diff options
Diffstat (limited to 'cmake/QtNoLinkTargetHelpers.cmake')
| -rw-r--r-- | cmake/QtNoLinkTargetHelpers.cmake | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/cmake/QtNoLinkTargetHelpers.cmake b/cmake/QtNoLinkTargetHelpers.cmake new file mode 100644 index 0000000000..debf1eb3cd --- /dev/null +++ b/cmake/QtNoLinkTargetHelpers.cmake @@ -0,0 +1,55 @@ +function(qt_create_nolink_target target dependee_target) + if(NOT TARGET "${target}") + message(FATAL_ERROR "${target} does not exist when trying to build a nolink target.") + endif() + get_target_property(type "${target}" TYPE) + if(type STREQUAL EXECUTABLE) + message(FATAL_ERROR "${target} must be a library of some kind.") + endif() + if(type STREQUAL OBJECT_LIBRARY) + message(FATAL_ERROR "${target} must not be an object library.") + endif() + + # Strip off the namespace prefix, so from Vulkan::Vulkan to Vulkan, and then append _nolink. + string(REGEX REPLACE "^.*::" "" non_prefixed_target ${target}) + set(nolink_target "${non_prefixed_target}_nolink") + + # Create the nolink interface target, assign the properties from the original target, + # associate the nolink target with the same export which contains + # the target that uses the _nolink target. + # Also create a namespaced alias of the form ${target}::${target}_nolink which is used by + # our modules. + # Also create a Qt namespaced alias target, because when exporting via install(EXPORT) + # Vulkan::Vulkan_nolink transforms into Qt6::Vulkan_nolink, and the latter needs to be an + # accessible alias for standalone tests. + if(NOT TARGET "${nolink_target}") + add_library("${nolink_target}" INTERFACE) + set(prefixed_nolink_target "${target}_nolink") + + # Whe configuring an example with qmake, if QtGui is built with Vulkan support but the + # user's machine where Qt is installed doesn't have Vulkan, qmake doesn't fail saying + # that vulkan is not installed. Instead it silently configures and just doesn't add + # the include headers. + # To mimic that in CMake, if the Vulkan CMake package is not found, we shouldn't fail + # at generation time saying that the Vulkan target does not exist. Instead check with a + # genex that the target exists to query the properties, otherwise just silently continue. + # FIXME: If we figure out that such behavior should only be applied to Vulkan, and not the + # other _nolink targets, we'll have to modify this to be configurable. + set(target_exists_genex "$<TARGET_EXISTS:${target}>") + set(props_to_set INTERFACE_INCLUDE_DIRECTORIES INTERFACE_SYSTEM_INCLUDE_DIRECTORIES + INTERFACE_COMPILE_DEFINITIONS INTERFACE_COMPILE_OPTIONS + INTERFACE_COMPILE_FEATURES) + foreach(prop ${props_to_set}) + set_target_properties( + "${nolink_target}" PROPERTIES + ${prop} $<${target_exists_genex}:$<TARGET_PROPERTY:${target},${prop}>> + ) + endforeach() + + add_library(${prefixed_nolink_target} ALIAS ${nolink_target}) + add_library("${INSTALL_CMAKE_NAMESPACE}::${nolink_target}" ALIAS ${nolink_target}) + + set(export_name "${INSTALL_CMAKE_NAMESPACE}${dependee_target}Targets") + qt_install(TARGETS ${nolink_target} EXPORT ${export_name}) + endif() +endfunction() |