johnb I'm positive you're ignoring a crucial feature of pkgsrc, which is make (build) options. I'm surprised nobody pointed this out so far.
Anyway, many packages provide alternative sets of compile flags for one to enable/disable at will if they're not satisfied with the options enabled by default in the binary package. I'm under the impression it's a common practice among packagers to keep pkgsrc default build flags as minimal and conservative as possible (as far as this does not break usability). If an important tunable feature is available as a make option, which is true under most circumstances, you do not need to patch the package in order to enable it. You can use make show-options
in the category/package dir to display available options, then edit your /etc/mk.conf
accordingly in order to enable them.
On vanilla pkgsrc-2019Q4, I have:
$ cd /usr/pkgsrc/wm/fvwm && make show-options
Any of the following general options may be selected:
debug Enable debugging facilities in the package.
fribidi Enable BIDI support using fribidi.
gtk Enable support for GTK.
rplay
xcursor Enable Xcursor support.
xft2 Enable Xft support.
xrender Enable Xrender support.
These options are enabled by default:
These options are currently enabled:
You can select which build options to use by setting PKG_DEFAULT_OPTIONS
or PKG_OPTIONS.fvwm.
Now, I can enable Xft2, Xcursor and Xrender by adding a suitable _OPTIONS entry in my mk.conf (done it for years, FVWM user as well):
$ echo "PKG_OPTIONS.fvwm=xcursor xft2 xrender" >> /etc/mk.conf
Now, let's check everything is in place:
$ pwd
/usr/pkgsrc/wm/fvwm
$ make show-options
These options are currently enabled:
xcursor xft2 xrender
running make install
shall therefore compile and install FVWM2 with Xft as expected.
The official wiki and man pages are your best friend and support channel. Please, make sure you have a look at how to use pkg options with pkgsrc
Cheers!
By the way @johnb , you may be interested in my FVWM guide