python3Packages.qdldl: fix for CMake v4

by properly using our qdldl, and, while here, fixing its CMake exports

pkgs/by-name/qd/qdldl/package.nix

@@ -16,6 +16,13 @@ stdenv.mkDerivation (finalAttrs: {
     hash = "sha256-pRlxqy5G8mxKXTIn4ruV/95TzpzNB/ArJX+WrEJRqW4=";
   };
 
+  # fix abs dir concatenation
+  postPatch = ''
+    substituteInPlace CMakeLists.txt --replace-fail \
+      "$<INSTALL_PREFIX>/$""{CMAKE_INSTALL_INCLUDEDIR}" \
+      "$""{CMAKE_INSTALL_INCLUDEDIR}"
+  '';
+
   nativeBuildInputs = [
     cmake
   ];

pkgs/development/python-modules/qdldl/default.nix

@@ -2,12 +2,14 @@
   lib,
   buildPythonPackage,
   fetchFromGitHub,
+  replaceVars,
   cmake,
   numpy,
   pybind11,
   setuptools,
   scipy,
   pytestCheckHook,
+  qdldl,
 }:
 
 buildPythonPackage rec {
@@ -22,6 +24,13 @@ buildPythonPackage rec {
     hash = "sha256-XHdvYWORHDYy/EIqmlmFQZwv+vK3I+rPIrvcEW1JyIw=";
   };
 
+  # use up-to-date qdldl for CMake v4
+  patches = [
+    (replaceVars ./use-qdldl.patch {
+      inherit qdldl;
+    })
+  ];
+
   dontUseCmakeConfigure = true;
 
   build-system = [
@@ -36,6 +45,10 @@ buildPythonPackage rec {
     scipy
   ];
 
+  propagatedBuildInputs = [
+    qdldl
+  ];
+
   pythonImportsCheck = [ "qdldl" ];
   nativeCheckInputs = [ pytestCheckHook ];
 

pkgs/development/python-modules/qdldl/use-qdldl.patch

@@ -0,0 +1,93 @@
+From 0293de5a5bd209386b3c021ee661e85eee1985a9 Mon Sep 17 00:00:00 2001
+From: Guilhem Saurel <guilhem.saurel@laas.fr>
+Date: Sun, 21 Sep 2025 14:55:32 +0200
+Subject: [PATCH] Use up-to-date qdldl for CMake v4
+
+---
+ c/CMakeLists.txt                   | 5 +++--
+ c/amd/include/SuiteSparse_config.h | 2 +-
+ c/amd/include/perm.h               | 2 +-
+ cpp/qdldl.hpp                      | 2 +-
+ setup.py                           | 3 ++-
+ 5 files changed, 8 insertions(+), 6 deletions(-)
+
+diff --git a/c/CMakeLists.txt b/c/CMakeLists.txt
+index 728204d..df15d84 100644
+--- a/c/CMakeLists.txt
++++ b/c/CMakeLists.txt
+@@ -12,7 +12,7 @@ set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+ 
+ set(LIBRARY_OUTPUT_PATH ${PROJECT_BINARY_DIR}/out)
+ 
+-add_subdirectory(qdldl EXCLUDE_FROM_ALL)
++find_package(qdldl REQUIRED CONFIG)
+ 
+ set(
+     amd_src
+@@ -37,7 +37,8 @@ set(
+ 
+ 
+ # Add QDLDL+AMD library
+-add_library(qdldlamd STATIC ${amd_src} $<TARGET_OBJECTS:qdldlobject>)
++add_library(qdldlamd STATIC ${amd_src})
++target_link_libraries(qdldlamd qdldl::qdldl)
+ target_include_directories(qdldlamd PRIVATE
+ 	                   ${CMAKE_CURRENT_SOURCE_DIR}/amd/include
+ 	                   ${CMAKE_CURRENT_SOURCE_DIR}/qdldl/include
+diff --git a/c/amd/include/SuiteSparse_config.h b/c/amd/include/SuiteSparse_config.h
+index ea3cea4..19ac8df 100644
+--- a/c/amd/include/SuiteSparse_config.h
++++ b/c/amd/include/SuiteSparse_config.h
+@@ -42,7 +42,7 @@
+ extern "C" {
+ #endif
+ 
+-#include "qdldl_types.h"
++#include "qdldl/qdldl_types.h"
+ #define DLONG
+ typedef QDLDL_float c_float;
+ 
+diff --git a/c/amd/include/perm.h b/c/amd/include/perm.h
+index 16c2617..841abe1 100644
+--- a/c/amd/include/perm.h
++++ b/c/amd/include/perm.h
+@@ -2,7 +2,7 @@
+ extern "C" {
+ # endif // ifdef __cplusplus
+ 
+-#include "qdldl_types.h"
++#include "qdldl/qdldl_types.h"
+ 
+ /**
+  * C = A(p,p)= PAP' where A and C are symmetric the upper part stored;
+diff --git a/cpp/qdldl.hpp b/cpp/qdldl.hpp
+index 83b4970..1a7b5d1 100644
+--- a/cpp/qdldl.hpp
++++ b/cpp/qdldl.hpp
+@@ -1,5 +1,5 @@
+ // Source code for QDLDL, AMD and permutations
+-#include "qdldl/include/qdldl.h"
++#include "qdldl/qdldl.h"
+ #include "amd/include/amd.h"
+ #include "amd/include/perm.h"
+ #include <stdexcept>
+diff --git a/setup.py b/setup.py
+index edb50ed..c0e4c23 100644
+--- a/setup.py
++++ b/setup.py
+@@ -97,10 +97,11 @@ class build_ext_qdldl(build_ext):
+ qdldl = Extension('qdldl',
+                   sources=glob(os.path.join('cpp', '*.cpp')),
+                   include_dirs=[os.path.join('c'),
+-                                os.path.join('c', 'qdldl', 'include'),
++                                "@qdldl@/include",
+                                 get_pybind_include(),
+                                 get_pybind_include(user=False)],
+                   language='c++',
++                  extra_link_args=['-lqdldl'],
+                   extra_compile_args=compile_args + ['-std=c++11'],
+                   extra_objects=[qdldl_lib])
+ 
+-- 
+2.51.0
+

pkgs/top-level/python-packages.nix

@@ -15469,7 +15469,7 @@ self: super: with self; {
 
   qdarkstyle = callPackage ../development/python-modules/qdarkstyle { };
 
-  qdldl = callPackage ../development/python-modules/qdldl { };
+  qdldl = callPackage ../development/python-modules/qdldl { inherit (pkgs) qdldl; };
 
   qdrant-client = callPackage ../development/python-modules/qdrant-client { };