From ac22346b43562c08625ed4a0b56cd6751d97ec83 Mon Sep 17 00:00:00 2001
From: Rune Zedeler <rune@lilypond.org>
Date: Tue, 23 Oct 2007 06:26:35 +0200
Subject: [PATCH] Bugfix: Rational.cc: Modulo and trunc did not work with
 negative numbers.

This is a library fix that did not show any bugs in lilypond - because
lilypond does not use modulus of negative rationals.
---
 flower/rational.cc | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/flower/rational.cc b/flower/rational.cc
index 724f0d99ca..4205b1d683 100644
--- a/flower/rational.cc
+++ b/flower/rational.cc
@@ -50,7 +50,9 @@ Rational::abs () const
 Rational
 Rational::trunc_rat () const
 {
-  return Rational (num_ - (num_ % den_), den_);
+  if (is_infinity())
+    return *this;
+  return Rational ((num_ - (num_ % den_)) * sign_, den_);
 }
 
 Rational::Rational ()
@@ -79,6 +81,7 @@ void
 Rational::set_infinite (int s)
 {
   sign_ = ::sign (s) * 2;
+  num_ = 1;
 }
 
 Rational
-- 
2.39.2