Based on (hunk for changelog removed)
From b62c902dd258125cac86cd2df21fc898035a43d3 Mon Sep 17 00:00:00 2001
From: Michael Pruett <michael@68k.org>
Date: Mon, 29 Aug 2016 23:08:26 -0500
Subject: [PATCH] Fix undefined behavior in sign conversion.


---
 ChangeLog                           | 5 +++++
 libaudiofile/modules/SimpleModule.h | 3 ++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/libaudiofile/modules/SimpleModule.h b/libaudiofile/modules/SimpleModule.h
index 03c6c69..bad85ad 100644
--- a/libaudiofile/modules/SimpleModule.h
+++ b/libaudiofile/modules/SimpleModule.h
@@ -123,7 +123,8 @@ struct signConverter
 	typedef typename IntTypes<Format>::UnsignedType UnsignedType;
 
 	static const int kScaleBits = (Format + 1) * CHAR_BIT - 1;
-	static const int kMinSignedValue = -1 << kScaleBits;
+	static const int kMaxSignedValue = (((1 << (kScaleBits - 1)) - 1) << 1) + 1;
+	static const int kMinSignedValue = -kMaxSignedValue - 1;
 
 	struct signedToUnsigned : public std::unary_function<SignedType, UnsignedType>
 	{
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<tr><td><span title='2017-01-04 00:00:34 -0500'>2017-01-04</span></td><td><a href='/guix/commit/gnu/packages/ebook.scm?id=37e8a2e219b21a43f80e9cf8581db1b1e2f67105'>gnu: calibre: Update to 2.76.0.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ebook.scm (calibre): Update to 2.76.0.

Signed-off-by: Leo Famulari &lt;leo@famulari.name&gt;
</span></span></td><td>Alex Griffin</td></tr>
<tr><td><span title='2016-12-12 16:14:30 +0200'>2016-12-12</span></td><td><a href='/guix/commit/gnu/packages/ebook.scm?id=987ad88fb6d6b133e5f4bf499610700336d1dd07'>gnu: calibre: Update to 2.74.0.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ebook.scm (calibre): Update to 2.74.0.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2016-12-12 16:14:29 +0200'>2016-12-12</span></td><td><a href='/guix/commit/gnu/packages/ebook.scm?id=c5ea912016fdba6a1debe6eef7fbd51e59efb9a5'>gnu: calibre: Update qt dependancies.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ebook.scm (calibre)[native-inputs]: Remove qt, add
qtbase.
[inputs]: Remove qt, replace python2-pyqt@5.5 with python2-pyqt.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2016-12-02 18:07:36 +0100'>2016-12-02</span></td><td><a href='/guix/commit/gnu/packages/ebook.scm?id=e89aceab635ad053244586ef430162e4817d8f64'>gnu: calibre: Do not use python setuptools for building.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ebook.scm (calibre)[arguments]: Set #:use-setuptools?
to false.
</span></span></td><td>Hartmut Goebel</td></tr>