I have a Freestyle project job which has been working for over 40 runs but now gets the error below at the end of each build.  I have created another job copying the configuration of this one and it runs without getting the error.  This error stops the trigger of downstream jobs but doesn't appear to hurt anything in the build itself. I have not updated or installed anything recently that could account for this.

 
Archiving artifacts
FATAL: null
java.lang.NullPointerException
at hudson.model.RunParameterDefinition.getDefaultParameterValue(RunParameterDefinition.java:174)
at jenkins.model.ParameterizedJobMixIn.getDefaultParametersValues(ParameterizedJobMixIn.java:171)
at jenkins.model.ParameterizedJobMixIn.scheduleBuild2(ParameterizedJobMixIn.java:153)
at jenkins.model.ParameterizedJobMixIn.scheduleBuild2(ParameterizedJobMixIn.java:122)
at jenkins.model.ParameterizedJobMixIn$ParameterizedJob.scheduleBuild2(ParameterizedJobMixIn.java:417)
at hudson.model.AbstractProject.scheduleBuild2(AbstractProject.java:852)
at hudson.model.AbstractProject.scheduleBuild2(AbstractProject.java:824)
at hudson.model.AbstractProject.scheduleBuild2(AbstractProject.java:807)
at hudson.model.AbstractProject.scheduleBuild(AbstractProject.java:795)
at hudson.tasks.BuildTrigger.execute(BuildTrigger.java:278)
at hudson.model.AbstractBuild$AbstractBuildExecution.cleanUp(AbstractBuild.java:643)
at hudson.model.Build$BuildExecution.cleanUp(Build.java:201)
at hudson.model.Run.execute(Run.java:1784)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
at hudson.model.ResourceController.execute(ResourceController.java:97)
at hudson.model.Executor.run(Executor.java:421)
Finished: SUCCESS