Nested static libraries in Visual Studio? - c

I have a static library for a Vector implementation in C.
I am now making a new library that is going to rely on the Vector in order to function property. This new library is called String. Both are static libraries created in Visual Studio with their own .c and .h files.
I do the following just like I would when referencing any other static library
Create new static library. Create .c and .h files in it.
project -> properties -> C/C++ -> Additional include directories and set as the folder that contains the .c and .h files for my Vector
File -> Add -> Existing Project and set the .vcxproj file of the Vector project.
In my solution explorer, I went under my String solution and right clicked References and then check-marked the Vector box that shows up.
At this point, my String is now correctly able to see Vector.
The problem
When I open a new project, repeat those same steps except with String as the target library, I get the following error:
Severity Code Description Project File Line Suppression State
Error MSB8006 The Platform for project 'C-DataStructuresLib.vcxproj' is invalid. Platform='HPD'. This error may also appear if some other project is trying to follow a project-to-project reference to this project, this project has been unloaded or is not included in the solution, and the referencing project does not build using the same or an equivalent Platform. CStringLib C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V140\Microsoft.Cpp.InvalidPlatform.Targets 21
The line:
This error may also appear if some other project is trying to follow a project-to-project reference to this project, this project has been unloaded or is not included in the solution, and the referencing project does not build using the same or an equivalent Platform
Is correct because that's exactly what I'm trying to do. How can this be fixed?

Are you trying to compile as 64-bit project?
Check in the property page the section: Linker -> Advanced -> Target Machine

Related

Ufft example compilation

I want to run the example project which is available for free from this link. It is a simple FFT library and needs no compiler. In it, there is an example c file with its required header files and .c files.
When I try to run it in Vivado SDK I get errors of multiple definitions of fft and ifft. How can I run this example inside SDK?
What I had done is created an empty application project and then imported all these files inside src folder and then selected build the project option but didn't succeed in building and running the project.
I guess, looking at the ufft.zip archive, that you've tried to link files issued form the compilation of fft-dit.c and fft-dif.c.
Both files define ftt functions using differents method (see README).
You have to choose betwen using ftt-dif.c or ftt-dit.c, not both.
This is the same for itt-dif.c and itt-dit.c, choose one, not both.

Borland C++ Builder 4 [Linker Error] Unresolved external

I'm trying to compile an old project in Borland C++ Builder 4. I have a working exe and the source files for that, therefore someone must have managed to compile it earlier. However, when I open the project, check if the project hs all the necessary files in the resources and try to compile it, I keep getting the following linker error:
[Linker Error] Unresolved external '_fastcall TMapperForm::Button1Click(System::TObject*)' referenced from ...\Unit1.obj
I can see that it cannot find an object in the library but I am not sure how to resolve it, because the obj file with the same name as the main cpp file is in the same file as the other files of the project and seems fine.
I have looked through the answers provided here for similar linker errors but none of what these have suggested worked for me. I have already tried the following:
Adding the .obj file to the Project Resources.
Trying to add pragma lines manually such as #pragma link (Unit1.obj)
Making sure that in Project>Options>Directories the right Include and Library paths were selected.
Checking if all the packages have been added.
None of this seems to work. I am fairly new to C++ and C++ Builder, so I am hoping that it is something trivial.
Has anybody seen this particular error?
The error was caused by a missing handler or more precisely a handler containing nothing.
While the handler for the button contained nothing, the TMapperForm class still included the definitions for an extra button named Button1 but it was not used. Commenting out the method and the declaration in the TMapperForm class (in the header file for Unit1) along with the handler in the C++ file resolved the problem.

Using external static library in LPCXpresso

I am using the LPCXpresso IDE to program my microcontroller to use the libjpeg library for a particular application. However, I cannot seem to get the LPCXpresso IDE to recognize libjpeg. The way I see it, there are two options:
1) Take the jpeglib.a file, include it as an external library, and then attempt to import jpeglib.h. I have tried this, at the IDE still does not recognize jpeglib.h.
2) Create a new static library from the libjpeg source code. Is this my only option? It seems a bit excessive.
Any tips regarding adding/linking external libraries in LPCXpresso would be greatly appreciated. Thanks!
You can easily add a library to Eclipse/LPCXpresso by creating a new project (not a C project or a LPCXpresso project but a 'normal' project) by clicking File->New->Project. Name is as you wish, let's say 'JPEG'. Add your library file to it under the folder 'lib' (you have to create the folder first). Call the library file 'libJPEG.a'. Also include the header file under the folder 'inc'. It is not mandatory to create these folders by the way, but it makes it all more organised.
The edit the properties of the project that's needs to include the header and library. Right click the project and choose properties. Go to C/C++ Build->Settings->MCU C compiler->Includes and add the include path of the inc folder of the library project. The go to C/C++ Build->Settings->MCU Linker->Libraries and add the library file WITHOUT the lib in front of the file name, hence just JPEG. Also add the library search path below (point to the lib folder).
That's all!

eclipse include custom files (c)

Not sure how to phrase the question.
I've created a few files for my c project that I would like to use for multiple projects.
Project root: ~/workspace/myproject
Files :
~/workspace/myproject/customlib/myfile.h
~/workspace/myproject/customlib/myfile.c
I was able to move them from my eclipse (Code Composer Studio) workspace and replace them with symlinks to their new location.
Custom lib dir: ~/myfiles/customlib
This is working fine but I'd rather not use the symlinks as it becomes necessary to add those symlinks to any project where I want my customlib files. Also when copy/pasting a project in eclipse it doesn't seem to understand the symlink and creates a copy of the file rather than the symlink.
I've set up an include path to ~/myfiles/ but when I compile I get a bunch of unresolved symbol errors.
My custom files depend on files from other include paths as well. (if that might be a hint as to why things are breaking)
Is there another way I can link in these files?
I figured out how I can do what I'm looking for but can't actually post the answer for 8 hours so I'll answer it here.
I was able to add the .c files as "Linked Resources" to my project.
So in the end I had an include path to ~/myfiles and a linked resource ~/myfiles/customlib/myfile.c.
Linked Resources can be found under Project Properties -> Resource -> Linked Resources -> Linked Resources(tab)
Unfortunately, my environment, Code Composer Studio 6 on Ubuntu would not allow me to actually add a linked resource through the IDE.
As a workaround I added the linked resource directly to the .project file.
~/workspace/myproject/.project
Under the section labeled "natures" I added
<linkedResources>
<link>
<name>myfile.c</name>
<type>1</type>
<locationURI>$%7BPARENT-2-PROJECT_LOC%7D/myfiles/customlib/myfile.c</locationURI>
</link>
</linkedResources>
The "$%7BPARENT-2-PROJECT_LOC%7D" refers to ~/workspace/myproject/../../ (a.k.a. ~/). The 2 tells it how many ../'s
In case you don't get the locationURI right the first time you should be able to edit the file path from Project Properties -> Resource -> Linked Resources -> Linked Resources(tab)
You can use any defined build variables for the locationURI. Here is another way to write the location URI. PROJECT_LOC/../../myfiles/customlib/myfile.c
Since this is an eclipse project file it will be overwritten with whatever eclipse decides is the proper format for locationURI
You can place the linked resource into a folder in your project by modifying the tag. projectsubfolder/myfile.c. This will create a folder projectsubfolder under your project directory. ~/workspace/myproject/projectsubfolder
Unfortunately this isn't an optimal solution as I will need to add linkedresource entries for every source file I create in my custom lib. CCS fumbles the linked resources when doing a project copy/paste, requiring you to add the linked resources again to your copied project.
In the end it feels like a solution but it really doesn't have much benefit over symlinked files. The only one being that when I copy/paste a project I will know the project isn't using the correct files when it doesn't compile. (symlinking will make a working project with copies of the files instead of the originals)
I imagine I will need to learn about creating .lib files to make the inclusion a little more pain free.

Preserving Header Directory Structure in Xcode for Static Library

I'm developing a static library in C++ using Xcode. I have an Installation Directory set where it copies all of my public header files, but when I compile it just copies all the headers into one directory. Is there a way to tell Xcode to preserve the directory structure of my header files? Thanks in advance!
I also needed to preserve the header file directory structure for a C++ library project and I finally managed to do it. It is ridiculously complicated with XCode, compared to the simple nature of the task. The key is to create "folder references" at first, then to copy the header folders in an extra build phase and afterwards to delete .c/.cpp-files from these exported header folders with a script, because XCode will not only copy the .h-files.
I've written a blog post here on how to all achieve that, because it's more tricky in detail. You might also want to check out an example XCode project that I've pot on github.
When you add files to your project, you have to choose next parameter on an additional window "Create folder references for any added folders". And then all your files will have fixed path for your files and will save structure after compilation.

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