From 9abd63dd3aea53008d1d01dc361a1a486215520c Mon Sep 17 00:00:00 2001
From: Arcturus Arcturus <arcturus98@outlook.com>
Date: Fri, 29 Oct 2021 23:02:34 +0100
Subject: Help: Explain how target SOURCES are interpreted
Co-Authored-By: Craig Scott <craig.scott@crascit.com>
---
Help/prop_tgt/SOURCES.rst | 36 ++++++++++++++++++++++++++++++++++--
1 file changed, 34 insertions(+), 2 deletions(-)
diff --git a/Help/prop_tgt/SOURCES.rst b/Help/prop_tgt/SOURCES.rst
index 493643e..1ebfa14 100644
--- a/Help/prop_tgt/SOURCES.rst
+++ b/Help/prop_tgt/SOURCES.rst
@@ -1,6 +1,38 @@
SOURCES
-------
-Source names specified for a target.
+This specifies the list of paths to source files for the target.
+The following commands all set or add to the ``SOURCES`` target property
+and are the usual way to manipulate it:
-List of sources specified for a target.
+* :command:`add_executable`
+* :command:`add_library`
+* :command:`add_custom_target`
+* :command:`target_sources`
+
+Contents of ``SOURCES`` may use
+:manual:`generator expressions <cmake-generator-expressions(7)>`.
+If a path starts with a generator expression, it is expected to
+evaluate to an absolute path. Not doing so is considered undefined behavior.
+
+Paths that are for files generated by the build will be treated
+as relative to the build directory of the target, if the path is not
+already specified as an absolute path. Note that whether a file is seen as
+generated may be affected by policy :policy:`CMP0118`.
+
+If a path does not start with a generator expression, is not an
+absolute path and is not a generated file, it will be treated as relative to
+the location selected by the first of the following that matches:
+
+* If a file by the specified path exists relative to the target's source
+ directory, use that file.
+* If policy :policy:`CMP0115` is not set to ``NEW``, try appending each
+ known source file extension to the path and check if that exists
+ relative to the target's source directory.
+* Repeat the above two steps, this time relative to the target's binary
+ directory instead.
+
+Note that the above decisions are made at generation time, not build time.
+
+See the :manual:`cmake-buildsystem(7)` manual for more on defining
+buildsystem properties.
--
cgit v0.12
From 9fac18a4a666b0c6b6b66a05ac2aa0c515a4681a Mon Sep 17 00:00:00 2001
From: Arcturus Arcturus <arcturus98@outlook.com>
Date: Thu, 28 Oct 2021 22:05:26 +1100
Subject: Help: Clarify target_sources path conversion w.r.t generator
expressions
With some of the content expanded, reorder a few paragraphs
and tweak some of the wording to improve the flow.
Co-Authored-By: Craig Scott <craig.scott@crascit.com>
---
Help/command/target_sources.rst | 49 ++++++++++++++++++++++++++---------------
1 file changed, 31 insertions(+), 18 deletions(-)
diff --git a/Help/command/target_sources.rst b/Help/command/target_sources.rst
index 2fded5e..2039da5 100644
--- a/Help/command/target_sources.rst
+++ b/Help/command/target_sources.rst
@@ -15,37 +15,50 @@ Specifies sources to use when building a target and/or its dependents.
The named ``<target>`` must have been created by a command such as
:command:`add_executable` or :command:`add_library` or
:command:`add_custom_target` and must not be an
-:ref:`ALIAS target <Alias Targets>`.
-
-.. versionchanged:: 3.13
- Relative source file paths are interpreted as being relative to the current
- source directory (i.e. :variable:`CMAKE_CURRENT_SOURCE_DIR`).
- See policy :policy:`CMP0076`.
+:ref:`ALIAS target <Alias Targets>`. The ``<items>`` may use
+:manual:`generator expressions <cmake-generator-expressions(7)>`.
.. versionadded:: 3.20
``<target>`` can be a custom target.
The ``INTERFACE``, ``PUBLIC`` and ``PRIVATE`` keywords are required to
-specify the scope of the items following them. ``PRIVATE`` and ``PUBLIC``
-items will populate the :prop_tgt:`SOURCES` property of
-``<target>``, which are used when building the target itself.
+specify the scope of the source file paths (``<items>``) that follow
+them. ``PRIVATE`` and ``PUBLIC`` items will populate the :prop_tgt:`SOURCES`
+property of ``<target>``, which are used when building the target itself.
``PUBLIC`` and ``INTERFACE`` items will populate the
:prop_tgt:`INTERFACE_SOURCES` property of ``<target>``, which are used
-when building dependents.
-The following arguments specify sources. Repeated calls for the same
-``<target>`` append items in the order called. The targets created by
-:command:`add_custom_target` can only have ``PRIVATE`` scope.
+when building dependents. A target created by :command:`add_custom_target`
+can only have ``PRIVATE`` scope.
+
+Repeated calls for the same ``<target>`` append items in the order called.
.. versionadded:: 3.3
Allow exporting targets with :prop_tgt:`INTERFACE_SOURCES`.
.. versionadded:: 3.11
- Allow setting ``INTERFACE`` items on :ref:`IMPORTED targets <Imported Targets>`.
+ Allow setting ``INTERFACE`` items on
+ :ref:`IMPORTED targets <Imported Targets>`.
+
+.. versionchanged:: 3.13
+ Relative source file paths are interpreted as being relative to the current
+ source directory (i.e. :variable:`CMAKE_CURRENT_SOURCE_DIR`).
+ See policy :policy:`CMP0076`.
+
+A path that begins with a generator expression is left unmodified.
+When a target's :prop_tgt:`SOURCE_DIR` property differs from
+:variable:`CMAKE_CURRENT_SOURCE_DIR`, use absolute paths in generator
+expressions to ensure the sources are correctly assigned to the target.
+
+.. code-block:: cmake
+
+ # WRONG: starts with generator expression, but relative path used
+ target_sources(MyTarget "$<$<CONFIG:Debug>:dbgsrc.cpp>")
+
+ # CORRECT: absolute path used inside the generator expression
+ target_sources(MyTarget "$<$<CONFIG:Debug>:${CMAKE_CURRENT_SOURCE_DIR}/dbgsrc.cpp>")
-Arguments to ``target_sources`` may use "generator expressions"
-with the syntax ``$<...>``. See the :manual:`cmake-generator-expressions(7)`
-manual for available expressions. See the :manual:`cmake-buildsystem(7)`
-manual for more on defining buildsystem properties.
+See the :manual:`cmake-buildsystem(7)` manual for more on defining
+buildsystem properties.
.. code-block:: cmake
--
cgit v0.12