Macros_1.scala:14: error: macro implementation has wrong shape:
 required: (x: Impls.this.c.Expr[Int]): Impls.this.c.Expr[Any]
 or      : (x: Impls.this.c.Tree): Impls.this.c.Tree
 found   : (x: Impls.this.c.universe.Block): Impls.this.c.Tree
type mismatch for parameter x: Impls.this.c.Expr[Int] does not conform to Impls.this.c.universe.Block
  def m3(x: Int) = macro Impls.impl3
      ^
one error found