The following error message is correct, but the stack trace should not be shown.

11:35 | INFO  | Build log                      - Execute strj -i /Users/oracle/Documents/workspaces/OBIEE/com.oracle.obiee.expressions/trans/obiee_expressions.str -o /Users/oracle/Documents/workspaces/OBIEE/com.oracle.obiee.expressions/target/metaborg/stratego.ctree -p com.oracle.obiee.expressions.trans --library --clean -I /Users/oracle/Documents/workspaces/OBIEE/com.oracle.obiee.expressions/src-gen -I /Users/oracle/Documents/workspaces/OBIEE/com.oracle.obiee.expressions -I /Users/oracle/Documents/workspaces/OBIEE/com.oracle.obiee.expressions/trans -I "/Users/oracle/Applications/Spoofax 2.0 (oracle).app/Contents/Eclipse/plugins/org.metaborg.meta.lib.analysis.eclipse_2.0.0.20160701-074619-master/target/unpacked/latest/trans" --cache-dir /Users/oracle/Documents/workspaces/OBIEE/com.oracle.obiee.expressions/target/stratego-cache -la stratego-lib -la stratego-sglr -la stratego-gpp -la stratego-xtc -la stratego-aterm -la stratego-sdf -la strc -F
11:35 | INFO  | stderr                         - [ strj | error ] module signatures/OBIEE-expresssions-sig not found
11:35 | INFO  | stderr                         - [ strj | error ]     imported from file /Users/oracle/Documents/workspaces/OBIEE/com.oracle.obiee.expressions/trans/outline.str
11:35 | INFO  | stderr                         - [ strj | error ] 
11:35 | ERROR | o.m.s.e.m.b.CompileBuilder     - Exception thrown during build
org.metaborg.core.MetaborgException: Rebuilding failed.
	at org.metaborg.spoofax.meta.core.build.LanguageSpecBuilder.compile(LanguageSpecBuilder.java:138) ~[org.metaborg.spoofax.meta.core_2.0.0.20160701-074619-master.jar:na]
	at org.metaborg.spoofax.eclipse.meta.build.CompileBuilder$1.run(CompileBuilder.java:49) ~[org.metaborg.spoofax.eclipse.meta_2.0.0.20160701-074619-master.jar:na]
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2241) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.metaborg.spoofax.eclipse.meta.build.CompileBuilder.build(CompileBuilder.java:69) [org.metaborg.spoofax.eclipse.meta_2.0.0.20160701-074619-master.jar:na]
	at org.metaborg.spoofax.eclipse.meta.build.Builder.build(Builder.java:53) [org.metaborg.spoofax.eclipse.meta_2.0.0.20160701-074619-master.jar:na]
	at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:734) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42) [org.eclipse.equinox.common_3.7.0.v20150402-1709.jar:na]
	at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:205) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:245) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:300) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42) [org.eclipse.equinox.common_3.7.0.v20150402-1709.jar:na]
	at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:303) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:359) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:382) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.core.internal.resources.Workspace.buildInternal(Workspace.java:486) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.core.internal.resources.Workspace.build(Workspace.java:405) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.ui.actions.BuildAction$1.runInWorkspace(BuildAction.java:287) [org.eclipse.ui.ide_3.11.0.v20150825-2158.jar:na]
	at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:39) [org.eclipse.core.resources_3.10.1.v20150725-1910.jar:na]
	at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55) [org.eclipse.core.jobs_3.7.0.v20150330-2103.jar:na]
Caused by: build.pluto.builder.RequiredBuilderFailed: Required builder failed. Error occurred in build step "Compile Stratego code": java.lang.Error: Builder failed
	at build.pluto.builder.RequiredBuilderFailed.getCause(RequiredBuilderFailed.java:37) ~[pluto-1.9.1.jar:na]
	at build.pluto.builder.BuildManager.requireInitially(BuildManager.java:258) ~[pluto-1.9.1.jar:na]
	at build.pluto.builder.BuildManagers.build(BuildManagers.java:72) ~[pluto-1.9.1.jar:na]
	at org.metaborg.spoofax.meta.core.build.LanguageSpecBuilder.plutoBuild(LanguageSpecBuilder.java:292) ~[org.metaborg.spoofax.meta.core_2.0.0.20160701-074619-master.jar:na]
	at org.metaborg.spoofax.meta.core.build.LanguageSpecBuilder.compile(LanguageSpecBuilder.java:133) ~[org.metaborg.spoofax.meta.core_2.0.0.20160701-074619-master.jar:na]
	... 18 common frames omitted
11:35 | ERROR | o.m.s.e.m.b.CompileBuilder     - BUILD FAILED

Eclipse: org.eclipse.platform.ide 4.5.2.M20160212-1500
Spoofax: org.metaborg.spoofax.eclipse 2.0.0.20160701-074619-master
System: Mac OS X x86_64 10.11.5

Submitted by Guido Wachsmuth on 1 July 2016 at 11:37

This should be solved now.