Merge pull request #798 from retronym/ticket/2807-4

SI-2807 Avoid catch all warning for Stable Id patterns

1 files changed, 3 insertions, 2 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index a167180267..52cce11deb 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -4868,9 +4868,10 @@ trait Typers extends Modes with Adaptations with Tags {
 
           for (cdef <- catches1 if cdef.guard.isEmpty) {
             def warn(name: Name) = context.warning(cdef.pat.pos, s"This catches all Throwables. If this is really intended, use `case ${name.decoded} : Throwable` to clear this warning.")
+            def unbound(t: Tree) = t.symbol == null || t.symbol == NoSymbol
             cdef.pat match {
-              case Bind(name, Ident(_)) => warn(name)
-              case Ident(name)          => warn(name)
+              case Bind(name, i@Ident(_)) if unbound(i) => warn(name)
+              case i@Ident(name) if unbound(i)          => warn(name)
               case _ =>
             }
           }