Fix a bug whereby 'mformat' could end up passing uninitialized bytes
to write(2).  This could be reproduced with:

  mformat -C -f 1440 -L 16  -N 77777777 -i  /tmp/x ::

where the output of /tmp/x would be non-deterministic.

Patch by Ludovic Courtès <ludo@gnu.org>.

--- mtools-4.0.23/mformat.c	2019-04-21 00:12:01.496116195 +0200
+++ mtools-4.0.23/mformat.c	2019-04-21 00:12:36.675967157 +0200
@@ -927,6 +927,7 @@ void mformat(int argc, char **argv, int
 	
 	char *endptr;
 
+	memset(&boot.bytes, '\0', sizeof boot);
 	hs = hs_set = 0;
 	argtracks = 0;
 	argheads = 0;

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<tr><td><span title='2023-07-22 11:29:31 +0800'>2023-07-22</span></td><td><a href='/guix/commit/gnu/packages/perl-check.scm?id=fb52f687f79fb74f724abd1835e18bad6a2901e6'>gnu: Add perl-test-inter.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/perl-check.scm (perl-test-inter): New variable.

Signed-off-by: 宋文武 &lt;iyzsong@member.fsf.org&gt;
</span></span></td><td>Rikard Nordgren</td></tr>
<tr><td><span title='2022-11-20 17:19:59 +0100'>2022-11-20</span></td><td><a href='/guix/commit/gnu/packages/perl-check.scm?id=046d9655a3a8bb5f98fe963fe3736b4045a37fb5'>gnu: perl-test-fatal: Update to 0.016.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/perl-check.scm (perl-test-fatal): Update to 0.016.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2022-08-12 23:40:33 +0300'>2022-08-12</span></td><td><a href='/guix/commit/gnu/packages/perl-check.scm?id=c20a61a8aba3e1de1af7590ee321f22bcd715ed0'>gnu: perl-test-simple: Update to 1.302191.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/perl-check.scm (perl-test-simple): Update to 1.302191.
</span></span></td><td>Efraim Flashner</td></tr>
 South</td></tr>
<tr><td><span title='2021-12-13 17:48:25 +0100'>2021-12-13</span></td><td><a href='/guix/commit/gnu/packages/lighting.scm?id=8394619baceb118df92e355377fd543bb1aa501a'>gnu: Simplify package inputs.</a><span class='msg-avail'>...<span class='msg-tooltip'>This commit was obtained by running:

  ./pre-inst-env guix style

without any additional argument.
</span></span></td><td>Ludovic Courtès</td></tr>