Allow to disable LTO for test cases separately

.ci/build_windows.bat

@@ -53,7 +53,7 @@ cmake -G Ninja -DCMAKE_TOOLCHAIN_FILE="%MUMBLE_ENVIRONMENT_TOOLCHAIN%" -DVCPKG_T
       -DIce_HOME="%MUMBLE_ENVIRONMENT_PATH%\installed\%MUMBLE_ENVIRONMENT_TRIPLET%" ^
       -DCMAKE_C_COMPILER=cl.exe -DCMAKE_CXX_COMPILER=cl.exe ^
       -DCMAKE_BUILD_TYPE=Release -DCMAKE_UNITY_BUILD=ON -DBUILD_NUMBER=%BUILD_NUMBER% ^
-      -Dpackaging=ON -Dtests=ON -Dstatic=ON -Dsymbols=ON -Dasio=ON -Dg15=ON ^
+      -Dpackaging=ON -Dtests=ON -Dstatic=ON -Dsymbols=ON -Dasio=ON -Dg15=ON -Dtest-lto=OFF ^
       -Ddisplay-install-paths=ON -Ddatabase-sqlite-tests=ON -Ddatabase-mysql-tests=ON -Ddatabase-postgresql-tests=ON ^
 	  -Delevation=%MUMBLE_USE_ELEVATION% %MUMBLE_SOURCE_REPOSITORY%
 

docs/dev/build-instructions/cmake_options.md

@@ -264,6 +264,11 @@ Build static binaries.
 Build binaries in a way that allows easier debugging.
 (Default: OFF)
 
+### test-lto
+
+Whether to use LTO when building test cases
+(Default: ${lto})
+
 ### tests
 
 Build tests.

src/tests/CMakeLists.txt

@@ -8,7 +8,9 @@ include(project-utils)
 find_pkg(Qt6 COMPONENTS Test REQUIRED)
 
 option(online-tests "Whether or not tests that need a working internet connection should be included" OFF)
+option(test-lto "Whether to use LTO when building test cases" ${lto})
 
+set(CMAKE_INTERPROCEDURAL_OPTIMIZATION ${test-lto})
 
 # Set output directory
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/tests")