glibmm-2.64 has this:
------
(propagated-inputs
(modify-inputs (package-propagated-inputs glibmm)
(prepend libsigc++-2)))))
------
And, the glibmm package also propagates libsigc++.
So:
------
$ guix show [email protected] | grep libsigc
dependencies: [email protected] [email protected] [email protected] [email protected]
+ [email protected] [email protected] [email protected] [email protected] [email protected]
------
It propagates both versions of libsigc++, and thus cannot be installed
into a profile. 1785 packages depend on glibmm-2.64.
This breaks synfig, which propagates glibmm, as requested in its 'synfig.pc'
pkg-config file.