You must `#define NDEBUG` (or use the flag `-DNDEBUG` with _g++_) this will disable assert as long as it&#39;s defined before the inclusion of the assert header file.

Use `#define NDEBUG`


&gt;**7.2  Diagnostics &lt;assert.h&gt;**

&gt;1      The header &lt;assert.h&gt;deﬁnes the **assert** macro and refers to another macro,

&gt;  **NDEBUG**
 
&gt;which  is not deﬁned  by `&lt;assert.h&gt;`. 
If **NDEBUG** is  deﬁned  as  a  macro  name  at  the point in the source ﬁle where &lt;assert.h&gt; is included, the **assert** macro is deﬁned
simply as

&gt;`#define assert(ignore) ((void)0)`

&gt;The **assert** macro is redeﬁned according to the current state of **NDEBUG** each time that
`&lt;assert.h&gt;` is included.

The `-g` flag doesn&#39;t affect the operation of `assert`, it just ensures that various debugging symbols are available.

Setting `NDEBUG` is the standard (as in official, ISO standard) way of disabling assertions.


You can either disable assertions completely by 

    #define NDEBUG
    #include &lt;assert.h&gt;

or you can set NDEBUG (via -DNDEBUG) in your makefile/build procedure depending on whether you want a productive or dev version.

Yes, define `NDEBUG` on the command line/build system with the preprocessor/compiler option `-DNDEBUG`.

This has nothing to do with the debugging info inserted by `-g`.

How to clear the `ConcurrentBag`? it don&#39;t have any method like `Clear` or `RemoveAll`...

How to remove all Items from ConcurrentBag?

I notice that in my copy of the SGI STL reference, there is a page about Character Traits but I can&#39;t see how these are used? Do they replace the string.h functions? They don&#39;t seem to be used by `std::string`, e.g. the `length()` method on `std::string` doesn&#39;t make use of the Character Traits `length()` method. Why do Character Traits exist and are they ever used in practice?

What is the point of STL Character Traits?

My code is full of calls to &lt;code&gt;assert(condition)&lt;/code&gt;.
In the debug version I use &lt;code&gt;g++ -g&lt;/code&gt; which triggers my assertions.
Unexpectedly, the same assertions are also triggered in my release version, the one compiled without &lt;code&gt;-g&lt;/code&gt; option.

How can I completely disable my assertions at compile time? Should I explicitly define &lt;code&gt;NDEBUG&lt;/code&gt; in any build I produce regardless of whether they are debug, release or anything else?

How can I completely disable calls to assert()?

<p>My code is full of calls to <code>assert(condition)</code>.
In the debug version I use <code>g++ -g</code> which triggers my assertions.
Unexpectedly, the same assertions are also triggered in my release version, the one compiled without <code>-g</code> option.</p>
<p>How can I completely disable my assertions at compile time? Should I explicitly define <code>NDEBUG</code> in any build I produce regardless of whether they are debug, release or anything else?</p>


If I override `operator=` will the copy constructor automatically use the new operator? Similarly, if I define a copy constructor, will `operator=` automatically &#39;inherit&#39; the behavior from the copy constructor?

The copy constructor and assignment operator

The following snippet produces an &quot;ambigious call to foo&quot; error during compilation, and I&#39;d like to know if there is any way around this problem without fully qualifying the call to foo:

    #include &lt;iostream&gt;
    
    struct Base1{
    	void foo(int){
    	}
    };
    
    struct Base2{
    	void foo(float){
    	}
    };
    
    struct Derived : public Base1, public Base2{
    };
    
    int main(){
    	Derived d;
    	d.foo(5);
    
    	std::cin.get();
    	return 0;
    }
So, question is as the title says. Ideas? I mean, the following works flawlessly:

    #include &lt;iostream&gt;

    struct Base{
    	void foo(int){
    	}
    };

    struct Derived : public Base{
    	void foo(float){
    	}
    };
    
    int main(){
    	Derived d;
    	d.foo(5);
    
    	std::cin.get();
    	return 0;
    }

Why do multiple-inherited functions with same name but different signatures not get treated as overloaded functions?

How portable is this conversion. Can I be sure that both assertions pass?

    int x = 4&lt;5;
    assert(x==1);
    
    x = 4&gt;5;
    assert(x==0);

Don&#39;t ask why. I know that it is ugly. Thank you.

bool to int conversion

Is it possible to implement `static` class member functions in *.cpp file instead of doing
it in the header file ?

Are all `static` functions always `inline `?

How to implement static class member functions in *.cpp file?

I&#39;m trying to generate calling graph with which to find out all the possible execution paths that are hitting a particular function (so that I don&#39;t have to figure out all the paths manually, as there are many paths that lead to this function). For instance:

    path 1: A -&gt; B -&gt; C -&gt; D  
    path 2: A -&gt; B -&gt; X -&gt; Y -&gt; D  
    path 3: A -&gt; G -&gt; M -&gt; N -&gt; O -&gt; P -&gt; S -&gt; D  
    ...  
    path n: ...

I have tried Codeviz and Doxygen, somehow both results show nothing but callees of target function, D. In my case, D is a member function of a class whose object will be wrapped within a smart pointer. Clients will always obtain the smart pointer object through a factory in order to invoke D.

Does anyone know how to achieve this?

How to Generate a calling graph for C++ code

I print out the output of C preprocessor by using

    gcc -E a.c
The output contains many lines like

    # 1 &quot;a.c&quot;
    # 1 &quot;&lt;built-in&gt;&quot;
    # 1 &quot;&lt;command-line&gt;&quot;
    # 1 &quot;a.c&quot;
    # 1 &quot;c:\\mingw\\bin\\../lib/gcc/mingw32/4.5.0/../../../../include/stdio.h&quot; 1 3
    # 19 &quot;c:\\mingw\\bin\\../lib/gcc/mingw32/4.5.0/../../../../include/stdio.h&quot; 3
    # 1 &quot;c:\\mingw\\bin\\../lib/gcc/mingw32/4.5.0/../../../../include/_mingw.h&quot; 1 3
    # 31 &quot;c:\\mingw\\bin\\../lib/gcc/mingw32/4.5.0/../../../../include/_mingw.h&quot; 3
           
    # 32 &quot;c:\\mingw\\bin\\../lib/gcc/mingw32/4.5.0/../../../../include/_mingw.h&quot; 3
    # 20 &quot;c:\\mingw\\bin\\../lib/gcc/mingw32/4.5.0/../../../../include/stdio.h&quot; 2 3

I&#39;ve never seen this kind of syntax in C. Can someone explain what this is doing?

What is the meaning of lines starting with a hash sign and number like &#39;# 1 &quot;a.c&quot;&#39; in the gcc preprocessor output?

I recently encountered some code that gcc would not compile without this arg. I checked the gcc man page, but did not find this specific option. I did find `XOPEN_SOURCE`, but there was little explanation of what it does.

Can someone please elaborate? I know `-D_XOPEN_SOURCE` can be set to different values, such `400`, `600`, but what do those do?

What does -D_XOPEN_SOURCE do/mean?

I am trying to understand how can I make my program a daemon.So some things which I came across are In general, a program performs the following steps to become a daemon:  

1. Call `fork( )`. 
2. In the parent, call `exit( )`. This ensures that the original parent (the daemon&#39;s
grandparent) is satisfied that its child terminated, that the daemon&#39;s parent is no
longer running, and that the daemon is not a process group leader. This last point
is a requirement for the successful completion of the next step.  

3. Call `setsid( )`, giving the daemon a new process group and session, both of
  which have it as leader. This also ensures that the process has no associated
  controlling terminal (as the process just created a new session, and will not assign
  one).

4. Change the working directory to the root directory via `chdir( )`. This is done
because the inherited working directory can be anywhere on the filesystem.
Daemons tend to run for the duration of the system&#39;s uptime, and you don&#39;t want
to keep some random directory open, and thus prevent an administrator from
unmounting the filesystem containing that directory.

5. Close all file descriptors. 
6. Open file descriptors 0, 1, and 2 (standard in, standard out, and standard error)
and redirect them to `/dev/null`.


&lt;pre&gt;&lt;code&gt;#include &amp;lt;sys/types.h&amp;gt;
#include &amp;lt;sys/stat.h&amp;gt;
#include &amp;lt;stdlib.h&amp;gt;
#include &amp;lt;stdio.h&amp;gt;
#include &amp;lt;fcntl.h&amp;gt;
#include &amp;lt;unistd.h&amp;gt;
#include &amp;lt;linux/fs.h&amp;gt;

int main (void)
{
    pid_t pid;
    int i;
    
    /* create new process */
    pid = fork ( );  
    if (pid == -1)  
        return -1;  
    else if (pid != 0)  
        exit (EXIT_SUCCESS);  

    /* create new session and process group */  
    if (setsid ( ) == -1)  
        return -1;  

    /* set the working directory to the root directory */  
    if (chdir (&quot;/&quot;) == -1)  
        return -1;  

    /* close all open files--NR_OPEN is overkill, but works */  
    for (i = 0; i &amp;lt; NR_OPEN; i++)  
        close (i);  

    /* redirect fd&#39;s 0,1,2 to /dev/null */  
    open (&quot;/dev/null&quot;, O_RDWR);  
    /* stdin */  
    dup (0);  
    /* stdout */  
    dup (0);  
    /* stderror */  
    
    /* do its daemon thing... */  
    
    return 0;  
}&lt;/code&gt;&lt;/pre&gt;  



Can some one give me a link to existing source code of some program like Apache so that I can understand this process in more depth.


how to make a process daemon

I&#39;m a little bit confused about something. I was under the impression that the correct way of reading a C string with `scanf()` went along the lines of

(never mind the possible buffer overflow, it&#39;s just a simple example)

    char string[256];
    scanf( &quot;%s&quot; , string );

However, the following seems to work too,

    scanf( &quot;%s&quot; , &amp;string );

Is this just my compiler (gcc), pure luck, or something else?

Why does reading into a string buffer with scanf work both with and without the ampersand (&amp;)?

Does anyone know whether there is an `assert` or something like that which can test whether an exception was thrown in the code being tested?

PHPUnit assert that an exception was thrown?

I saw somewhere assert used with a message in the following way:

    assert((&quot;message&quot;, condition));

This seems to work great, except that gcc throws the following warning:

    warning: left-hand operand of comma expression has no effect

How can I stop the warning?

assert() with message

I want to use `assert obj != null : &quot;object cannot be null&quot;` on Android device. The assert doesn&#39;t seem to work, so I searched online and I found this local solution: 

&gt; adb shell setprop debug.assert 1

it does work on my local machine.

I want to run this command using my Eclipse project(so it would be in the source control).
How can I do it?



How to use assert in android?

I&#39;ve read two really interesting pieces of advice, recently:

 1. In the comments to [this StackOverflow answer][1], @Mike Weller says to leave your asserts on in production code... what&#39;s the performance hit, really? Is there any reason NOT to leave them in? 
 2. In [Vincent Gable&#39;s blog][2], he states that you should prefer `assert` over `NSAssert`... is there any reason NOT to use `assert`? (it&#39;s less letters :))


  [1]: https://stackoverflow.com/questions/1375786/whats-the-point-of-nsassert-actually/1375819#1375819
  [2]: http://vgable.com/blog/2008/12/04/nsassert-considered-harmful/

NSAssert vs. assert: Which do you use, and when?

I googled to find the assert methods list. But it seems like this documentation is very well hidden. Does anyone know where it is?

Content Type	Original Author	Original Content on Stackoverflow
Question	Abruzzo Forte e Gentile	View Question on Stackoverflow
Solution 1 - C++	GWW	View Answer on Stackoverflow
Solution 2 - C++	Prasoon Saurav	View Answer on Stackoverflow
Solution 3 - C++	Alnitak	View Answer on Stackoverflow
Solution 4 - C++	dcn	View Answer on Stackoverflow
Solution 5 - C++	Fred Foo	View Answer on Stackoverflow

How can I completely disable calls to assert()?

C++ Problem Overview

C++ Solutions

Solution 1 - C++

Solution 2 - C++

Solution 3 - C++

Solution 4 - C++

Solution 5 - C++

What is the point of STL Character Traits?

How to remove all Items from ConcurrentBag?

Attributions