Workaround for SI-5583.

Somehow type args to be applied arrive in the specialized subclass
where type args are no longer applicable.  Log and discard.

Author: paulp

src/compiler/scala/tools/nsc/transform/SpecializeTypes.scala

@@ -1327,7 +1327,7 @@ abstract class SpecializeTypes extends InfoTransform with TypingTransformers {
             }
           } else super.transform(tree)
 
-        case TypeApply(Select(qual, name), targs)
+        case TypeApply(sel @ Select(qual, name), targs)
                 if (!specializedTypeVars(symbol.info).isEmpty && name != nme.CONSTRUCTOR) =>
           debuglog("checking typeapp for rerouting: " + tree + " with sym.tpe: " + symbol.tpe + " tree.tpe: " + tree.tpe)
           val qual1 = transform(qual)
@@ -1341,14 +1341,22 @@ abstract class SpecializeTypes extends InfoTransform with TypingTransformers {
               val residualTargs = symbol.info.typeParams zip targs collect {
                 case (tvar, targ) if !env.contains(tvar) || !isPrimitiveValueClass(env(tvar).typeSymbol) => targ
               }
+              if (specMember.info.typeParams.isEmpty) {
+                // See SI-5583.  Don't know why it happens now if it didn't before.
+                if (residualTargs.nonEmpty)
+                  log("!!! Type args to be applied, but symbol says no parameters: " + ((specMember.defString, residualTargs)))
 
-              ifDebug(assert(residualTargs.length == specMember.info.typeParams.length,
-                "residual: %s, tparams: %s, env: %s".format(residualTargs, symbol.info.typeParams, env))
-              )
+                localTyper.typed(sel)
+              }
+              else {
+                ifDebug(assert(residualTargs.length == specMember.info.typeParams.length,
+                  "residual: %s, tparams: %s, env: %s".format(residualTargs, specMember.info.typeParams, env))
+                )
 
-              val tree1 = gen.mkTypeApply(Select(qual1, specMember), residualTargs)
-              debuglog("rewrote " + tree + " to " + tree1)
-              localTyper.typedOperator(atPos(tree.pos)(tree1)) // being polymorphic, it must be a method
+                val tree1 = gen.mkTypeApply(Select(qual1, specMember), residualTargs)
+                debuglog("rewrote " + tree + " to " + tree1)
+                localTyper.typedOperator(atPos(tree.pos)(tree1)) // being polymorphic, it must be a method
+              }
 
             case None => super.transform(tree)
           }

test/files/run/t5583.check

@@ -0,0 +1,20 @@
+Type in expressions to have them evaluated.
+Type :help for more information.
+
+scala> 
+
+scala> var s = 0
+s: Int = 0
+
+scala> for (i <- 1 to 10) {s += i}
+
+scala> for (i <- 1 to 10) {s += i}
+
+scala> for (i <- 1 to 10) {s += i}
+
+scala> println(s)
+165
+
+scala> 
+
+scala> 

test/files/run/t5583.scala

@@ -0,0 +1,11 @@
+import scala.tools.partest.ReplTest
+
+object Test extends ReplTest {
+  def code = """
+var s = 0
+for (i <- 1 to 10) {s += i}
+for (i <- 1 to 10) {s += i}
+for (i <- 1 to 10) {s += i}
+println(s)
+  """
+}