Merge topic 'fetchcontent-set-CMAKE_VERIFY_INTERFACE_HEADER_SETS' into release-3.24 2a9cc3e8e8 FetchContent: Disable header set verification for dependencies Acked-by: Kitware Robot <kwrobot@kitware.com> Merge-request: !7535
diff --git a/Help/variable/CMAKE_VERIFY_INTERFACE_HEADER_SETS.rst b/Help/variable/CMAKE_VERIFY_INTERFACE_HEADER_SETS.rst index 6f14e6f..3fb8817 100644 --- a/Help/variable/CMAKE_VERIFY_INTERFACE_HEADER_SETS.rst +++ b/Help/variable/CMAKE_VERIFY_INTERFACE_HEADER_SETS.rst
@@ -7,11 +7,33 @@ :prop_tgt:`VERIFY_INTERFACE_HEADER_SETS` property of targets when they are created. Setting it to true enables header set verification. -Projects should not set this variable, it is intended as a developer +Projects should not normally set this variable, it is intended as a developer control to be set on the :manual:`cmake(1)` command line or other equivalent methods. The developer must have the ability to enable or disable header set verification according to the capabilities of their own machine and compiler. +Verification of a dependency's header sets is not typically of interest +to developers. Therefore, :command:`FetchContent_MakeAvailable` explicitly +sets ``CMAKE_VERIFY_INTERFACE_HEADER_SETS`` to false for the duration of its +call, but restores its original value before returning. If a project brings +a dependency directly into the main build (e.g. calling +:command:`add_subdirectory` on a vendored project from a git submodule), it +should also do likewise. For example: + +.. code:: cmake + + # Save original setting so we can restore it later + set(want_header_set_verification ${CMAKE_VERIFY_INTERFACE_HEADER_SETS}) + + # Include the vendored dependency with header set verification disabled + set(CMAKE_VERIFY_INTERFACE_HEADER_SETS OFF) + add_subdirectory(...) # Vendored sources, e.g. from git submodules + + # Add the project's own sources. Restore the developer's original choice + # for whether to enable header set verification. + set(CMAKE_VERIFY_INTERFACE_HEADER_SETS ${want_header_set_verification}) + add_subdirectory(src) + By default, this variable is not set, which will result in header set verification being disabled.
diff --git a/Modules/FetchContent.cmake b/Modules/FetchContent.cmake index 27070c0..d016fb5 100644 --- a/Modules/FetchContent.cmake +++ b/Modules/FetchContent.cmake
@@ -364,6 +364,18 @@ FetchContent_Declare(other ...) FetchContent_MakeAvailable(uses_other other) + Note that :variable:`CMAKE_VERIFY_INTERFACE_HEADER_SETS` is explicitly set + to false upon entry to ``FetchContent_MakeAvailable()``, and is restored to + its original value before the command returns. Developers typically only + want to verify header sets from the main project, not those from any + dependencies. This local manipulation of the + :variable:`CMAKE_VERIFY_INTERFACE_HEADER_SETS` variable provides that + intuitive behavior. You can use variables like + :variable:`CMAKE_PROJECT_INCLUDE` or + :variable:`CMAKE_PROJECT_<PROJECT-NAME>_INCLUDE` to turn verification back + on for all or some dependencies. You can also set the + :prop_tgt:`VERIFY_INTERFACE_HEADER_SETS` property of individual targets. + .. command:: FetchContent_Populate .. note:: @@ -1814,6 +1826,13 @@ # calls will be available to the caller. macro(FetchContent_MakeAvailable) + # We must append an item, even if the variable is unset, so prefix its value. + # We will strip that prefix when we pop the value at the end of the macro. + list(APPEND __cmake_fcCurrentVarsStack + "__fcprefix__${CMAKE_VERIFY_INTERFACE_HEADER_SETS}" + ) + set(CMAKE_VERIFY_INTERFACE_HEADER_SETS FALSE) + get_property(__cmake_providerCommand GLOBAL PROPERTY __FETCHCONTENT_MAKEAVAILABLE_SERIAL_PROVIDER ) @@ -1965,10 +1984,18 @@ endif() endforeach() + # Prefix will be "__fcprefix__" + list(POP_BACK __cmake_fcCurrentVarsStack __cmake_original_verify_setting) + string(SUBSTRING "${__cmake_original_verify_setting}" + 12 -1 __cmake_original_verify_setting + ) + set(CMAKE_VERIFY_INTERFACE_HEADER_SETS ${__cmake_original_verify_setting}) + # clear local variables to prevent leaking into the caller's scope unset(__cmake_contentName) unset(__cmake_contentNameLower) unset(__cmake_contentNameUpper) unset(__cmake_providerCommand) + unset(__cmake_original_verify_setting) endmacro()
diff --git a/Tests/RunCMake/FetchContent/RunCMakeTest.cmake b/Tests/RunCMake/FetchContent/RunCMakeTest.cmake index e83c45e..a7ccf83 100644 --- a/Tests/RunCMake/FetchContent/RunCMakeTest.cmake +++ b/Tests/RunCMake/FetchContent/RunCMakeTest.cmake
@@ -15,6 +15,7 @@ run_cmake(MakeAvailable) run_cmake(MakeAvailableTwice) run_cmake(MakeAvailableUndeclared) +run_cmake(VerifyHeaderSet) run_cmake_with_options(ManualSourceDirectory -D "FETCHCONTENT_SOURCE_DIR_WITHPROJECT=${CMAKE_CURRENT_LIST_DIR}/WithProject"
diff --git a/Tests/RunCMake/FetchContent/VerifyHeaderSet-stdout.txt b/Tests/RunCMake/FetchContent/VerifyHeaderSet-stdout.txt new file mode 100644 index 0000000..354529d --- /dev/null +++ b/Tests/RunCMake/FetchContent/VerifyHeaderSet-stdout.txt
@@ -0,0 +1,4 @@ +-- Before subproject, var = 'TRUE' +-- Inside subproject, var = 'FALSE' +-- After subproject, var = 'TRUE' +-- Subproject target property VERIFY_INTERFACE_HEADER_SETS='FALSE'
diff --git a/Tests/RunCMake/FetchContent/VerifyHeaderSet.cmake b/Tests/RunCMake/FetchContent/VerifyHeaderSet.cmake new file mode 100644 index 0000000..8adfcea --- /dev/null +++ b/Tests/RunCMake/FetchContent/VerifyHeaderSet.cmake
@@ -0,0 +1,16 @@ +enable_language(C) + +set(CMAKE_VERIFY_INTERFACE_HEADER_SETS TRUE) + +include(FetchContent) +FetchContent_Declare(verify_subproj + SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/VerifyHeaderSet +) +message(STATUS "Before subproject, var = '${CMAKE_VERIFY_INTERFACE_HEADER_SETS}'") +FetchContent_MakeAvailable(verify_subproj) + +# Provide a way to verify the variable was reset back to its original value +message(STATUS "After subproject, var = '${CMAKE_VERIFY_INTERFACE_HEADER_SETS}'") + +get_property(verify TARGET Blah PROPERTY VERIFY_INTERFACE_HEADER_SETS) +message(STATUS "Subproject target property VERIFY_INTERFACE_HEADER_SETS='${verify}'")
diff --git a/Tests/RunCMake/FetchContent/VerifyHeaderSet/CMakeLists.txt b/Tests/RunCMake/FetchContent/VerifyHeaderSet/CMakeLists.txt new file mode 100644 index 0000000..c6ba37e --- /dev/null +++ b/Tests/RunCMake/FetchContent/VerifyHeaderSet/CMakeLists.txt
@@ -0,0 +1,9 @@ +cmake_minimum_required(VERSION 3.24) +project(VerifyHeaderSet LANGUAGES C) + +message(STATUS "Inside subproject, var = '${CMAKE_VERIFY_INTERFACE_HEADER_SETS}'") + +add_library(Blah INTERFACE) +target_sources(Blah + INTERFACE FILE_SET HEADERS FILES blah.h +)
diff --git a/Tests/RunCMake/FetchContent/VerifyHeaderSet/blah.h b/Tests/RunCMake/FetchContent/VerifyHeaderSet/blah.h new file mode 100644 index 0000000..5b47e14 --- /dev/null +++ b/Tests/RunCMake/FetchContent/VerifyHeaderSet/blah.h
@@ -0,0 +1 @@ +#error Header was used