Add build configuration for KWin.

.kdesrc-buildrc

@@ -0,0 +1,92 @@
+# This file controls options to apply when configuring/building modules, and
+# controls which modules are built in the first place.
+# List of all options: https://docs.kde.org/trunk5/en/kdesrc-build/kdesrc-build/conf-options-table.html
+
+global
+    branch-group kf5-qt5
+
+    # Finds and includes *KDE*-based dependencies into the build.  This makes
+    # it easier to ensure that you have all the modules needed, but the
+    # dependencies are not very fine-grained so this can result in quite a few
+    # modules being installed that you didn't need.
+    include-dependencies true
+
+    # Install directory for KDE software
+    kdedir ~/kde/usr
+
+    # Directory for downloaded source code
+    source-dir ~/kde/src
+
+    # Directory to build KDE into before installing
+    # relative to source-dir by default
+    build-dir ~/kde/build
+
+#   qtdir  ~/kde/qt5 # Where to install Qt5 if kdesrc-build supplies it
+
+    cmake-options -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCXXFLAGS=-isystem /usr/include/qt5/QtCore/5.15.8 -DCMAKE_CXX_STANDARD=20 -DCMAKE_CXX_COMPILER=g++-11 -DCMAKE_C_COMPILER=gcc-11
+
+    # kdesrc-build sets 2 options which is used in options like make-options or set-env
+    # to help manage the number of compile jobs that happen during a build:
+    #
+    # 1. num-cores, which is just the number of detected CPU cores, and can be passed
+    #    to tools like make (needed for parallel build) or ninja (completely optional).
+    #
+    # 2. num-cores-low-mem, which is set to largest value that appears safe for
+    #    particularly heavyweight modules based on total memory, intended for
+    #    modules like qtwebengine
+    num-cores 4
+    num-cores-low-mem 4
+
+    # kdesrc-build can install a sample .xsession file for "Custom"
+    # (or "XSession") logins,
+    install-session-driver false
+
+    # or add a environment variable-setting script to
+    # ~/.config/kde-env-master.sh
+    install-environment-driver true
+
+    # Stop the build process on the first failure
+    stop-on-failure true
+
+    # Use a flat folder layout under ~/kde/src and ~/kde/build
+    # rather than nested directories
+    directory-layout flat
+
+    # Build with LSP support for everything that supports it
+    compile-commands-linking true
+    compile-commands-export true
+end global
+
+module kwin
+    repository kde:plasma/kwin.git
+    branch Plasma/5.27
+    # Compile for fuzzing
+    cmake-options -DCXXFLAGS=-isystem /usr/include/qt5/QtCore/5.15.8 -DCMAKE_C_COMPILER=afl-clang-lto -DCMAKE_CXX_COMPILER=afl-clang-lto++ -DCMAKE_CXX_STANDARD=20 
+    # multiple ld.lld running in LTO mode exhausts my 16 Gigs memory, so just
+    # run one at a time.
+    num-cores 1
+end module
+
+# With base options set, the remainder of the file is used to define modules to build, in the
+# desired order, and set any module-specific options.
+#
+# Modules may be grouped into sets, and this is the normal practice.
+#
+# You can include other files inline using the "include" command. We do this here
+# to include files which are updated with kdesrc-build.
+
+# Common options that should be set for some KDE modules no matter how
+# kdesrc-build finds them. Do not comment these out unless you know
+# what you are doing.
+include /home/nathan/src/kde/src/kdesrc-build/kf5-common-options-build-include
+
+# Qt and some Qt-using middleware libraries. Uncomment if your distribution's Qt
+# tools are too old but be warned that Qt take a long time to build!
+#include /home/nathan/src/kde/src/kdesrc-build/qt5-build-include
+#include /home/nathan/src/kde/src/kdesrc-build/custom-qt5-libs-build-include
+
+# KF5 and Plasma :)
+include /home/nathan/src/kde/src/kdesrc-build/kf5-qt5-build-include
+
+# To change options for modules that have already been defined, use an
+# 'options' block. See kf5-common-options-build-include for an example