diff --git a/core-macros/src/main/scala/sbt/internal/util/appmacro/ContextUtil.scala b/core-macros/src/main/scala/sbt/internal/util/appmacro/ContextUtil.scala
index 4bec6e63d..1a4658813 100644
--- a/core-macros/src/main/scala/sbt/internal/util/appmacro/ContextUtil.scala
+++ b/core-macros/src/main/scala/sbt/internal/util/appmacro/ContextUtil.scala
@@ -312,6 +312,16 @@ final class ContextUtil[C <: blackbox.Context](val ctx: C) {
               case Converted.Failure(p, m)       => ctx.abort(p, m)
               case _: Converted.NotApplicable[_] => super.transform(tree)
             }
+          // try to workaround https://github.com/scala/bug/issues/12112 by removing raw Ident(_) in blocks
+          case Block(stats0, expr0) =>
+            val stats = stats0 flatMap { stat0 =>
+              val stat = super.transform(stat0)
+              stat match {
+                case Typed(ident @ Ident(_), _) if ident.symbol.isSynthetic => None
+                case _                                                      => Some(stat)
+              }
+            }
+            Block(stats, super.transform(expr0))
           case _ => super.transform(tree)
         }
     }
diff --git a/core-macros/src/main/scala/sbt/internal/util/appmacro/Instance.scala b/core-macros/src/main/scala/sbt/internal/util/appmacro/Instance.scala
index 5c15a3346..f077ed5ab 100644
--- a/core-macros/src/main/scala/sbt/internal/util/appmacro/Instance.scala
+++ b/core-macros/src/main/scala/sbt/internal/util/appmacro/Instance.scala
@@ -187,9 +187,7 @@ object Instance {
       qual.foreach(checkQual)
       val vd = util.freshValDef(tpe, qual.pos, functionSym)
       inputs ::= new Input(tpe, qual, vd)
-      // try to workaround https://github.com/scala/bug/issues/12112 by calling Predef.identity(...)
-      val rv = util.refVal(selection, vd)
-      q"scala.Predef.identity[$tpe]($rv: $tpe)"
+      util.refVal(selection, vd)
     }
     def sub(name: String, tpe: Type, qual: Tree, replace: Tree): Converted[c.type] = {
       val tag = c.WeakTypeTag[T](tpe)