`X11-xft` builds under Cabal 3.6, but not Cabal 3.8

[elldritch]

Here's a repository containing a project whose cabal build succeeds using Cabal 3.6, but not Cabal 3.8, complaining that:

$ cabal v2-build --minimize-conflict-set
Resolving dependencies...
Error: cabal: Could not resolve dependencies:
[__0] trying: cabal-xft-repro-0.0.1.0 (user goal)
[__1] trying: xmobar-0.44.2 (dependency of cabal-xft-repro)
[__2] rejecting: xmobar:-with_xft (constraint from project config
/root/cabal.project requires opposite flag selection)
[__2] trying: xmobar:+with_xft
[__3] next goal: X11-xft (dependency of xmobar +with_xft)
[__3] rejecting: X11-xft-0.3.4, X11-xft-0.3.3, X11-xft-0.3.1, X11-xft-0.3
(conflict: pkg-config package xft-any, not found in the pkg-config database)
[__3] trying: X11-xft-0.2
[__4] next goal: base (dependency of cabal-xft-repro)
[__4] rejecting: base-4.14.3.0/installed-4.14.3.0 (conflict: X11-xft =>
base<4.4)
[__4] skipping: base-4.17.0.0, base-4.16.3.0, base-4.16.2.0, base-4.16.1.0,
base-4.16.0.0, base-4.15.1.0, base-4.15.0.0, base-4.14.3.0, base-4.14.2.0,
base-4.14.1.0, base-4.14.0.0, base-4.13.0.0, base-4.12.0.0, base-4.11.1.0,
base-4.11.0.0, base-4.10.1.0, base-4.10.0.0, base-4.9.1.0, base-4.9.0.0,
base-4.8.2.0, base-4.8.1.0, base-4.8.0.0, base-4.7.0.2, base-4.7.0.1,
base-4.7.0.0, base-4.6.0.1, base-4.6.0.0, base-4.5.1.0, base-4.5.0.0,
base-4.4.1.0, base-4.4.0.0 (has the same characteristics that caused the
previous version to fail: excluded by constraint '<4.4' from 'X11-xft')
[__4] rejecting: base-4.3.1.0, base-4.3.0.0, base-4.2.0.2, base-4.2.0.1,
base-4.2.0.0, base-4.1.0.0, base-4.0.0.0, base-3.0.3.2, base-3.0.3.1
(constraint from non-upgradeable package requires installed instance)
[__4] fail (backjumping, conflict set: X11-xft, base, cabal-xft-repro)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: xmobar, cabal-xft-repro, base,
X11-xft, xmobar:with_xft

Oddly, I can reproduce this issue on both my Arch Linux laptop and desktop, but I can't get the issue to reproduce in a Docker container, even though the packages installed on my host machines are a superset of the packages installed in the container.

I've also checked that:

• libxft is installed.
• pkg-config is working.
• pkg-config --modversion xft works.
• pkg-config --list-all contains xft.
• /usr/lib/pkgconfig/xft.pc exists and is valid.

I suspect this might be related to #8455 or #8494

I'm running GHC 9.0.2 installed using GHCup 0.1.18.0.

[gbaz]

Can you check if pkg-config --list-all contains any packages for which modversion fails?

[georgefst]

I'm seeing the same issue with evdev, which unsurprisingly relies on libevdev. I'm on Manjaro Linux (based on Arch).

Can you check if pkg-config --list-all contains any packages for which modversion fails?

Yes, precisely one package:

$ for pkg in $(pkg-config --list-all | while read p ; do echo $p | cut -f 1 -d ' ' ; done) ; do pkg-config --modversion $pkg ; done > /dev/null
Package libxfce4ui-1 was not found in the pkg-config search path.
Perhaps you should add the directory containing `libxfce4ui-1.pc'
to the PKG_CONFIG_PATH environment variable
Package 'libxfce4ui-1', required by 'libxfce4sensors-1.0', not found

So this looks a lot like #8494. But I've compiled #8496 and that still gives me the same error.

[elldritch]

Can you check if pkg-config --list-all contains any packages for which modversion fails?

Yup, here's my output. Similarly, one package is broken:

$ for pkg in $(pkg-config --list-all | while read p ; do echo $p | cut -f 1 -d ' ' ; done) ; do pkg-config --modversion $pkg ; done > /dev/null
Package gobject-introspection-1.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `gobject-introspection-1.0.pc'
to the PKG_CONFIG_PATH environment variable
Package 'gobject-introspection-1.0', required by 'libpeas-1.0', not found
Package gobject-introspection-1.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `gobject-introspection-1.0.pc'
to the PKG_CONFIG_PATH environment variable
Package 'gobject-introspection-1.0', required by 'libpeas-1.0', not found

[gbaz]

So this looks a lot like #8494. But I've compiled #8496 and that still gives me the same error.

@georgefst apologies. there was a typo disrupting the logic in that PR. give it another shot!

[georgefst]

So this looks a lot like #8494. But I've compiled #8496 and that still gives me the same error.

@georgefst apologies. there was a typo disrupting the logic in that PR. give it another shot!

Works! Awesome, thanks.

[gbaz]

Great. Closing this in favor of #8494