Merge pull request #425 in G/fastr from ~LUKAS.STADLER_ORACLE.COM/fastr:small_changes to master

* commit '680e7f49':
  run gate tests on "fast" machines
  output stack traces when unit tests time out

ci.hocon

@@ -136,8 +136,8 @@ rbcheck : ${common} {
 # The standard set of gate builds. N.B. the style/builtin checks are only run on Linux as they are not OS-dependent.
 
 builds = [
-  ${gateTestLinux}            {capabilities : [linux, amd64],  targets : [gate, post-merge], name: "gate-test-linux-amd64"}
-  ${gateTestNoSpecialsLinux}  {capabilities : [linux, amd64],  targets : [gate, post-merge], name: "gate-test-linux-amd64-nospecials"}
+  ${gateTestLinux}            {capabilities : [linux, amd64, fast],  targets : [gate, post-merge], name: "gate-test-linux-amd64"}
+  ${gateTestNoSpecialsLinux}  {capabilities : [linux, amd64, fast],  targets : [gate, post-merge], name: "gate-test-linux-amd64-nospecials"}
   ${gateTestDarwin}           {capabilities : [darwin, amd64], targets : [gate, post-merge], name: "gate-test-darwin-amd64"}
   ${gateStyle}                {capabilities : [linux, amd64],  targets : [gate, post-merge], name: "gate-style-linux-amd64"}
   ${rbcheck}                  {capabilities : [linux, amd64],  targets : [gate, post-merge], name: "gate-rbcheck-linux-amd64"}

com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/generate/FastRSession.java

@@ -207,6 +207,9 @@ public final class FastRSession implements RSession {
         try {
             if (!thread.await(longTimeout ? longTimeoutValue : timeoutValue)) {
                 consoleHandler.println("<timeout>");
+                for (StackTraceElement element : thread.getStackTrace()) {
+                    System.out.println(element);
+                }
                 thread.stop();
                 evalThread.ensureContextDestroyed();
                 evalThread = null;