Mustang b51+, Windows XP Prof
Open Font2DTest, click on any letter to zoom it, click on the Close button in the frame - see assertion:
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AWT Assertion Failure
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::GetObjectType(tmpDCList->hDC) == OBJ_DC
File '../../../src/windows/native/sun/windows/awt_Component.cpp', at line 7118
GetLastError() is 6 : The handle is invalid.
Do you want to break into the debugger?
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Possibly a regression from 6219278
Another way to see the problem is to run an application that creates a huge amount of threads and renders once in each thread; this will cause an HDC to be allocated for each thread and never released (the HDC objects should be released upon thread exit).