.Sizeof(*o.rsa))
n, err := execIO(o, func(o *operation) error {
return windows.WSARecvMsg(o.fd.Sysfd, &o.msg, &o.qty, &o.o, nil)
@@ -1030,7 +1030,7 @@
if err != nil {
return 0, 0, err
}
- o.msg.Name = (*syscall.RawSockaddrAny)(rsa)
+ o.msg.Name = (syscall.Pointer)(rsa)
o.msg.Namelen = len
}
n, err := execIO(o, func(o *operation) error {
diff --git a/src/internal/syscall/windows/syscall_windows.go b/src/internal/syscall/windows/syscall_windows.go
index dc64111..f299adc 100644
--- a/src/internal/syscall/windows/syscall_windows.go
+++ b/src/internal/syscall/windows/syscall_windows.go
@@ -176,7 +176,7 @@
}
type WSAMsg struct {
- Name *syscall.RawSockaddrAny
+ Name syscall.Pointer
Namelen int32
Buffers *syscall.WSABuf
BufferCount uint32
