I think the latest jtreg found this problem with the testcase leaving a file open. Since it was the last test, probably was missed before.

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warning: failed to delete C:\temp\jprt\T1\T\181227.ohair\source\build\windows-i586\testoutput\jdk_nio2\JTwork\java\nio\MappedByteBuffer\Force\Blah
TEST: java/nio/MappedByteBuffer/Force.java
JDK under test: (C:\temp\jprt\T1\T\181227~1.OHA\TESTPR~1\WINDOW~1.0-P)
openjdk version "1.7.0-201005281812.ohair.jdk"
OpenJDK Runtime Environment (build 1.7.0-201005281812.ohair.jdk-jprtadm_2010_05_28_16_28-b00)
Java HotSpot(TM) Client VM (build 19.0-b01, mixed mode, sharing)
Test result (overridden): Passed. Execution successful


ACTION: build -- Passed. Build successful
REASON: Named class compiled on demand
TIME: 0.547 seconds
messages:
command: build Force
reason: Named class compiled on demand
elapsed time (seconds): 0.547

ACTION: compile -- Passed. Compilation successful
REASON: .class file out of date or does not exist
TIME: 0.547 seconds
messages:
command: compile C:\temp\jprt\T1\T\181227.ohair\source\test\java\nio\MappedByteBuffer\Force.java
reason: .class file out of date or does not exist
elapsed time (seconds): 0.547
STDOUT:
STDERR:

ACTION: main -- Passed. Execution successful
REASON: Assumed action based on file name: run main Force
TIME: 0.109 seconds
messages:
command: main Force
reason: Assumed action based on file name: run main Force
elapsed time (seconds): 0.109
STDOUT:
STDERR:
STATUS:Passed.

TEST RESULT: Error. failed to clean up files after test
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