[OpenJDK 2D-Dev] ] [9] Review Request: 8156723: JVM crash at sun.java2d.windows.GDIBlitLoops.nativeBlit

[Mikhail Cherkasov]

Hi all,

Please review the fix:
http://cr.openjdk.java.net/~mcherkas/8156723/webrev/
for https://bugs.openjdk.java.net/browse/JDK-8156723 .
To reproduce the issue there relatively complicate steps:
1. connect external monitor to laptop, set laptop screen as the main screen
2. open SwingSet2
3. set second screen as main screen
4. move SwingSet2 to second screen and maximize it
5. disconnect external monitor from the laptop
6. jvm is crashed

after this steps wsdo->device becomes null there:
http://hg.openjdk.java.net/jdk9/jdk9/jdk/file/0086eb10182b/src/java.desktop/windows/native/libawt/java2d/windows/GDIWindowSurfaceData.cpp#l131 
and JVM crashes.
I'm not sure about root causes of this issue, but simple null-check 
fixes the issue.

Thanks,
Mikhail.