Replace Throwable catches with NonFatal

Previously, stackoverflows led to infinite loops because the catch
immediately threw another stack overflow. Anyway, one should never
catch Throwable.

4 files changed, 7 insertions, 4 deletions

diff --git a/src/dotty/tools/dotc/core/Denotations.scala b/src/dotty/tools/dotc/core/Denotations.scala
index 236bdb7f4..cd585dea1 100644
--- a/src/dotty/tools/dotc/core/Denotations.scala
+++ b/src/dotty/tools/dotc/core/Denotations.scala
@@ -386,7 +386,7 @@ object Denotations {
         case info: MethodicType =>
           try info.signature
           catch { // !!! DEBUG
-            case ex: Throwable =>
+            case scala.util.control.NonFatal(ex) =>
               println(s"cannot take signature of ${info.show}")
               throw ex
           }
diff --git a/src/dotty/tools/dotc/core/SymbolLoaders.scala b/src/dotty/tools/dotc/core/SymbolLoaders.scala
index 886c728b7..76ba3885e 100644
--- a/src/dotty/tools/dotc/core/SymbolLoaders.scala
+++ b/src/dotty/tools/dotc/core/SymbolLoaders.scala
@@ -14,6 +14,7 @@ import Contexts._, Symbols._, Flags._, SymDenotations._, Types._, Scopes._, util
 import StdNames._, NameOps._
 import Decorators.{StringDecorator, StringInterpolators}
 import pickling.ClassfileParser
+import scala.util.control.NonFatal
 
 object SymbolLoaders {
   /** A marker trait for a completer that replaces the original
@@ -206,7 +207,7 @@ abstract class SymbolLoader extends LazyType {
     } catch {
       case ex: IOException =>
         signalError(ex)
-      case ex: Throwable =>
+      case NonFatal(ex) =>
         println(s"exception caught when loading $root: $ex")
         throw ex
     } finally {
diff --git a/src/dotty/tools/dotc/core/TypeComparer.scala b/src/dotty/tools/dotc/core/TypeComparer.scala
index 42af31553..076015d99 100644
--- a/src/dotty/tools/dotc/core/TypeComparer.scala
+++ b/src/dotty/tools/dotc/core/TypeComparer.scala
@@ -12,6 +12,7 @@ import util.{Stats, DotClass, SimpleMap}
 import config.Config
 import config.Printers._
 import TypeErasure.{erasedLub, erasedGlb}
+import scala.util.control.NonFatal
 
 /** Provides methods to compare types.
  */
@@ -401,7 +402,7 @@ class TypeComparer(initctx: Context) extends DotClass {
 
         result
       } catch {
-        case ex: Throwable =>
+        case NonFatal(ex) =>
           def showState =  {
             println(disambiguated(implicit ctx => s"assertion failure for ${tp1.show} <:< ${tp2.show}, frozen = $frozenConstraint"))
             def explainPoly(tp: Type) = tp match {
diff --git a/src/dotty/tools/dotc/core/pickling/ClassfileParser.scala b/src/dotty/tools/dotc/core/pickling/ClassfileParser.scala
index f92573d22..8231c25af 100644
--- a/src/dotty/tools/dotc/core/pickling/ClassfileParser.scala
+++ b/src/dotty/tools/dotc/core/pickling/ClassfileParser.scala
@@ -13,6 +13,7 @@ import scala.collection.mutable.{ ListBuffer, ArrayBuffer }
 import scala.annotation.switch
 import typer.Checking.checkNonCyclic
 import io.AbstractFile
+import scala.util.control.NonFatal
 
 class ClassfileParser(
     classfile: AbstractFile,
@@ -447,7 +448,7 @@ class ClassfileParser(
     else Some(Annotation.deferredResolve(attrType, argbuf.toList))
   } catch {
     case f: FatalError => throw f // don't eat fatal errors, they mean a class was not found
-    case ex: Throwable =>
+    case NonFatal(ex) =>
       // We want to be robust when annotations are unavailable, so the very least
       // we can do is warn the user about the exception
       // There was a reference to ticket 1135, but that is outdated: a reference to a class not on