diff mbox series

[Ada] Error in Big_Real comparison

Message ID 20201127091800.GA63074@adacore.com
State New
Headers show
Series [Ada] Error in Big_Real comparison | expand

Commit Message

Pierre-Marie de Rodat Nov. 27, 2020, 9:18 a.m. UTC 
The code would incorrectly compare using absolute values, which was a
left over for another implementation incorrectly carried over.

Tested on x86_64-pc-linux-gnu, committed on trunk

gcc/ada/

	* libgnat/a-nbnbre.adb ("=", "<"): Fix.
diff mbox series

Patch

diff --git a/gcc/ada/libgnat/a-nbnbre.adb b/gcc/ada/libgnat/a-nbnbre.adb
--- a/gcc/ada/libgnat/a-nbnbre.adb
+++ b/gcc/ada/libgnat/a-nbnbre.adb
@@ -29,8 +29,6 @@ 
 --                                                                          --
 ------------------------------------------------------------------------------
 
---  This is the default version of this package, based on Big_Integers only.
-
 with Ada.Strings.Text_Output.Utils;
 with System.Img_Real; use System.Img_Real;
 
@@ -85,14 +83,16 @@  package body Ada.Numerics.Big_Numbers.Big_Reals is
    ---------
 
    function "=" (L, R : Valid_Big_Real) return Boolean is
-     (abs L.Num = abs R.Num and then L.Den = R.Den);
+     (L.Num = R.Num and then L.Den = R.Den);
 
    ---------
    -- "<" --
    ---------
 
    function "<" (L, R : Valid_Big_Real) return Boolean is
-     (abs L.Num * R.Den < abs R.Num * L.Den);
+     (L.Num * R.Den < R.Num * L.Den);
+   --  The denominator is guaranteed to be positive since Normalized is
+   --  always called when constructing a Valid_Big_Real
 
    ----------
    -- "<=" --