https://github.com/jenkinsci/git-parameter-plugin/pull/17#issuecomment-208865040

Jenkins LTS here (1.642.4), we get:

Caused by: java.lang.NullPointerException
at java.util.regex.Pattern.<init>(Pattern.java:1350)
at java.util.regex.Pattern.compile(Pattern.java:1028)
at net.uaznia.lukanus.hudson.plugins.gitparameter.GitParameterDefinition.generateContents(GitParameterDefinition.java:313)
at net.uaznia.lukanus.hudson.plugins.gitparameter.GitParameterDefinition$DescriptorImpl.doFillValueItems(GitParameterDefinition.java:399)
definition is:

gitParam('GIT_BRANCH')

{ description('git branch to build') type('BRANCH') defaultValue('origin/dev/*') }