Nix: revert to using CMake, drop ninja

CMakeLists.txt

@@ -216,10 +216,13 @@ set(CPACK_PROJECT_NAME ${PROJECT_NAME})
 set(CPACK_PROJECT_VERSION ${PROJECT_VERSION})
 include(CPack)
 
-message(STATUS "Setting precompiled headers")
-
-target_precompile_headers(Hyprland PRIVATE
-                          $<$<COMPILE_LANGUAGE:CXX>:src/pch/pch.hpp>)
+if(CMAKE_DISABLE_PRECOMPILE_HEADERS)
+  message(STATUS "Not using precompiled headers")
+else()
+  message(STATUS "Setting precompiled headers")
+  target_precompile_headers(Hyprland PRIVATE
+                            $<$<COMPILE_LANGUAGE:CXX>:src/pch/pch.hpp>)
+endif()
 
 message(STATUS "Setting link libraries")
 

nix/cmake-version.patch

@@ -0,0 +1,10 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 6fdf98db..d8424d91 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -1,4 +1,4 @@
+-cmake_minimum_required(VERSION 3.30)
++cmake_minimum_required(VERSION 3.27)
+
+ # Get version
+ file(READ "${CMAKE_SOURCE_DIR}/VERSION" VER_RAW)

nix/default.nix

@@ -5,9 +5,7 @@
   pkg-config,
   pkgconf,
   makeWrapper,
-  meson,
   cmake,
-  ninja,
   aquamarine,
   binutils,
   cairo,
@@ -53,7 +51,7 @@
   inherit (lib.attrsets) mapAttrsToList;
   inherit (lib.lists) flatten concatLists optional optionals;
   inherit (lib.sources) cleanSourceWith cleanSource;
-  inherit (lib.strings) hasSuffix makeBinPath optionalString mesonBool mesonEnable;
+  inherit (lib.strings) cmakeBool hasSuffix makeBinPath optionalString;
 
   adapters = flatten [
     stdenvAdapters.useMoldLinker
@@ -76,6 +74,14 @@ in
         src = cleanSource ../.;
       };
 
+      patches = [
+        # forces GCC to use -std=c++26
+        ./stdcxx.patch
+
+        # Nix does not have CMake 3.30 yet, so override the minimum version
+        ./cmake-version.patch
+      ];
+
       postPatch = ''
         # Fix hardcoded paths to /usr installation
         sed -i "s#/usr#$out#" src/render/OpenGL.cpp
@@ -97,9 +103,7 @@ in
         hyprwayland-scanner
         jq
         makeWrapper
-        meson
         cmake
-        ninja
         pkg-config
         python3 # for udis86
         wayland-scanner
@@ -144,22 +148,20 @@ in
         (optional withSystemd systemd)
       ];
 
-      mesonBuildType =
+      cmakeBuildType =
         if debug
-        then "debug"
-        else "release";
+        then "Debug"
+        else "RelWithDebInfo";
 
       # we want as much debug info as possible
       dontStrip = debug;
 
-      mesonFlags = flatten [
-        (mapAttrsToList mesonEnable {
-          "xwayland" = enableXWayland;
-          "legacy_renderer" = legacyRenderer;
-          "systemd" = withSystemd;
-        })
-        (mesonBool "b_pch" false)
-      ];
+      cmakeFlags = mapAttrsToList cmakeBool {
+        "NO_XWAYLAND" = !enableXWayland;
+        "LEGACY_RENDERER" = legacyRenderer;
+        "NO_SYSTEMD" = !withSystemd;
+        "CMAKE_DISABLE_PRECOMPILE_HEADERS" = true;
+      };
 
       postInstall = ''
         ${optionalString wrapRuntimeDeps ''

nix/stdcxx.patch

@@ -0,0 +1,12 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index cfbd431f..73e8e0c2 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -64,6 +64,7 @@ endif()
+ include_directories(. "src/" "subprojects/udis86/" "protocols/")
+ set(CMAKE_CXX_STANDARD 26)
+ add_compile_options(
++  -std=c++26
+   -Wall
+   -Wextra
+   -Wno-unused-parameter