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5 <title>Petter Reinholdtsen: Two projects that have improved the quality of free software a lot
</title>
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12 <a href=
"http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen
</a>
20 <div class=
"title">Two projects that have improved the quality of free software a lot
</div>
21 <div class=
"date">2009-
05-
02 15:
00</div>
23 <p>There are two software projects that have had huge influence on the
24 quality of free software, and I wanted to mention both in case someone
25 do not yet know them.
</p>
27 <p>The first one is
<a href=
"http://valgrind.org/">valgrind
</a>, a
28 tool to detect and expose errors in the memory handling of programs.
29 It is easy to use, all one need to do is to run 'valgrind program',
30 and it will report any problems on stdout. It is even better if the
31 program include debug information. With debug information, it is able
32 to report the source file name and line number where the problem
33 occurs. It can report things like 'reading past memory block in file
34 X line N, the memory block was allocated in file Y, line M', and
35 'using uninitialised value in control logic'. This tool has made it
36 trivial to investigate reproducible crash bugs in programs, and have
37 reduced the number of this kind of bugs in free software a lot.
40 <a href=
"http://en.wikipedia.org/wiki/Coverity">Coverity
</a> which is
41 a source code checker. It is able to process the source of a program
42 and find problems in the logic without running the program. It
43 started out as the Stanford Checker and became well known when it was
44 used to find bugs in the Linux kernel. It is now a commercial tool
45 and the company behind it is running
46 <a href=
"http://www.scan.coverity.com/">a community service
</a> for the
47 free software community, where a lot of free software projects get
48 their source checked for free. Several thousand defects have been
49 found and fixed so far. It can find errors like 'lock L taken in file
50 X line N is never released if exiting in line M', or 'the code in file
51 Y lines O to P can never be executed'. The projects included in the
52 community service project have managed to get rid of a lot of
53 reliability problems thanks to Coverity.
</p>
55 <p>I believe tools like this, that are able to automatically find
56 errors in the source, are vital to improve the quality of software and
57 make sure we can get rid of the crashing and failing software we are
58 surrounded by today.
</p>
61 <div class=
"tags">Tags:
<a href=
"http://people.skolelinux.org/pere/blog/tags/debian">debian
</a>,
<a href=
"http://people.skolelinux.org/pere/blog/tags/english">english
</a>.
</div>
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