build system: support module local definitions

This introduces a new helper function,
qt_internal_add_repo_local_defines and makes use of it in
qt_internal_add_{module,test,executable,benchmark,plugin}. That function
checks whether QT_EXTRA_INTERNAL_TARGET_DEFINES is set. If it is, the
defines listed in there will be aded to all targets passed to the
functions mentioned above.

The intended usage is that QT_EXTRA_INTERNAL_TARGET_DEFINES gets set
in the repository local .cmake.conf. This allows e.g. opting in to
source incompatible changes in leaf modules (as long as those are
guarded by some define).

Pick-to: 6.2 6.3
Fixes: QTBUG-101640
Change-Id: I06c3693ee69f46e95a48de724621f0c97e7cc3a8
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

cmake/QtExecutableHelpers.cmake

@@ -70,6 +70,9 @@ function(qt_internal_add_executable name)
     endif()
 
     qt_set_common_target_properties(${name})
+
+    qt_internal_add_repo_local_defines(${name})
+
     if(ANDROID)
         # The above call to qt_set_common_target_properties() sets the symbol
         # visibility to hidden, but for Android, we need main() to not be hidden

cmake/QtModuleHelpers.cmake

@@ -510,6 +510,8 @@ function(qt_internal_add_module target)
         list(APPEND arg_LIBRARIES Qt::PlatformModuleInternal)
     endif()
 
+    qt_internal_add_repo_local_defines("${target}")
+
     qt_internal_extend_target("${target}"
         ${header_module}
         SOURCES ${arg_SOURCES}

cmake/QtPluginHelpers.cmake

@@ -329,6 +329,8 @@ function(qt_internal_add_plugin target)
         DISABLE_AUTOGEN_TOOLS ${arg_DISABLE_AUTOGEN_TOOLS}
     )
 
+    qt_internal_add_repo_local_defines("${target}")
+
     qt_internal_set_exceptions_flags("${target}" ${arg_EXCEPTIONS})
 
 

cmake/QtTargetHelpers.cmake

@@ -874,3 +874,19 @@ function(qt_internal_undefine_global_definition target)
         set_target_properties(${target} PROPERTIES "${undef_property_name}" TRUE)
     endforeach()
 endfunction()
+
+# This function adds any defines which are local to the current repository (e.g. qtbase,
+# qtmultimedia). Those can be defined in the corresponding .cmake.conf file via
+# QT_EXTRA_INTERNAL_TARGET_DEFINES. QT_EXTRA_INTERNAL_TARGET_DEFINES accepts a list of definitions.
+# The definitions are passed to target_compile_definitions, which means that values can be provided
+# via the FOO=Bar syntax
+# This does nothing for interface targets
+function(qt_internal_add_repo_local_defines target)
+    get_target_property(type "${target}" TYPE)
+    if (${type} STREQUAL "INTERFACE_LIBRARY")
+        return()
+    endif()
+    if(DEFINED QT_EXTRA_INTERNAL_TARGET_DEFINES)
+        target_compile_definitions("${target}" PRIVATE ${QT_EXTRA_INTERNAL_TARGET_DEFINES})
+    endif()
+endfunction()

cmake/QtTestHelpers.cmake

@@ -33,6 +33,9 @@ function(qt_internal_add_benchmark target)
         ${exec_args}
     )
 
+
+    qt_internal_add_repo_local_defines(${target})
+
     # Disable the QT_NO_NARROWING_CONVERSIONS_IN_CONNECT define for benchmarks
     qt_internal_undefine_global_definition(${target} QT_NO_NARROWING_CONVERSIONS_IN_CONNECT)
 
@@ -264,6 +267,8 @@ function(qt_internal_add_test name)
             DISABLE_AUTOGEN_TOOLS ${arg_DISABLE_AUTOGEN_TOOLS}
         )
 
+        qt_internal_add_repo_local_defines(${name})
+
         # Disable the QT_NO_NARROWING_CONVERSIONS_IN_CONNECT define for tests
         qt_internal_undefine_global_definition(${name} QT_NO_NARROWING_CONVERSIONS_IN_CONNECT)