Copied from Debian.

From: Rodeo
Origin: https://github.com/HandBrake/HandBrake/blob/master/contrib/a52dec/A04-modern-gcc-cflags.patch

--- a52dec-0.7.4/configure.in.orig
+++ a52dec-0.7.4/configure.in
@@ -34,11 +34,11 @@
     case "$host" in
     i?86-* | k?-*)
 	case "$host" in
-	i386-*) OPT_CFLAGS="$CFLAGS -mcpu=i386";;
-	i486-*) OPT_CFLAGS="$CFLAGS -mcpu=i486";;
-	i586-*) OPT_CFLAGS="$CFLAGS -mcpu=pentium";;
-	i686-*) OPT_CFLAGS="$CFLAGS -mcpu=pentiumpro";;
-	k6-*)   OPT_CFLAGS="$CFLAGS -mcpu=k6";;
+	i386-*) OPT_CFLAGS="$CFLAGS -mtune=i386";;
+	i486-*) OPT_CFLAGS="$CFLAGS -mtune=i486";;
+	i586-*) OPT_CFLAGS="$CFLAGS -mtune=pentium";;
+	i686-*) OPT_CFLAGS="$CFLAGS -mtune=pentiumpro";;
+	k6-*)   OPT_CFLAGS="$CFLAGS -mtune=k6";;
 	esac
 	AC_TRY_CFLAGS([$OPT_CFLAGS],[CFLAGS=$OPT_CFLAGS]);;
     sparc-* | sparc64-*)
</option>
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<tr><td class='sub'>Wojtek's customized Guix</td><td class='sub right'></td></tr></table>
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<div class='path'>path: <a href='/guix/log/?id=d5f89c0b938fdfb82639db70a4a1c135e993ea49'>root</a>/<a href='/guix/log/gnu?id=d5f89c0b938fdfb82639db70a4a1c135e993ea49'>gnu</a>/<a href='/guix/log/gnu/packages?id=d5f89c0b938fdfb82639db70a4a1c135e993ea49'>packages</a>/<a href='/guix/log/gnu/packages/rsync.scm?id=d5f89c0b938fdfb82639db70a4a1c135e993ea49'>rsync.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/rsync.scm?id=d5f89c0b938fdfb82639db70a4a1c135e993ea49&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-09-23 18:17:15 +0200'>2021-09-23</span></td><td><a href='/guix/commit/gnu/packages/rsync.scm?id=6b035ad2fa028d923ea09c8e2a363b318df91538'>gnu: rsync: Enable zstd &amp; lz4 compression.</a><span class='msg-avail'>...<span class='msg-tooltip'>Both are ridiculously more suited to this role than the old zlib
compressor.  The closure size increase is negligible (1 MiB or 1.3% for
zstd, 1.7 MiB for both).

* gnu/packages/rsync.scm (rsync-next)[inputs]: Add zstd:lib and lz4.
[arguments]: Remove the corresponding "--disable-zstd" and
"--disable-lz4" #:configure-flags.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2021-05-25 16:32:52 -0400'>2021-05-25</span></td><td><a href='/guix/commit/gnu/packages/rsync.scm?id=458126a2370706a35cf6a272b2c7a988c75ab375'>gnu: Add rsync 3.2.3.</a><span class='msg-avail'>...<span class='msg-tooltip'>*  gnu/packages/rsync.scm (rsync-next): New variable.
</span></span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2021-04-11 18:07:39 +0200'>2021-04-11</span></td><td><a href='/guix/commit/gnu/packages/rsync.scm?id=96feb7515e3c75e7e8e5f51d91a3c6d1bf1c36f1'>gnu: librsync: Update to 2.3.2.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/rsync.scm (librsync): Update to 2.3.2.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>