From 50df715912b76362a07810b67b8586298c9bcf02 Mon Sep 17 00:00:00 2001
From: Drew Parsons <dparsons@debian.org>
Date: Fri, 30 Jan 2026 11:50:41 +0100
Subject: [PATCH] add debian patch findEXPAT_version_fix_MR12826.patch

applies upstream MR#12826 to fix expat version handling

Closes: #1050506
---
 debian/changelog                              |  7 ++
 .../findEXPAT_version_fix_MR12826.patch       | 76 +++++++++++++++++++
 debian/patches/series                         |  1 +
 3 files changed, 84 insertions(+)
 create mode 100644 debian/patches/findEXPAT_version_fix_MR12826.patch

diff --git a/debian/changelog b/debian/changelog
index 90b17b48d..53ee3fbfa 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,10 @@
+vtk9 (9.5.2+dfsg3-5) UNRELEASED; urgency=medium
+
+  * debian patch findEXPAT_version_fix_MR12826.patch applies upstream
+    MR#12826 to fix expat version handling. Closes: #1050506
+
+ -- Drew Parsons <dparsons@debian.org>  Fri, 30 Jan 2026 11:47:03 +0100
+
 vtk9 (9.5.2+dfsg3-4) unstable; urgency=medium
 
   * Team upload.
diff --git a/debian/patches/findEXPAT_version_fix_MR12826.patch b/debian/patches/findEXPAT_version_fix_MR12826.patch
new file mode 100644
index 000000000..6c072d7ee
--- /dev/null
+++ b/debian/patches/findEXPAT_version_fix_MR12826.patch
@@ -0,0 +1,76 @@
+From b4d87554cf82db109b21e905fb57df05df8adbdc Mon Sep 17 00:00:00 2001
+From: Julien Schueller <schueller@phimeca.com>
+Date: Mon, 19 Jan 2026 14:49:34 +0100
+Subject: [PATCH] CMake: Fix EXPAT version warning
+
+Closes #19679
+---
+ CMake/FindEXPAT.cmake           | 11 ++++++-----
+ ThirdParty/expat/CMakeLists.txt |  7 ++++---
+ 2 files changed, 10 insertions(+), 8 deletions(-)
+
+diff --git a/CMake/FindEXPAT.cmake b/CMake/FindEXPAT.cmake
+index 00b160a4952..5dda968d005 100644
+--- a/CMake/FindEXPAT.cmake
++++ b/CMake/FindEXPAT.cmake
+@@ -43,25 +43,26 @@ if (EXPAT_INCLUDE_DIR AND EXISTS "${EXPAT_INCLUDE_DIR}/expat.h")
+     file(STRINGS "${EXPAT_INCLUDE_DIR}/expat.h" expat_version_str
+          REGEX "^#[\t ]*define[\t ]+XML_(MAJOR|MINOR|MICRO)_VERSION[\t ]+[0-9]+$")
+ 
+-    unset(EXPAT_VERSION_STRING)
++    unset(EXPAT_VERSION)
+     foreach(VPART MAJOR MINOR MICRO)
+         foreach(VLINE ${expat_version_str})
+             if(VLINE MATCHES "^#[\t ]*define[\t ]+XML_${VPART}_VERSION[\t ]+([0-9]+)$")
+                 set(EXPAT_VERSION_PART "${CMAKE_MATCH_1}")
+-                if(EXPAT_VERSION_STRING)
+-                    string(APPEND EXPAT_VERSION_STRING ".${EXPAT_VERSION_PART}")
++                if(EXPAT_VERSION)
++                    string(APPEND EXPAT_VERSION ".${EXPAT_VERSION_PART}")
+                 else()
+-                    set(EXPAT_VERSION_STRING "${EXPAT_VERSION_PART}")
++                    set(EXPAT_VERSION "${EXPAT_VERSION_PART}")
+                 endif()
+             endif()
+         endforeach()
+     endforeach()
++    set(EXPAT_VERSION_STRING ${EXPAT_VERSION})
+ endif ()
+ 
+ include(FindPackageHandleStandardArgs)
+ FIND_PACKAGE_HANDLE_STANDARD_ARGS(EXPAT
+                                   REQUIRED_VARS EXPAT_LIBRARY EXPAT_INCLUDE_DIR
+-                                  VERSION_VAR EXPAT_VERSION_STRING)
++                                  VERSION_VAR EXPAT_VERSION)
+ 
+ # Copy the results to the output variables and target.
+ if(EXPAT_FOUND)
+diff --git a/ThirdParty/expat/CMakeLists.txt b/ThirdParty/expat/CMakeLists.txt
+index a08980c8442..90e3ce28eff 100644
+--- a/ThirdParty/expat/CMakeLists.txt
++++ b/ThirdParty/expat/CMakeLists.txt
+@@ -16,7 +16,8 @@ vtk_module_third_party(
+     PACKAGE EXPAT
+     VERSION 2.2.1 # absolute minimun, correspending to version in macOS 10.13
+     TARGETS EXPAT::EXPAT
+-    STANDARD_INCLUDE_DIRS)
++    STANDARD_INCLUDE_DIRS
++    USE_VARIABLES EXPAT_VERSION)
+ 
+ include(vtkDetectLibraryType)
+ vtk_detect_library_shared(vtkexpat EXPAT::EXPAT)
+@@ -42,9 +43,9 @@ vtk_module_install_headers(
+ if(NOT DEFINED ENV{DASHBOARD_TEST_FROM_CTEST})
+   # Check for deprecated versions of expat
+   set(expat_deprecated_version "2.6.3")
+-  if(VTK_MODULE_USE_EXTERNAL_vtkexpat AND EXPAT_VERSION_STRING VERSION_LESS expat_deprecated_version)
++  if(VTK_MODULE_USE_EXTERNAL_vtkexpat AND EXPAT_VERSION VERSION_LESS expat_deprecated_version)
+     message(DEPRECATION
+-      "External expat ${EXPAT_VERSION_STRING} is less than ${expat_deprecated_version} "
++      "External expat ${EXPAT_VERSION} is less than ${expat_deprecated_version} "
+       "and (may) have known vulnerabilities. Consider upgrading.")
+   endif()
+ endif()
+-- 
+GitLab
+
diff --git a/debian/patches/series b/debian/patches/series
index 1cd5fcbf3..70678eba9 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -11,3 +11,4 @@
 99_fix_ftbfs.patch
 100_add_missing_gl_header.patch
 121_add_support_for_loong64.patch
+findEXPAT_version_fix_MR12826.patch
-- 
2.30.2