From eb79135b976114e75526a0d5b37401f110d47136 Mon Sep 17 00:00:00 2001
From: Martin Odersky <odersky@gmail.com>
Date: Mon, 14 Aug 2006 16:40:46 +0000
Subject: Fixed bug 697

---
 src/compiler/scala/tools/nsc/ast/parser/Parsers.scala     |  4 ++--
 src/compiler/scala/tools/nsc/symtab/Constants.scala       |  3 +++
 .../scala/tools/nsc/typechecker/ConstantFolder.scala      | 15 +++++++++------
 3 files changed, 14 insertions(+), 8 deletions(-)

(limited to 'src')

diff --git a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
index 6fe085a54e..b942f73b22 100644
--- a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
+++ b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
@@ -273,8 +273,8 @@ trait Parsers requires SyntaxAnalyzer {
             case '|'             => 2
             case '^'             => 3
             case '&'             => 4
-            case '<' | '>'       => 5
-            case '=' | '!'       => 6
+            case '=' | '!'       => 5
+            case '<' | '>'       => 6
             case ':'             => 7
             case '+' | '-'       => 8
             case '*' | '/' | '%' => 9
diff --git a/src/compiler/scala/tools/nsc/symtab/Constants.scala b/src/compiler/scala/tools/nsc/symtab/Constants.scala
index 38fc822b18..181ab56ef1 100644
--- a/src/compiler/scala/tools/nsc/symtab/Constants.scala
+++ b/src/compiler/scala/tools/nsc/symtab/Constants.scala
@@ -12,6 +12,7 @@ trait Constants requires SymbolTable {
 
   import definitions._;
 
+  final val NoTag      = LITERAL - LITERAL
   final val UnitTag    = LITERALunit - LITERAL;
   final val BooleanTag = LITERALboolean - LITERAL;
   final val ByteTag    = LITERALbyte - LITERAL;
@@ -27,6 +28,8 @@ trait Constants requires SymbolTable {
   final val EnumTag    = ClassTag + 1;
   final val ArrayTag   = EnumTag + 1;
 
+  def isNumeric(tag: int) = ByteTag <= tag && tag <= DoubleTag
+
   case class Constant(value: Any) {
 
     val tag: int =
diff --git a/src/compiler/scala/tools/nsc/typechecker/ConstantFolder.scala b/src/compiler/scala/tools/nsc/typechecker/ConstantFolder.scala
index 32d7fcd800..a19c5799d4 100644
--- a/src/compiler/scala/tools/nsc/typechecker/ConstantFolder.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/ConstantFolder.scala
@@ -16,21 +16,21 @@ abstract class ConstantFolder {
     case Apply(Select(Literal(x), op), List(Literal(y))) => foldBinop(op, x, y)
     case Select(Literal(x), op) => foldUnop(op, x)
     case _ => null
-  });
+  })
 
   /** If tree is a constant value that can be converted to type `pt', perform the conversion */
   def apply(tree: Tree, pt: Type): Tree = fold(tree, tree.tpe match {
     case ConstantType(x) => x convertTo pt
     case _ => null
-  });
+  })
 
-  private def fold(tree: Tree, compX: =>Constant): Tree =
+  private def fold(tree: Tree, compX: => Constant): Tree =
     try {
       val x = compX
       if (x != null && x.tag != UnitTag) tree setType ConstantType(x)
-      else tree;
+      else tree
     } catch {
-      case _:ArithmeticException => tree   // the code will crash at runtime,
+      case _: ArithmeticException => tree   // the code will crash at runtime,
 	                                   // but that is better than the
                                            // compiler itself crashing
     }
@@ -55,7 +55,10 @@ abstract class ConstantFolder {
   }
 
   private def foldBinop(op: Name, x: Constant, y: Constant): Constant = try {
-    val optag = if (x.tag > y.tag) x.tag else y.tag;
+    val optag = if (x.tag == y.tag) x.tag
+                else if (isNumeric(x.tag) && isNumeric(y.tag))
+                  if (x.tag > y.tag) x.tag else y.tag
+                else NoTag
     optag match {
       case BooleanTag =>
 	op match {
-- 
cgit v1.2.3