What versions of libraries are in GNU ARM Toolchain?

I have recently picked up a project from a developer who has left the company. He has made use of the GNU ARM Toolchain v13.3.1.  The customer is now asking exactly which libraries in the toolchain are linked into the binary which we have provided, and specifically, which versions.

I have found from examining the map file that the only library files being used are libc.a and libgcc.a. However I cannot find a way of determining which of these libraries are being used.  Is this information publicly available?  Could someone direct me to a page on the website which lists the version numbers of the libraries in this version of the toolchain?  Or is there any convenient way of finding out?

We are working in a windows environment, and this project was built in STM32CubeIDE.

Thanks