In 724e833ea2, I was a little too aggressive in enabling these flags.
Many don’t work in gcc, and we should probably avoid settings them
widely. This makes those flags optional on isclang
A few months ago I moved these patches to the new debian alsa instance [1], but
it looks like their `sha256`s on the tag at the remote have changed again.
It doesn't appear that debian's source remote is stable in the way we need it to
be; let's just vendor the patches to avoid future issues.
[1] https://github.com/NixOS/nixpkgs/pull/41769
Another broken URL related to: https://github.com/NixOS/nixpkgs/issues/39927
Note that the patch file has legitimately changed, because ~4 months ago Debian
replaced their CVE security fix with a newer version that fixes some additional
bugs: d6fd3b3734
We still do mirror the patch (I think), as `nix-build -Q -A p7zip.patches`
downloaded it on my machine. I verified that only the diff headers differ;
it's still better to have another working download and Fedora's URLs are
less likely to disappear than Debian's.
/cc #27075.
The debian source for this patch file has gone away, rendering this derivation
unbuildable from scratch.
This change updates the URL to a src.fedoraproject.org location that is still
serving a p7zip patch. This file is not the same bytewise, so I'm also updating
the hash; I didn't manage to find a location still serving a file with the
original hash, and my best guess is that this one is functionally equivalent.
