chore(nix): pin coq version

Author: W95Psp

flake.nix

@@ -127,8 +127,8 @@
           };
           coverage = pkgs.callPackage ./examples/coverage {
             inherit (packages) hax;
-            inherit (pkgs) coqPackages;
             inherit craneLib;
+            coqPackages = pkgs.coqPackages_8_19;
           };
           readme-coherency =
             let src = pkgs.lib.sourceFilesBySuffices ./. [ ".md" ];

hax-lib/proof-libs/coq/coq/default.nix

@@ -1,7 +1,5 @@
-{
-  stdenv ? (import <nixpkgs> {}).stdenv,
-  coqPackages ? (import <nixpkgs> {}).coqPackages,
-}:
+{ stdenv ? (import <nixpkgs> { }).stdenv
+, coqPackages ? (import <nixpkgs> { }).coqPackages_8_19, }:
 stdenv.mkDerivation {
   name = "hax-coq-generated-core";
   src = ./generated-core;