CMake: Handle empty INCLUDE_DIRECTORIES in genex for qdoc

Follow the pattern recommended in the CMake docs for the $<JOIN:...>
generator expression. Wrap it in a $<BOOL:...> genex so that if a
target's INCLUDE_DIRECTORIES property is empty, we don't add a
stray -I with no directory following it. This fixes the following error
when running qdoc:

  qdoc: Missing value after '-I'.

Task-number: QTBUG-88838
Change-Id: Ie3ef2625fbb29cc501f7fc22ff7a9cc8ac548322
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
(cherry picked from commit bac73a36e25076a5929c7feac0675860772e7270)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
This commit is contained in:
Craig Scott 2020-11-27 12:41:21 +11:00 committed by Qt Cherry-pick Bot
parent 862b967449
commit 1f443c36f2

View File

@ -65,7 +65,7 @@ function(qt_internal_add_docs)
if (NOT target_type STREQUAL "UTILITY")
file(GENERATE
OUTPUT ${target_include_dirs_file}
CONTENT "-I$<JOIN:${include_paths_property},\n-I>"
CONTENT "$<$<BOOL:${include_paths_property}>:-I$<JOIN:${include_paths_property},\n-I>>"
)
set(include_path_args "@${target_include_dirs_file}")
else()