Looking for good explanation of creation process of Static Lib and it's Test App

[sitesv]

@SGaist said in Looking for good explanation of creation process of Static Lib and it's Test App:

First thing: are you sure your library is properly statically built on Windows ?

How I should check this?

[SGaist]

Are you properly setting the static flag in your library project ? Do you get a .dll when building on Windows ?

[sitesv]

@SGaist said in Looking for good explanation of creation process of Static Lib and it's Test App:

Are you properly setting the static flag in your library project ? Do you get a .dll when building on Windows ?

Yes. Dll and Lib files are created after building lib.

[SGaist]

Then your library is not build statically and you are not properly exporting symbols.

For that second part see here.

[sitesv]

@SGaist thanks. I will recode my lib.

I there any way to debug dynamic/static lib?

[SGaist]

Sure, use a debug build of your library.

[sitesv]

@SGaist ones more Q:
But how the same project works in Linux?

[SGaist]

Because the symbol exportation does not work the same on Linux.

[gde23]

When you have a library under windows you need to explicitly export the symbols.
On linux it is not necessary because the symbols are managed in another way.

Typically this is done using a preprocessor define that you add at any function / class that you wanna export like (just look it up on stackoverflow)

#ifdef WIN32
    #define DECL_EXPORT __declspec(dllexport)
    #define DECL_IMPORT __declspec(dllimport)
#else
    #define DECL_EXPORT
    #define DECL_IMPORT
#endif

[SGaist]

@gde23 said in Looking for good explanation of creation process of Static Lib and it's Test App:

When you have a library under windows you need to explicitly export the symbols.
On linux it is not necessary because the symbols are managed in another way.

Typically this is done using a preprocessor define that you add at any function / class that you wanna export like (just look it up on stackoverflow)

#ifdef WIN32
    #define DECL_EXPORT __declspec(dllexport)
    #define DECL_IMPORT __declspec(dllimport)
#else
    #define DECL_EXPORT
    #define DECL_IMPORT
#endif

That is incomplete, The macro to use depend whether you are building the library or using it. See the dedicated chapter in Qt's documentation for a clean way to handle that.

[sitesv]

@SGaist I checked my code... It is matches to link.
But lib and dll files are created.

Should this code be in pro file:

CONFIG += staticlib

?

So, I have included this string to pro and as a result a lib file only.

Could you please see my test apps? ==> app

[gde23]

@SGaist You are right. I forgot to mention that part.
@sitesv The dll will be created also if you do not export the symbols. But the exe will not know about the function/class inside the dll so it will not find them.
Did you include the defines as in the description SGaist posted?

[sitesv]

@gde23 said in Looking for good explanation of creation process of Static Lib and it's Test App:

@SGaist You are right. I forgot to mention that part.
@sitesv The dll will be created also if you do not export the symbols. But the exe will not know about the function/class inside the dll so it will not find them.
Did you include the defines as in the description SGaist posted?

Yes. I checked it. Could you view my code by this link?

UPD: I inserted the line "extern int test();" to main.cpp. And voila!