Major All of a sudden, some builds start failing. Closer inspection showed, that the perforce plugin stopped providing the "-P" option to p4.exe. I can't explain why. Going back to 1.3.24 didn't help (but i'm unsure if the roll-back performed correctly). Updating Jenkins to 1.546 didn't help either.
The log of a successful (old) build shows:
[EnvInject] - Loading node environment variables. Building on Slave WIN7 in workspace c:\jenkins\workspace\DEMO Deleting project workspace... done Using remote perforce client: Jenkins_DEMO--216826706 [DEMO] $ "c:\program files\perforce\p4" -P XXXXXXXXXXXXXXXXXXXX workspace -o Jenkins_DEMO--216826706 Note: .repository directory in workspace (if exists) is skipped during clean. Wiping workspace... Wiped workspace. Clean complete, took 5 ms [...]
A failed (new) build shows:
[EnvInject] - Loading node environment variables. Building on Slave WIN7 in workspace c:\jenkins\workspace\DEMO Deleting project workspace... done Using remote perforce client: Jenkins_DEMO--216826706 [DEMO] $ "c:\program files\perforce\p4.exe" workspace -o Jenkins_DEMO--216826706 Caught exception communicating with perforce. No output for: c:\program files\perforce\p4.exe workspace -o Jenkins_DEMO--216826706 com.tek42.perforce.PerforceException: No output for: c:\program files\perforce\p4.exe workspace -o Jenkins_DEMO--216826706 at com.tek42.perforce.parse.AbstractPerforceTemplate.getPerforceResponse(AbstractPerforceTemplate.java:408) at com.tek42.perforce.parse.AbstractPerforceTemplate.getPerforceResponse(AbstractPerforceTemplate.java:301) at com.tek42.perforce.parse.Workspaces.getWorkspace(Workspaces.java:61) at hudson.plugins.perforce.PerforceSCM.getPerforceWorkspace(PerforceSCM.java:1545) at hudson.plugins.perforce.PerforceSCM.getPerforceWorkspace(PerforceSCM.java:1506) at hudson.plugins.perforce.PerforceSCM.checkout(PerforceSCM.java:843) at hudson.model.AbstractProject.checkout(AbstractProject.java:1415) at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(AbstractBuild.java:652) at jenkins.scm.SCMCheckoutStrategy.checkout(SCMCheckoutStrategy.java:88) at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:561) at hudson.model.Run.execute(Run.java:1678) at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46) at hudson.model.ResourceController.execute(ResourceController.java:88) at hudson.model.Executor.run(Executor.java:231) ERROR: Unable to communicate with perforce. No output for: c:\program files\perforce\p4.exe workspace -o Jenkins_DEMO--216826706 [...]
[JENKINS-21271] Perforce plugin does not provide -P option anymore
Peter Schaefer-Hutter
added a comment - Traced down the issue to the EnvInject plugin which seems to clobber the environment entries set by the perforce plugin.
Peter Schaefer-Hutter
added a comment - Traced down the issue to the EnvInject plugin which seems to clobber the environment entries set by the perforce plugin. 
Update: I was able to trace-down the issue to the EnvInject Plugin. Disabling this plugin brings back the "-P" options. Obviously, the EnvInject Plugin clears the environment, so that the line "getEnv().getPassword()" in the perforce plugin source code returns an empty string.