Don't create a new thread on each presentation ...

Don't create a new thread on each presentation compiler crash. Solves
race conditions in outstanding maps (should fix deadlocks in the IDE).
Added project name to the thread name and log messages. no review.

2 files changed, 18 insertions, 27 deletions

diff --git a/src/compiler/scala/tools/nsc/interactive/Global.scala b/src/compiler/scala/tools/nsc/interactive/Global.scala
index a2426d2212..ddc870a045 100644
--- a/src/compiler/scala/tools/nsc/interactive/Global.scala
+++ b/src/compiler/scala/tools/nsc/interactive/Global.scala
@@ -24,7 +24,7 @@ import scala.reflect.generic.Flags.{ACCESSOR, PARAMACCESSOR}
 
 /** The main class of the presentation compiler in an interactive environment such as an IDE
  */
-class Global(settings: Settings, reporter: Reporter)
+class Global(settings: Settings, reporter: Reporter, projectName: String = "")
   extends scala.tools.nsc.Global(settings, reporter)
      with CompilerControl
      with RangePositions
@@ -61,11 +61,11 @@ class Global(settings: Settings, reporter: Reporter)
 
   /** Print msg only when debugIDE is true. */
   @inline final def debugLog(msg: => String) =
-    if (debugIDE) println(msg)
+    if (debugIDE) println("[%s] %s".format(projectName, msg))
 
   /** Inform with msg only when verboseIDE is true. */
   @inline final def informIDE(msg: => String) =
-    if (verboseIDE) println("["+msg+"]")
+    if (verboseIDE) println("[%s][%s]".format(projectName, msg))
 
   override def forInteractive = true
 
@@ -390,9 +390,9 @@ class Global(settings: Settings, reporter: Reporter)
 
   /** Create a new presentation compiler runner.
    */
-  private[interactive] def newRunnerThread(): Thread = {
+  private def newRunnerThread(): Thread = {
     threadId += 1
-    compileRunner = new PresentationCompilerThread(this, threadId)
+    compileRunner = new PresentationCompilerThread(this, projectName)
     compileRunner.start()
     compileRunner
   }
diff --git a/src/compiler/scala/tools/nsc/interactive/PresentationCompilerThread.scala b/src/compiler/scala/tools/nsc/interactive/PresentationCompilerThread.scala
index b61d7f6638..951cba286f 100644
--- a/src/compiler/scala/tools/nsc/interactive/PresentationCompilerThread.scala
+++ b/src/compiler/scala/tools/nsc/interactive/PresentationCompilerThread.scala
@@ -8,30 +8,25 @@ package scala.tools.nsc.interactive
 /** A presentation compiler thread. This is a lightweight class, delegating most
  *  of its functionality to the compiler instance.
  *
- *  @note This thread class may not be GCd, so it's important not to keep around
- *        large objects. For instance, the JDT weaving framework keeps threads around
- *        in a map, preventing them from being GCd. This prompted the separation between
- *        interactive.Global and this class.
  */
-class PresentationCompilerThread(var compiler: Global, threadId: Int) extends Thread("Scala Presentation Compiler V"+threadId) {
+final class PresentationCompilerThread(var compiler: Global, name: String = "") extends Thread("Scala Presentation Compiler V [" + name + "]") {
+
   /** The presentation compiler loop.
    */
   override def run() {
     compiler.debugLog("starting new runner thread")
-    try {
-      while (true) {
-        compiler.checkNoResponsesOutstanding()
-        compiler.log.logreplay("wait for more work", { compiler.scheduler.waitForMoreWork(); true })
-        compiler.pollForWork(compiler.NoPosition)
-        while (compiler.isOutOfDate) {
-          try {
-            compiler.backgroundCompile()
-          } catch {
-            case FreshRunReq =>
-              compiler.debugLog("fresh run req caught, starting new pass")
-          }
-          compiler.log.flush()
+    while (true) try {
+      compiler.checkNoResponsesOutstanding()
+      compiler.log.logreplay("wait for more work", { compiler.scheduler.waitForMoreWork(); true })
+      compiler.pollForWork(compiler.NoPosition)
+      while (compiler.isOutOfDate) {
+        try {
+          compiler.backgroundCompile()
+        } catch {
+          case FreshRunReq =>
+            compiler.debugLog("fresh run req caught, starting new pass")
         }
+        compiler.log.flush()
       }
     } catch {
       case ex @ ShutdownReq =>
@@ -42,7 +37,6 @@ class PresentationCompilerThread(var compiler: Global, threadId: Int) extends Th
         compiler = null
       case ex =>
         compiler.log.flush()
-        compiler.newRunnerThread()
 
         ex match {
           case FreshRunReq =>
@@ -51,9 +45,6 @@ class PresentationCompilerThread(var compiler: Global, threadId: Int) extends Th
             compiler.debugLog("validate exception caught outside presentation compiler loop; ignored")
           case _ => ex.printStackTrace(); compiler.informIDE("Fatal Error: "+ex)
         }
-
-        // make sure we don't keep around stale instances
-        compiler = null
     }
   }
 }