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C++: Use <ol> for recommendations

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Jonas Jensen
2019-11-19 12:57:02 +01:00
parent 7d7d166113
commit 466f7fe6b2
1 changed files with 18 additions and 8 deletions
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cpp/ql/src/Likely Bugs/Arithmetic/SignedOverflowCheck.qhelp
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@@ -18,29 +18,39 @@ optimizing compiler.
<recommendation>
<p>
Solutions to this problem can be thought of as falling into one of two
categories: (1) rewrite the signed expression so that overflow cannot occur
but the signedness remains, or (2) change the variables and all their uses to
be unsigned. The following cases all fall into the first category.
categories:
</p>
<ol>
<li>Rewrite the signed expression so that overflow cannot occur
but the signedness remains.</li>
<li>Change the variables and all their uses to be unsigned.</li>
</ol>
<p>
The following cases all fall into the first category.
</p>
<ol>
<li>
Given <code>unsigned short n1, delta</code> and <code>n1 + delta &lt; n1</code>,
it is possible to rewrite it as <code>(unsigned short)(n1 + delta)&nbsp;&lt;&nbsp;n1</code>.
Note that <code>n1 + delta</code> does not actually overflow, due to <code>int</code> promotion.
</p>
</li>
<p>
<li>
Given <code>unsigned short n1, delta</code> and <code>n1 + delta &lt; n1</code>,
it is also possible to rewrite it as <code>n1 &gt; USHORT_MAX - delta</code>. The
<code>limits.h</code> or <code>climits</code> header must then be included.
</p>
</li>
<p>
<li>
Given <code>int n1, delta</code> and <code>n1 + delta &lt; n1</code>,
it is possible to rewrite it as <code>n1 &gt; INT_MAX - delta</code>. It must be true
that <code>delta &gt;= 0</code> and the <code>limits.h</code> or <code>climits</code>
header has been included.
</p>
</li>
</ol>
</recommendation>
<example>