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='2021-07-29 19:57:57 +0200'>2021-07-29</span></td><td><a href='/guix/commit/gnu/packages/php.scm?id=c022c1e5b23b9916264c3b4b8e13f623a14ddaaf'>gnu: php: Update to 7.4.22 [security fixes].</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/php.scm (php): Update to 7.4.22.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2021-07-23 17:29:34 +0200'>2021-07-23</span></td><td><a href='/guix/commit/gnu/packages/php.scm?id=379bb236d44abb93f490115cf26800eb4dc25b2d'>gnu: php: Update to 7.4.21.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/php.scm (php): Update to 7.4.21.
[arguments]: Remove trailing #t's.
[native-inputs]: Remove INTLTOOL. Add GETTEXT-MINIMAL.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2021-06-26 22:46:09 +0200'>2021-06-26</span></td><td><a href='/guix/commit/gnu/packages/php.scm?id=68e378913914f35e40b05108c709f4d1eb55b18a'>gnu: php: Build sodium.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/php.scm (php): Build sodium extension.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Aljosha Papsch</td></tr>