Jenkins job build hangs, dead lock for pipline process. No other build can be build when it hangs.
see job console, It stays like this until you abort the job build.

below you can see that the same bat script calls hangs on a locked java.io.BufferedInputStream@a92403. 

This happens 7 out of 10 builds. It is really a pain in the ass.

job console:

[Workspace] $ cmd /c call C:\Users\KZ\AppData\Local\Temp\jenkins7011635632695808959.bat

c:\JenkinsJobs\test_054EB_build\Workspace>cd Product.054EB/Workdir/
— Building project in Release mode —

IAR Command Line Build Utility V6.4.4.0
Copyright 2002-2012 IAR Systems AB.

Deleting outputs for configuration Release
Updating build tree...

110 file(s) deleted.

ThreadDump:

cmd /c call C:\Users\KZ\AppData\Local\Temp\jenkins7011635632695808959.bat: stdout copier

"cmd /c call C:\Users\KZ\AppData\Local\Temp\jenkins7011635632695808959.bat: stdout copier" Id=40731 Group=main RUNNABLE (in native)

at java.io.FileInputStream.readBytes(Native Method)

at java.io.FileInputStream.read(Unknown Source)

at java.io.BufferedInputStream.read1(Unknown Source)

at java.io.BufferedInputStream.read(Unknown Source)

• locked java.io.BufferedInputStream@a92403

at java.io.FilterInputStream.read(Unknown Source)

at hudson.util.StreamCopyThread.run(StreamCopyThread.java:60)