Thread: Undefined reference to a function, linker error

This is a rookie question and I might be doing something stupid, but I wrote a C program that includes two non default libraries: curl and libxml2. I am trying to go through the compilation process in detail to learn the process and statically link the libraries. These are the steps I took:
Downloaded libxml2 and curl and compiled it with the included makefile and did the following:

Code:

ar rcs libcurl.a  /home/${USER}/Desktop/Curl/curl-7.73.0/lib/*.o 
ar rcs libxml2.a /home/${USER}/Desktop/xml2/libxml2-2.7.2/*.o

Even though I only use a few functions from those libraries I packed all together in case they needed each other, or at least I think that's how it works. I copied the generated arhive library to a separate location and lastly I did:

Code:

cp ~/Desktop/libxml2-2.7.2/libxml2.a ~/Desktop/libs/    
cp ~/Desktop/Curl/curl-7.73.0/lib/libxml2.a ~/Desktop/libs/
gcc WolframParser.c -I/home/${USER}/Desktop/Curl/curl-7.73.0/include/ -I/home/${USER}/Desktop/libxml2-2.7.2/include/ -L/home/${USER}/Desktop/libs/ -lcurl -lxml2 -lm

The linker reports a bunch of errors of undefined references, the likes of:

Code:

        /usr/bin/ld: /home/${USER}/Desktop/libs//libcurl.a(libcurl_la-multi.o): in function `multi_getsock':
    multi.c:(.text+0x18e): undefined reference to `Curl_ssl_getsock'
    /usr/bin/ld: /home/${USER}/Desktop/libs//libcurl.a(libcurl_la-easy.o): in function `curl_global_init':
    easy.c:(.text+0x172): undefined reference to `Curl_ssl_init'
    /usr/bin/ld: /home/${USER}/Desktop/libs//libcurl.a(libcurl_la-easy.o): in function `curl_global_init_mem':
    easy.c:(.text+0x22e): undefined reference to `Curl_ssl_init'
    /usr/bin/ld: /home/${USER}/Desktop/libs//libcurl.a(libcurl_la-easy.o): in function `curl_global_cleanup':
    easy.c:(.text+0x295): undefined reference to `Curl_ssl_cleanup'
    . . .

Can someone please point out what I did wrong, and can this be done like this at all?

Thanks for the reply!

I could have installed curl with a package manager (in fact I did that a while ago, I didn't manually mess with object and archive files, I just called gcc on the source file, and it worked then) but I wanted to understand why my current understanding how linker works is wrong.