add comments.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@42237 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/AST/Expr.h b/include/clang/AST/Expr.h
index 94c02aa..73f730e 100644
--- a/include/clang/AST/Expr.h
+++ b/include/clang/AST/Expr.h
@@ -225,7 +225,11 @@
 
   const llvm::APFloat &getValue() const { return Value; }
 
-  double getValueAsDouble() const { 
+  /// getValueAsDouble - This returns the value as an inaccurate double.  Note
+  /// that this may cause loss of precision, but is useful for debugging dumps
+  /// etc.
+  double getValueAsDouble() const {
+    // FIXME: We need something for long double here.
     if (cast<BuiltinType>(getType())->getKind() == BuiltinType::Float)
       return Value.convertToFloat();
     else