As the maintainer of Magit I opt-in to `package.el' not messing
up the builds of this package and its dependencies.
(require 'cl-lib)
(require 'async)
-(defcustom async-bytecomp-allowed-packages '(async helm helm-core helm-ls-git helm-ls-hg)
+(defcustom async-bytecomp-allowed-packages
+ '(async helm helm-core helm-ls-git helm-ls-hg magit)
"Packages in this list will be compiled asynchronously by `package--compile'.
All the dependencies of these packages will be compiled async too,
so no need to add dependencies to this list.