Having thread pool as its own singleton in the library meant that each
kiface had its own threadpool, leading to many multiples of the threads
being started. Placing a singleton class in PGM_BASE ensures that all
kifaces use the same thread pool.
The singleton class can be extended to provide single instance
guarantee for any element across kifaces
The link maps were actually disabled by default before
912f1d5cecdc7d14df09d7e9a78e0aa75760b75d, and required KICAD_MAKE_LINK_MAPS
to be provided to enable them. So switch back to disabling them by
default.
Also, The lld linker is unable to accept a single dash cref option, while
ld and gold can. Instead, use the double dash version that is supported
by all three.
xref: https://github.com/llvm/llvm-project/issues/60932
Co-authored-by: aris-kimi <aris_kimi@hotmail.com>
Co-authored-by: Ian McInerney <ian.s.mcinerney@ieee.org>
ADDED: with cmake KICAD_MACOSX_APP_BUNDLE option the user can disable
the macOS app bundle creation when compiling on macOS. This permit to
use/install KiCad like any other *nix platform (/usr/bin, /usr/share,
ecc.). By default, cmake build the app bundle.
