i fully understand that full support for pragma(lib) is nearly impossible. but
can we at least add CLI flag that will instruct compiler to write all libraries
from that pragma to some file during compilation?

this way build tools can pass something like
"-fwrite-pragma-lib-to=linklibssmth" and then invoke linker with
-Wl,@linklibssmth

build tool can create this files for each compiled module and then pass 'em all
to linker.

this is far from full supporting of pragma(lib), but it at least will allow
build tools to extract, cache and use that info without built-in (or external)
D parser.

and gdc should do it during 'real' compilation to avoid execing gdc second time
just to obtain this info. we always can do 'gdc -c -o /dev/null' if we want
only info w/o object files.