Use target_compile_options instead of the hammer

Doing per target ensures that the python stuff won't get -Werror.
We can now build the python bindings and still use the developer build

CMakeLists.txt

@@ -27,13 +27,15 @@ set(PYTHON_MODULE_DIR "${CMAKE_CURRENT_LIST_DIR}/cmake/Python")
 set(CMAKE_MODULE_PATH ${ECM_MODULE_DIR} ${PYTHON_MODULE_DIR})
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
 
-if (OPTION_DEVELOPER_MODE)
-    include(ECMEnableSanitizers)
-    add_definitions(-DDOCKS_DEVELOPER_MODE -DQT_FORCE_ASSERTS)
-    if (NOT MSVC)
-        add_compile_options(-Wall -Wextra -Werror -Wno-error=deprecated-declarations)
+
+macro(set_compiler_flags targetName)
+    if (OPTION_DEVELOPER_MODE)
+        target_compile_definitions(${targetName} PRIVATE DOCKS_DEVELOPER_MODE QT_FORCE_ASSERTS)
+        if (NOT MSVC)
+            target_compile_options(${targetName} PRIVATE -Wall -Wextra -Werror -Wno-error=deprecated-declarations)
+        endif()
     endif()
-endif()
+endmacro()
 
 if (OPTION_QTQUICK)
     find_package(Qt5Quick)
@@ -49,6 +51,7 @@ if (OPTION_BUILD_PYTHON_BINDINGS)
 endif()
 
 if (OPTION_DEVELOPER_MODE)
+    include(ECMEnableSanitizers)
     if (NOT OPTION_QTQUICK)
         enable_testing()
         add_subdirectory(tests)

src/CMakeLists.txt

@@ -113,6 +113,7 @@ qt5_add_resources(RESOURCES ${CMAKE_CURRENT_SOURCE_DIR}/resources.qrc)
 
 add_library(kddockwidgets SHARED ${DOCKSLIBS_SRCS} ${DOCKS_INSTALLABLE_INCLUDES} ${RESOURCES} ${RESOURCES_QUICK})
 add_library(KDAB::kddockwidgets ALIAS kddockwidgets)
+set_compiler_flags(kddockwidgets)
 
 target_include_directories(kddockwidgets
     PUBLIC

src/private/multisplitter/CMakeLists.txt

@@ -45,6 +45,7 @@ qt5_add_resources(MULTISPLITTER_RESOURCES ${CMAKE_CURRENT_SOURCE_DIR}/multisplit
 add_library(kddockwidgets_multisplitter SHARED ${MULTISPLITTER_SRCS} ${MULTISPLITTER_RESOURCES})
 add_library(KDAB::kddockwidgets_multisplitter ALIAS kddockwidgets_multisplitter)
 target_link_libraries(kddockwidgets_multisplitter Qt5::Core Qt5::Widgets)
+set_compiler_flags(kddockwidgets_multisplitter)
 
 if (BUILD_MULTISPLITTER_QTWIDGETS_FRONTEND)
     find_package(Qt5Widgets)

src/private/multisplitter/tests/CMakeLists.txt

@@ -3,3 +3,4 @@ find_package(Qt5Test)
 
 add_executable(tst_multisplitter tst_multisplitter.cpp)
 target_link_libraries(tst_multisplitter kddockwidgets_multisplitter Qt5::Test)
+set_compiler_flags(tst_multisplitter)

tests/CMakeLists.txt

@@ -12,6 +12,7 @@ include_directories(../src/private)
 qt5_add_resources(TESTING_RESOURCES ${CMAKE_CURRENT_SOURCE_DIR}/test_resources.qrc)
 add_executable(tst_docks tst_docks.cpp ${TESTING_SRCS} ${TESTING_RESOURCES})
 target_link_libraries(tst_docks kddockwidgets kddockwidgets_multisplitter Qt5::Widgets Qt5::Test)
+set_compiler_flags(tst_docks)
 
 add_subdirectory(fuzzer)
 

tests/fuzzer/CMakeLists.txt

@@ -7,3 +7,4 @@ add_executable(fuzzer
 
 set_property(TARGET fuzzer PROPERTY CXX_STANDARD 17)
 target_link_libraries(fuzzer kddockwidgets Qt5::Widgets Qt5::Test)
+set_compiler_flags(fuzzer)