misc/cgo/testcshared: skip TestGo2C2Go on Windows

For #27019
Fixes #49457

Change-Id: I398abb7b555196ced34a6dd04b68195bf8bbdd38
Reviewed-on: https://go-review.googlesource.com/c/go/+/365994
Trust: Ian Lance Taylor <[email protected]>
Run-TryBot: Ian Lance Taylor <[email protected]>
TryBot-Result: Go Bot <[email protected]>
Reviewed-by: Emmanuel Odeke <[email protected]>
Reviewed-by: Cherry Mui <[email protected]>
Reviewed-by: Patrik Nyblom <[email protected]>

Author: ianlancetaylor

misc/cgo/testcshared/cshared_test.go

@@ -781,10 +781,10 @@ func copyFile(t *testing.T, dst, src string) {
 
 func TestGo2C2Go(t *testing.T) {
 	switch GOOS {
-	case "darwin", "ios":
-		// Darwin shared libraries don't support the multiple
+	case "darwin", "ios", "windows":
+		// Non-ELF shared libraries don't support the multiple
 		// copies of the runtime package implied by this test.
-		t.Skip("linking c-shared into Go programs not supported on Darwin; issue 29061")
+		t.Skipf("linking c-shared into Go programs not supported on %s; issue 29061, 49457", GOOS)
 	case "android":
 		t.Skip("test fails on android; issue 29087")
 	}