How to Include .lib

1

I have a library where function declarations are given in .h file and function definitions inside .lib file. When I try and build the project it obviously fails, stating that it cannot find specific functions definitions.

I have tried using several options with lib_extra_dirs. I have this library inside src file with other relevant header files but just in case I added it into lib project folder:

lib_extra_dirs =
    src/BSEC/Inc/libalgobsec.lib
    src/BSEC/Inc
    lib/libalgobsec.lib
    libalgobsec.lib
    libalgobsec

I have also tried this with build flags:

build_flags = 
    -Lsrc/BSEC/Inc/libalgobsec.lib
    -Lsrc/BSEC/Inc/libalgobsec
    -Lsrc/BSEC/Inc
    -Llib/libalgobsec
    -Llibalgobsec

None of shown approaches work because I keep getting linker errors of undefined functions that come with this library inside .lib file. Which method does what I want to achieve?

2

.lib? Was that compiled with Visual Studio / MSVC, for desktop instead of a microcontroller?

And, as the docs say, to link against a static library, all you have to do is a add the folder where the library resides to the library search path (-L) and then instruct to link against the library (-l without lib prefix or suffix).

build_flags =
   -Lsrc/BSEC/Inc/
   -lalgobsec
3

Yes, I have header files with function declarations and .lib file. I don’t exactly get your question. I’m trying to compile in VS Code using GCC on Windows. End target is microcontroller.

4

Gcc produces .a as its static library format (archive). .lib is indicitive of the MSVC compiler.

But try out the above and see what happens

5

The thing is that I got .lib file from external source which provided this library. There is no source code. There are only header files and static library.

This is what I get from trying to build what you suggested. Not sure why it says that it cannot find this library even though I pointed it exactly where library file is located at.

2023-05-20 23_30_02-platformio.ini - Untitled (Workspace) - Visual Studio Code
2023-05-20 23_30_02-platformio.ini - Untitled (Workspace) - Visual Studio Code2612×765 119 KB

6

Yeah it likely doesn’t find it because GCC can’t process .lib files. It wants .a files.

All of the precompiled files in here are .a too

Are you 100% sure that .lib file is the result that came out of the ARM GCC cross compiler with -mcpu set to Cortex-M7, as your STM32F7 needs it?

7

Thank you for pointing this out. It was my fault for copying false library files into my PlatformIO project. You’re right, under GCC folder in BSEC library there are .a files which I need.