Telling gcc directly to link a library statically

Use -l: instead of -l. For example -l:libXYZ.a to link with libXYZ.a. Notice the lib and .a are written out, as opposed to -lXYZ which would auto-expand to libXYZ.so/libXYZ.a.

It is an option of the GNU ld linker:

-l namespec … If namespec is of the form :filename, ld will search the library path for a file called filename, otherwise it will search the library path for a file called libnamespec.a. … on ELF … systems, ld will search a directory for a library called libnamespec.so before searching for one called libnamespec.a. … Note that this behavior does not apply to :filename, which always specifies a file called filename.”

(Since binutils 2.18)

Note that this only works with the GNU linker. If your ld isn’t the GNU one you’re out of luck.