Databases
StackOverflow2013
Postsdbo
POCompile time optimization - removing debug prints from release binaries
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POCompile time optimization - removing debug prints from release binaries
    primarykey
    data
    text
    <p>It is my very first post, so I would like to welcome with everybody. The problem I have occurred is the code optimization at compilation time, and to be more specific removing debug prints.</p> <p>Let's imagine that we have native <code>syslog logger</code> and we are wrapping it (without using of macros, it is very important note!) with following code:</p> <pre><code>enum severity { info_log, debug_log, warning_log, error_log }; template &lt;severity S&gt; struct flusher { logger* log_; flusher(logger* log) : log_(log) {} flusher(flusher&amp; rhs) : log_(rhs.log_) {} ~flusher() { syslog(S, log_-&gt;stream.str()); log_-&gt;stream.str(""); } operator std::ostream&amp; () { return log_-&gt;stream; } }; #ifdef NDEBUG template &lt;&gt; struct flusher&lt;debug_log&gt; { flusher(logger*) {} flusher(flusher&amp;) {} ~flusher() {} template &lt;typename T&gt; flusher&amp; operator&lt;&lt;(T const&amp;) { return *this; } }; #endif struct logger { std::ostringstream stream; template &lt;severity T&gt; flusher&lt;T&gt; operator&lt;&lt;(flusher&lt;T&gt; (*m)(logger&amp;)) { return m(*this); } }; inline flusher&lt;info_log&gt; info(logger&amp; log) { return flusher&lt;info_log&gt;(&amp;log); } inline flusher&lt;debug_log&gt; debug(logger&amp; log) { return flusher&lt;debug_log&gt;(&amp;log); } inline flusher&lt;warning_log&gt; warning(logger&amp; log) { return flusher&lt;warning_log&gt;(&amp;log); } inline flusher&lt;error_log&gt; error(logger&amp; log) { return flusher&lt;error_log&gt;(&amp;log); } </code></pre> <p>I thought that the empty implementation of flusher will encourage compiler to remove such useless code, but with both <code>O2</code> and <code>O3</code> it is not removed. </p> <p>Is there any possibility to provoke mentioned behaviour?</p> <p>Thanks in advance </p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USVikalp Patel
    1. USfttrobin
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POCompile time optimization - removing debug prints from release binaries
      1. This table or related slice is empty.
      1. VTApproveEditSuggestion
    2. VO
      singulars
      1. POCompile time optimization - removing debug prints from release binaries
      1. USquaylar
      1. VTFavorite
    1. COWhat code are you still seeing?
      singulars
      1. POCompile time optimization - removing debug prints from release binaries
      1. USimreal
    2. COI have made simple test with NDEBUG flag: inline int f() { std::cout << 1; return 1; } logger log; log << debug << f(); I would like to create behaviour which 1 will not be printed at stdout, but it is
      singulars
      1. POCompile time optimization - removing debug prints from release binaries
      1. USfttrobin
    3. COYes, your code would not avoid the call to f(), or any side effects it might have. If you wanted to do that, you must pass in an unevaluated function i.e. std::function, function pointer, etc, or use a macro.
      singulars
      1. POCompile time optimization - removing debug prints from release binaries
      1. USjmetcalfe
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload