[SOLVED] How to use libraries ".lib" and ".a" files in GCC

Issue

I have simple C code that uses some functions of libavcodec in FFmpeg. I try to compile the code with GCC (on Windows using MinGW) as follows:

gcc -o mycode mycode.c

But I get a lot of errors like "undefined reference to av_free". I know that these functions are defined in the libraries of FFmpeg. I do access files like avcodec.lib and libavcodec.dll.a, but I don't know how to use them with GCC so that I can compile and make my file. How can I solve this problem?

Solution

Try something like:

gcc -o mycode mycode.c -L C:\path\to\avcodec -lavcodec

I don't have Windows, so I cannot test it myself.

The point is that you need to tell gcc that some functions are in avcodec.lib / .dll. After the -L you tell where the .a / .dll is, then you must tell the linker to actually consider the avcodec.lib / .dll, that corresponds to -lavcodec.

Answered By - Ali

Answer Checked By - Katrina (WPSolving Volunteer)