Source: https://invent.kde.org/graphics/krita/-/merge_requests/2386

From c2bcea11d461729c6c156d43452d289d895d200b Mon Sep 17 00:00:00 2001
From: Joshua Goins <josh@redstrate.com>
Date: Sat, 11 Oct 2025 22:10:29 -0400
Subject: [PATCH 1/2] Manually define Qt6Gui_PRIVATE_INCLUDE_DIRS CMake
 variable

Previously Krita was dependent on an implementation detail of Qt's CMake
module, which has a history of breaking. For reference, Krita no longer
builds on Qt dev because they shuffled things around again!

Most notably, the variable Krita used isn't available anymore - so we
need to manually re-create it so the other parts of the CMakeLists
will work. The more correct and reliable solution would be to use the
Qt6Private target itself, but Krita needs to selectively use the private
headers for compilation speed reasons, so I decided to add a workaround
for now.
---
 CMakeLists.txt | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b0f27a21ce8..c822d86b62e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -543,12 +543,33 @@ if (QT_MAJOR_VERSION STREQUAL "6")
         REQUIRED COMPONENTS
         ColorScheme
     )
+
+    # Qt 6.10 has split this into it's own CMake module, it's no longer included with Gui
+    if (Qt6Gui_VERSION VERSION_GREATER_EQUAL "6.10.0")
+        find_package(Qt6GuiPrivate ${REQUIRED_QT_VERSION} REQUIRED NO_MODULE)
+        get_target_property(Qt6Gui_PRIVATE_INCLUDE_DIRS Qt6::GuiPrivate INTERFACE_INCLUDE_DIRECTORIES)
+
+        # QtGui depends on private headers form QtCore as well
+        find_package(Qt6CorePrivate ${REQUIRED_QT_VERSION} REQUIRED NO_MODULE)
+        get_target_property(Qt6Core_PRIVATE_INCLUDE_DIRS Qt6::CorePrivate INTERFACE_INCLUDE_DIRECTORIES)
+
+        # Currently we depend on the Qt6Gui_PRIVATE_INCLUDE_DIRS variable to selectively include
+        # the needed headers, but it will fail to compile in 6.10 since the private headers exist
+        # in separate directories. So we'll just shove them into the variable we expect for now.
+        list(APPEND Qt6Gui_PRIVATE_INCLUDE_DIRS ${Qt6Core_PRIVATE_INCLUDE_DIRS})
+    endif()
 endif()
 
 set(HAVE_WAYLAND FALSE)
 if (TARGET Qt::WaylandClient)
     message(STATUS "Found Qt::WaylandClient, enabling kritawayland platform")
     set(HAVE_WAYLAND TRUE)
+
+    # Qt 6.10 has split the private module, see above for a better explanation
+    if (Qt6Gui_VERSION VERSION_GREATER_EQUAL "6.10.0")
+        find_package(Qt6WaylandClientPrivate ${REQUIRED_QT_VERSION} REQUIRED NO_MODULE)
+        get_target_property(Qt6WaylandClient_PRIVATE_INCLUDE_DIRS Qt6::WaylandClientPrivate INTERFACE_INCLUDE_DIRECTORIES)
+    endif()
 endif()
 
 option(KRITA_USE_SURFACE_COLOR_MANAGEMENT_API "Use per-surface color management API (e.g. when using Wayland)" ${HAVE_WAYLAND})
-- 
GitLab


From 64a665a1917657c8b0ad5238ccd0539192111bad Mon Sep 17 00:00:00 2001
From: Joshua Goins <josh@redstrate.com>
Date: Sat, 11 Oct 2025 22:10:41 -0400
Subject: [PATCH 2/2] Add missing QElapsedTimer includes in tests

Some upstream header that previously included QElapsedTimer no longer
does in Qt 6.10, so I had to add these to get the full build to
complete.
---
 benchmarks/KisAnimationRenderingBenchmark.cpp         | 1 +
 benchmarks/kis_painter_benchmark.cpp                  | 1 +
 libs/image/tests/KisOverlayPaintDeviceWrapperTest.cpp | 2 ++
 sdk/tests/stroke_testing_utils.cpp                    | 1 +
 4 files changed, 5 insertions(+)

diff --git a/benchmarks/KisAnimationRenderingBenchmark.cpp b/benchmarks/KisAnimationRenderingBenchmark.cpp
index 808561dac07..bf21a736730 100644
--- a/benchmarks/KisAnimationRenderingBenchmark.cpp
+++ b/benchmarks/KisAnimationRenderingBenchmark.cpp
@@ -6,6 +6,7 @@
 
 #include "KisAnimationRenderingBenchmark.h"
 
+#include <QElapsedTimer>
 #include <QThread>
 #include <simpletest.h>
 
diff --git a/benchmarks/kis_painter_benchmark.cpp b/benchmarks/kis_painter_benchmark.cpp
index b1a71bbfb29..ebc78092180 100644
--- a/benchmarks/kis_painter_benchmark.cpp
+++ b/benchmarks/kis_painter_benchmark.cpp
@@ -16,6 +16,7 @@ inline double drand48()
 #include <simpletest.h>
 
 #include <QtMath>
+#include <QElapsedTimer>
 #include <QImage>
 #include <kis_debug.h>
 
diff --git a/libs/image/tests/KisOverlayPaintDeviceWrapperTest.cpp b/libs/image/tests/KisOverlayPaintDeviceWrapperTest.cpp
index 33795764645..e91cc7197ea 100644
--- a/libs/image/tests/KisOverlayPaintDeviceWrapperTest.cpp
+++ b/libs/image/tests/KisOverlayPaintDeviceWrapperTest.cpp
@@ -11,6 +11,8 @@
 #include <kis_paint_device.h>
 #include "kistest.h"
 
+#include <QElapsedTimer>
+
 #include <KoColor.h>
 
 #include <kis_paint_device_debug_utils.h>
diff --git a/sdk/tests/stroke_testing_utils.cpp b/sdk/tests/stroke_testing_utils.cpp
index de71601ff46..b037e218293 100644
--- a/sdk/tests/stroke_testing_utils.cpp
+++ b/sdk/tests/stroke_testing_utils.cpp
@@ -9,6 +9,7 @@
 #include <simpletest.h>
 
 #include <QDir>
+#include <QElapsedTimer>
 #include <KoColor.h>
 #include <KoColorSpace.h>
 #include <KoColorSpaceRegistry.h>
-- 
GitLab