In commit cb14ae2b87 (try_compile: Add SOURCE_FROM_{ARG,VAR},
2022-09-21, v3.25.0-rc1~94^2~2) we accidentally added unbalanced closing
`]` characters in the `try_compile` and `try_run` signatures.
Fixes: #24053
Change the SOURCE_FROM_ARG keyword to try_compile to SOURCE_FROM_CONTENT
(which we can do because it was recently added and hasn't been in a
release yet). The new name should be clearer as to what it does, and
also more consistent with the CONTENT arguments to some other commands.
Also, fix a typo in an error message.
Add ability to copy try_compile (and try_run) source files from
arbitrary locations into the operation directory. This is included for
the sake of completion and consolidation, although use cases which
actually require this may be rare.
Add ability to "feed" try_compile (and try_run) sources more directly,
either from literal content, or from a CMake variable which contains
literal content. This saves the user from needing a separate step to
write the content to a file, and allows for the sources to only exist in
the scratch directory.
Introduce a new signature for try_compile (and try_run) which removes
the `bindir` argument and requires the SOURCES tag. This will eventually
allow us to add other ways of providing sources, but also allows us to
change the behavior without breaking compatibility.
The old signature uses a special, but non-unique temporary location
inside the specified `bindir`, which conventionally is just the
project's build directory. The new signature unconditionally uses the a
unique temporary directory which is unconditionally within the project's
build directory (which is no longer separately specified). This ensures
that successive runs do not overwrite previous runs, will simplify
debugging, and should also, eventually, allow us to execute multiple
trials in parallel.
In commit c705279bae (Help: Add `.. versionadded` directives to commands
documentation, 2020-11-08, v3.20.0-rc1~508^2) we accidentally added
``versionadded`` markup suggesting that the first argument to
`try_compile` was fixed as `RESULT_VAR` prior to CMake 3.14. This was
probably due to misinterpreting the change from commit 7975edeac5 (Help:
User-provided variable names for try_* commands, 2019-02-24,
v3.14.0-rc3~16^2~3).
The result variable has never been fixed. Drop the incorrect markup.
This change ony concerns directives that appear in the document body.
The guidelines for inserting version directives:
* Baseline version is CMake 3.0, i.e. directives start at 3.1.
* Always use `.. versionadded::` directive, avoid ad-hoc version
references. Exception: policy pages.
* For new command signatures, put `versionadded` on a separate line
after the signature.
* For a group of new signatures in a new document section,
a single version note at the beginning of the section is sufficient.
* For new options, put `versionadded` on a separate line before
option description.
* If all the option descriptions in the list are short one-liners,
it's fine to put `versionadded` on the same line as the description.
* If multiple option descriptions in close proximity would have
the same ..versionadded directive, consider adding a single
directive after the list, mentioning all added options.
* For compact value lists and sub-option lists, put a single
`versionadded` directive after the list mentioning all additions.
* When a change is described in a single paragraph, put
`versionadded` into that paragraph.
* When only part of the paragraph has changed, separate the changed
part if it doesn't break the flow. Otherwise, write a follow-up
clarification paragraph and apply version directive to that.
* When multiple version directives are close by, order earlier
additions before later additions.
* Indent related lists and code blocks to include them in the scope
of `versionadded` directive.
Issue: #19715
All uppercase is typically used for command keywords. Non-keyword
arguments should generally be shown as `<something>` according
to the CMake documentation guide.
If the CMAKE_CROSSCOMPILING_EMULATOR variable is defined, and
CMAKE_CROSSCOMPILING is TRUE, then use CMAKE_CROSSCOMPILING_EMULATOR to run
the try_run executables. This prevents the need to populate
TryRunResults.cmake when cross compiling.
Most functionality is already implemented in Source/cmCoreTryCompile.{h,cxx}.
Document and improve argument parsing.
This functionality is already being used by a number of modules, like
CheckCSourceCompiles.cmake, but it is not documented.
