RFR: 8185862: AWT Assertion Failure in ::GetDIBits(hBMDC, hBM, 0, 1, 0, gpBitmapInfo, 0) 'awt_Win32GraphicsDevice.cpp', at line 185 [v11]

[Phil Race]

On Thu, 7 Mar 2024 16:55:12 GMT, Christoph Langer <clanger at openjdk.org> wrote:

>> The assertions reported in the bug were observed spuriously and here and there broke tests in some Windows configurations.
>> For instance [JDK-8266129](https://bugs.openjdk.org/browse/JDK-8266129), [JDK-8269529](https://bugs.openjdk.org/browse/JDK-8269529) or [JDK-8323664](https://bugs.openjdk.org/browse/JDK-8323664) came up due to this.
>> 
>> The problem is that in Windows environments without a valid display, e.g. started by system services or via PowerShell Remoting, one sees a Monitor with name 'Windisc' in `EnumDisplayMonitors`.
>> However, it seems to be some kind of a pseudo device where you can not get a DC via `CreateDC`. This behavior/monitor type doesn't seem to be well documented, though.
>> 
>> I hereby modify the device initialization code to only count/detect monitors where CreateDC returns non-NULL in Devices.cpp. I also add some more checking/error handling to AwtWin32GraphicsDevice::Initialize() for correctness.
>> 
>> Furthermore, I re-enable the test `javax/swing/reliability/HangDuringStaticInitialization.java` for Windows Debug VMs, which reverts the fix from JDK-8269529 that should not be necessary any more.
>
> Christoph Langer has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Bring back verification of hBMDC and hBM

I think we are done with this.

If a DEBUG build is used for HEADFUL then the new VERIFY calls *might* cause a different failure mode, but that's the only risk I see, and it seems a very, very small one.

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Marked as reviewed by prr (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/17614#pullrequestreview-1923370884