sjavac test fails when assertions enabled

jtreg -va test/tools/sjavac/
...

Caused by: java.lang.AssertionError
at com.sun.tools.sjavac.server.PortFile.getPort(PortFile.java:134)
at com.sun.tools.sjavac.server.JavacServer.connectAndCompile(JavacServer.java:467)
at com.sun.tools.sjavac.server.JavacServer.useServer(JavacServer.java:299)
at com.sun.tools.sjavac.server.JavacServer.connectGetSysInfo(JavacServer.java:438)
at com.sun.tools.sjavac.CompileJavaPackages.transform(CompileJavaPackages.java:95)
at com.sun.tools.sjavac.JavacState.perform(JavacState.java:719)
at com.sun.tools.sjavac.JavacState.performJavaCompilations(JavacState.java:667)
at com.sun.tools.sjavac.Main.go(Main.java:330)
at SJavac.compile(SJavac.java:433)
at SJavac.initialCompile(SJavac.java:131)
at SJavac.test(SJavac.java:75)
at SJavac.main(SJavac.java:38)
... 11 more