    g++ -Wl,-Bstatic -lz -lfoo -Wl,-Bdynamic -lbar -Wl,--as-needed

Will link `zlib` and `libfoo` as static, and `libbar` as dynamic . `--as-needed` will drop any unused dynamic library.

When you only want to statically link one or two libraries with the rest, including system libraries, being dynamic, it is often easier to simply reference the static library by its full name. I.e. rather than use `-l` and `-L` to get g++ to resolve a library from what it finds, simpy add the full path to the library as an input. Taking the g++ command above, to link a `main.o` application main program to static libz and libfoo and dynamic libbar and libglib etc. :

        g++ main.o /usr/lib/libz.a /usr/lib/libfoo.a -lbar


Edit 3 Aug 17: 
I&#39;ve just tripped across [this answer][1] which goes into more detail and offers an alternative way (`-l:`) to specify the library directly.


  [1]: https://stackoverflow.com/questions/6578484/telling-gcc-directly-to-link-a-library-statically

Any idea how one would go about preventing XSS attacks on a node.js app? Any libs out there that handle removing javascript in hrefs, onclick attributes,etc. from POSTed data?

I don&#39;t want to have to write a regex for all that :)

Any suggestions?

Preventing XSS in Node.js / server side javascript

    $.validator.addMethod(&#39;AZ09_&#39;, function (value) { 
    	return /^[a-zA-Z0-9.-_]+$/.test(value); 
    }, &#39;Only letters, numbers, and _-. are allowed&#39;);


When I use somehting like `test-123` it still triggers as if the hyphen is invalid. I tried `\-` and `--`


Including a hyphen in a regex character bracket?

I&#39;ve a program which links to many libraries. `g++`, by default, prefers to link to shared libraries, even if the corresponding archive exists.

How can I change this preference to prefer static archives over dynamic libraries, if a static archive exists?

Note, I used `-static` option, but it tries to find static archive for all libraries which is not what I want.


g++ linker: force static linking if static library exists?

I've a program which links to many libraries. <code>g++</code>, by default, prefers to link to shared libraries, even if the corresponding archive exists.
How can I change this preference to prefer static archives over dynamic libraries, if a static archive exists?
Note, I used <code>-static</code> option, but it tries to find static archive for all libraries which is not what I want.

**This question is about guaranteeing all arguments are of the same type while exhibiting a reject-early behavior with a clean compiler error, not a template-gibberish error**

I&#39;m creating a function (possibly member function, not that it matters... maybe it does?) that needs to accept an unknown number of arguments, but I want all of them to be the same type.  I know I could pass in an array or vector, but I want to be able to accept the list of args directly without extra structure or even extra brackets.  It doesn&#39;t look like variadic functions by themselves are typesafe, and I wasn&#39;t sure how to go about this w/ variadic template functions.  Here&#39;s essentially what I&#39;m aiming for (more than likely not correct code, and totally not for the purpose of getting lists of dragons, lol):


    //typedef for dragon_list_t up here somewhere.

    enum Maiden {
        Eunice
        , Beatrice
        , Una_Brow
        , Helga
        , Aida
    };

    dragon_list_t make_dragon_list(Maiden...) {
        //here be dragons
    }
OR

    template&lt;Maiden... Maidens&gt; dragon_list_t make_dragon_list(Maidens...) {
        //here be dragons
    }

USAGE

    dragon_list_t dragons_to_slay
        = make_dragon_list(Maiden.Eunice, Maiden.Helga, Maiden.Aida)
    ;

Tried a few things similar to the above already, no dice.  Suggestions?  Obvious oversights I may have made?  I know it may not be a huge deal to do this instead:

    dragon_list_t make_dragon_list(std::array&lt;Maiden&gt; maidens) {
        //here be dragons.
    }
    dragon_list_t dragons_to_slay
        = make_dragon_list({Maiden.Eunice, Maiden.Helga, Maiden.Aida})
    ;

but I&#39;d much rather be able to do it the first way if possible.

Specifying one type for all arguments passed to variadic function or variadic template function w/out using array, vector, structs, etc?

I come from a the Objective-C and Cocoa world where there are lots of conventions and many people will say it makes your code beautiful!
Now programming in C++ I cannot find a good document like this one for C++.

http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/CodingGuidelines/CodingGuidelines.html

Standard C++ probably does not have something like above but I hope I can stick to some other SDK or APIs (like Microsoft&#39;s(?),etc) conventions. 

I hope you can provide me with some links.


What is a good naming convention for vars, methods, etc in C++?

Is there a quick way to determine the version of the Boost C++ libraries on a system?

How to determine the Boost version on a system?

In C++ specifically, what are the semantic differences between for example:

    static const int x = 0 ;

and 

    const int x = 0 ;

for both `static` as a linkage and a storage class specifier (i.e. inside and outside a function).




C++ semantics of `static const` vs `const`

I am writing a cross-platform C++ program for Windows and Unix. On the Window side, the code will compile and execute no problem. On the Unix side, it will compile however when I try to run it, I get a segmentation fault. My initial hunch is that there is a problem with pointers.

**What are good methodologies to find and fix segmentation fault errors?**


Fixing Segmentation faults in C++

What I am asking about is the well known &quot;last member of a struct has variable length&quot; trick. It goes something like this:

    struct T {
        int len;
        char s[1];
    };
    
    struct T *p = malloc(sizeof(struct T) + 100);
    p-&gt;len = 100;
    strcpy(p-&gt;s, &quot;hello world&quot;);

Because of the way that the struct is laid out in memory, we are able to overlay the struct over a larger than necessary block and treat the last member as if it were larger than the `1 char` specified.

So the question is: **Is this technique technically undefined behavior?**. I would expect that it is, but was curious what the standard says about this.

PS: I am aware of the C99 approach to this, I would like the answers to stick specifically to the version of the trick as listed above.

Is the &quot;struct hack&quot; technically undefined behavior?

How can I execute a shell script from C in Linux?

How to execute a shell script from C in Linux?

Do I need to treat cases when I actully have nothing to move/copy with `memmove()`/`memcpy()` as edge cases

    int numberOfBytes = ...
    if( numberOfBytes != 0 ) {
        memmove( dest, source, numberOfBytes );
    }

or should I just call the function without checking

    int numberOfBytes = ...
    memmove( dest, source, numberOfBytes );

Is the check in the former snippet necessary?

Can I call memcpy() and memmove() with &quot;number of bytes&quot; set to zero?

How do I get the current time on Linux in milliseconds?

How to get the current time in milliseconds from C in Linux?

I&#39;ve been using the `pthread` library for creating &amp; joining threads in C.

1. When should I create a thread as detached, right from the outset? Does it offer any performance advantage vs. a joinable thread?

2. Is it legal to not do a `pthread_join()` on a joinable (by default) thread? Or should such a thread always use the `detach()` function before `pthread_exit()`ing?

Detached vs. Joinable POSIX threads

I would like to have control over the type of the libraries that get found/linked with my binaries in CMake. The final goal is, to generate binaries _&quot;as static as possible&quot;_ that is to link statically against every library that does have a static version available. This is important as would enable portability of binaries across different systems during testing. 

ATM this seems to be quite difficult to achieve as the FindXXX.cmake packages, or more precisely the find_library command always picks up the dynamic libraries whenever both static and dynamic are available. 

Tips on how to implement this functionality - preferably in an elegant way - would be very welcome!

CMake: how to produce binaries &quot;as static as possible&quot;

What is the difference between a compiler and a linker in C?

What are the differences between a compiler and a linker?

I&#39;m currently writing an app in C++ and found that some of its functionality would be better written in Haskell. I&#39;ve seen instructions on [calling Haskell from C code][1], but is it possible to do the same with C++?

**EDIT:** To clarify, what I&#39;m looking for is a way to compile Haskell code into an external library that g++ can link with the object code from C++.

**UPDATE:** I&#39;ve put up a working example below for anyone else interested (also so I won&#39;t forget).

  [1]: http://www.haskell.org/haskellwiki/Calling_Haskell_from_C

Calling Haskell from C++ code

I wanted to know in depth meaning and working of compiler, linker and loader.
With reference to any language preferably c++.


What is compiler, linker, loader?

Linux binaries are usually dynamically linked to the core system library (libc). This keeps the memory footprint of the binary quite small but binaries which are dependent on the latest libraries will not run on older systems. Conversely, binaries linked to older libraries will run happily on the latest systems.

Therefore, in order to ensure our application has good coverage during distribution we need to figure out the oldest libc we can support and link our binary against that. 

How should we determine the oldest version of libc we can link to?

Linking against an old version of libc to provide greater application coverage

I tried this : 

    #ifndef __TEST__
    #define __TEST__
 
    namespace std
    {
        template&lt;typename T&gt;
        class list;
    }
 
    template&lt;typename T&gt;
    void Pop(std::list&lt;T&gt; * l)
    {
        while(!l-&gt;empty())
            l-&gt;pop();
    }
 
    #endif

and used that function in my main. I get errors. Of course, I know that there are more template params for `std::list` (allocator I think). But, that is beside the point. Do I have to know the full template declaration of a template class to be able to forward declare it?

EDIT: I wasn&#39;t using a pointer before - it was a reference. I&#39;ll try it out with the pointer.

How to forward declare a template class in namespace std?

How can I view symbols in a .o file? nm does not work for me. I use g++/linux.

How to view symbols in object files?

I&#39;m trying to set up a Windows PowerShell alias to run MinGW&#39;s g++ executable with certain parameters. However, these parameters need to come after the file name and other arguments. I don&#39;t want to go through the hassle of trying to set up a function and all of that. Is there a way to simply say something like:

    alias mybuild=&quot;g++ {args} -lib1 -lib2 ...&quot;

or something along those lines? I am not all that familiar with PowerShell, and I&#39;m having a difficult time finding a solution. Anyone?



How can I write a PowerShell alias with arguments in the middle?

I&#39;m building a simple C++ program and I want to temporarily substitute a system supplied shared library with a more recent version of it, for development and testing.

I tried setting the LD_LIBRARY_PATH variable but the linker (ld) failed with:

&gt; /usr/bin/ld: cannot find -lyaml-cpp

I expected that to work because according to the ld man page:

&gt; The linker uses the following search
&gt; paths to locate required shared
&gt; libraries:  ... For a native linker, 
&gt; the contents of the environment variable
&gt; &quot;LD_LIBRARY_PATH&quot;...

I then tried setting the LIBRARY_PATH, and that worked.

According to the GCC manual:

&gt; The value of
&gt; LIBRARY_PATH is a colon-separated list
&gt; of directories, much like PATH. When
&gt; configured as a native compiler, GCC
&gt; tries the directories thus specified
&gt; when searching for special linker
&gt; files, if it can&#39;t find them using
&gt; GCC_EXEC_PREFIX. Linking using GCC
&gt; also uses these directories when
&gt; searching for ordinary libraries for
&gt; the -l option (but directories
&gt; specified with -L come first).

As the (GCC) manual suggests, LIBRARY_PATH works because I link with GCC.


But..

 - Since I link with gcc why ld is
   being called, as the error message
   suggests? 
 - What&#39;s the point of
   having two variables serving the same
   purpose? Are there any other
   differences?

LD_LIBRARY_PATH vs LIBRARY_PATH

Also, can anyone point me to a good tutorial on the subject? I can&#39;t find any.

How to use profile guided optimizations in g++?

I have a static library, say `mystaticlib.a`. I want to see its contents, such as the number of object files inside it. 

How can I do this on gcc?

Contents of a static library

I have 2 static Linux libraries, created by `ar cr`, `libabc.a` and `libxyz.a`.&lt;br&gt;
I want to merge them into one static library `libaz.a`.&lt;br&gt;
How can I do this.

I want to create a merged static library,  not to give both libraries to final link of applications.

How to merge two &quot;ar&quot; static libraries into one?

How can I statically link only a some specific libraries to my binary when linking with GCC?

`gcc ... -static ...` tries to statically link **all** the linked libraries, but I haven&#39;t got the static version of some of them (eg: libX11).

static linking only some libraries

&gt; ## Alternate titles to aid search
&gt; - Xcode can&#39;t find header 
&gt; - Missing .h in Xcode
&gt; - Xcode .h file not found
&gt; - lexical or preprocessor issue file not found

I&#39;m working on an iOS application project which came from Xcode 3.  I have now moved to Xcode 4 my project builds a number of static libraries.

Those static libraries also declare public headers and those headers are used by the application code. In Xcode 3.x the headers were copied (as a build phase) to the `public headers directory`, then in the application project the `public headers directory` was added to the `headers search list`.

Under Xcode 4 the build directory is moved to `~/Library/Developer/Xcode/DerivedData/my-project`. 

The problem is how do I reference this new location in the headers search settings? It seems that:

- `public headers directory` is relative to `DerivedData` directory, but
- `headers search` directory is relative to something else (possibly the project location)

How should I set up a static library target for iOS development in Xcode 4 that will ensure the header files are made available to the clients that use the static library when trying to compile as a dependancy?

Xcode 4 can&#39;t locate public header files from static library dependency

I am quite new to xcode and objective-c. I want to ask a very basic question.

I saw that when &quot;linking binary to libraries&quot; in project settings, there are differences about framework and libraries, imported from other projects in workspace.

First question, why is there a framework? And why is there a library? Cannot my library be a framework?

And then, from a *.h* file, how can I call classes from my imported static library?

I suppose there must be a prefix, but I couldn&#39;t find it.
Neither &lt;ProjName/Myclass.h&gt; nor &quot;ProjName/Myclass.h&quot; are working.

Please, be as specific as you can.

Thanks

Content Type	Original Author	Original Content on Stackoverflow
Question	kumar	View Question on Stackoverflow
Solution 1 - C++	naideflan	View Answer on Stackoverflow
Solution 2 - C++	stanthomas	View Answer on Stackoverflow

g++ linker: force static linking if static library exists?

C++ Problem Overview

C++ Solutions

Solution 1 - C++

Solution 2 - C++

Including a hyphen in a regex character bracket?

Preventing XSS in Node.js / server side javascript

Attributions