1763c31 Set policy CMP0025 to NEW while building CMake itself
aa53ee5 Add policy CMP0025 for Apple Clang compiler id compatibility
ab65862 Clang: Add separate "AppleClang" compiler id
The parent commit introduced a separate "AppleClang" compiler id for
Apple's Clang distribution. Add a policy in order to support projects
that expect this compiler's id to be just "Clang". When the policy is
OLD or not set, map AppleClang back to Clang. Continue to use the
AppleClang id internally while enabling the language, but set the
CMAKE_<LANG>_COMPILER_ID after project() or enable_language() to the
compatible value for use by project code.
This target type only contains INTERFACE_* properties, so it can be
used as a structural node. The target-specific commands enforce
that they may only be used with the INTERFACE keyword when used
with INTERFACE_LIBRARY targets. The old-style target properties
matching LINK_INTERFACE_LIBRARIES_<CONFIG> are always ignored for
this target type.
The name of the INTERFACE_LIBRARY must match a validity generator
expression. The validity is similar to that of an ALIAS target,
but with the additional restriction that it may not contain
double colons. Double colons will carry the meaning of IMPORTED
or ALIAS targets in CMake 2.8.13.
An ALIAS target may be created for an INTERFACE library.
At this point it can not be exported and does not appear in the
buildsystem and project files are not created for them. That may
be added as a feature in a later commit.
The generators need some changes to handle the INTERFACE_LIBRARY
targets returned by cmComputeLinkInterface::GetItems. The Ninja
generator does not use that API, so it doesn't require changes
related to that.
Convert the incoming value to a path in the same way that the
already-cached value was converted before comparison.
Do the actual comparison only one time, after both values are
normalized.
* The ALIAS name must match a validity regex.
* Executables and libraries may be aliased.
* An ALIAS acts immutable. It can not be used as the lhs
of target_link_libraries or other commands.
* An ALIAS can be used with add_custom_command, add_custom_target,
and add_test in the same way regular targets can.
* The target of an ALIAS can be retrieved with the ALIASED_TARGET
target property.
* An ALIAS does not appear in the generated buildsystem. It
is kept separate from cmMakefile::Targets for that reason.
* A target may have multiple aliases.
* An ALIAS target may not itself have an alias.
* An IMPORTED target may not have an alias.
* An ALIAS may not be exported or imported.
9cf3547 Add the INTERFACE_SYSTEM_INCLUDE_DIRECTORIES target property.
1925cff Add a SYSTEM parameter to target_include_directories (#14180)
286f227 Extend the cmTargetPropCommandBase interface property handling.
83498d4 Store system include directories in the cmTarget.
f1fcbe3 Add Target API to determine if an include is a system include.
2679a34 Remove unused variable.
Unlike other target properties, this does not have a corresponding
non-INTERFACE variant.
This allows propagation of system attribute on include directories
from link dependents.
d7dd010 Add target property debugging for COMPILE_DEFINITIONS
1841215 Refactor cmTarget::GetCompileDefinitions to use an out-vector, not a string.
afc9243 Add an overload of cmIDEOptions::AddDefines taking a vector of strings.
d95651e Overload cmLocalGenerator::AppendDefines to add a list.
Use constructs similar to those for COMPILE_OPTIONS. This is a little
different because there is a command to remove_definitions(), so
we can't populate the equivalent target property until generate-time
in cmGlobalGenerator.
When CMake reports failure to configure a project, especially when the
toolchain does not initialize properly, the true reason may be clear
from reading the CMakeFiles/CMake(Output|Error).log files. Advise users
to look at these files if they exist when configuration fails.
Add RunCMake.Configure test to check that the log files are mentioned
when configuration fails.
The idea is to write to a temp file which contains generator
expressions, and at generate time, evaluate the generator expressions,
and write the result to a file.
Because executables on Windows are limited in the length of command line
it is possible to use, it is common to write command line arguments to a
file instead and specify the file as a source of arguments.
This new FILE(GENERATE) subcommand allows the use of generator
expressions to create such files so that they can be used with
add_custom_command for example.
Extend the cmGlobalGenerator::GenerateBuildCommand virtual method
signature with a "projectDir" parameter specifying the top of the
project build tree for which the build command will be generated.
Populate it from call sites in cmGlobalGenerator::Build where a
fully-generated build tree should be available.
Commit 79568f95 (automoc: Add source file to target early to set the
linker language, 2013-02-20) changed automoc initialization to a two
step process. In the first step, the generated source file was added
to the target, which allows the link language to be determined.
However, this bypassed the check for the availability of Qt itself.
At build-time the automoc file could not be generated because the moc
tool was not available to create it.
The solution is to only add the automoc file to the target if Qt is
found.
Previously, GetIncludeDirectories was called before calling
target->AddSourceFile(mocCppSource). Since commit a1c4905f (Use the
link information as a source of compile definitions and
includes., 2013-02-12), the include directories are determined by
the link information.
Valid link information requires that the linker language can be
determined, which depends on the source files languages and the
dependent targets languages. In the case of the no_link_languages
target in the unit test, there are no dependencies and the additional
source file no_link_languages_automoc.cpp is added to the target
at generate-time. That file can be used to determine the linker
language, but it must be added to the target before calling
GetIncludeDirectories.
Reject the option by default. It will be implemented on a per-generator
basis. Pass the setting into try_compile project generation. Add cache
entry CMAKE_GENERATOR_TOOLSET and associated variable documentation to
hold the value persistently.
Add a RunCMake.GeneratorToolset test to cover basic "-T" option cases.
Verify that CMAKE_GENERATOR_TOOLSET is empty without -T, that -T is
rejected when the generator doesn't support it, and that two -T options
are always rejected.
6063fef Output include directories as LOG messages, not warnings.
aa66748 Specify the target whose includes are being listed.
d70204a Only output includes once after the start of 'generate-time' when debugging.
0d46e9a Store includes from the same include_directories call together.
During configure-time, GetIncludeDirectories may be called too, for example
if using the export() command. As the content can be different, it should
be output each time then.
This makes
set(CMAKE_BUILD_INTERFACE_INCLUDES ON)
add the equivalent of
set_property(TARGET tgt APPEND PROPERTY
INTERFACE_INCLUDE_DIRECTORIES
$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR};${CMAKE_CURRENT_BINARY_DIR}>
)
to every target.
If the headers are in CMAKE_CURRENT_SOURCE_DIR, and the generated headers
are in CMAKE_CURRENT_BINARY_DIR, this is a convenient way to build a target
bar, which depends on foo, just by using target_link_libraries() and adding
the INTERFACE_INCLUDE_DIRECTORIES to the INCLUDE_DIRECTORIES of the target
being linked. There will be more-convenient porcelain API to consume the
property in the future.
Solution folders are supported as read-only in the VS11 Express
Edition, so do not prohibit their use just because we detect the
express edition (as we did in the VS10 generator).
Inspired-by: Paris
75ebebc VS: Remove platform specific generator files
8b62080 VS: Remove EnableLanguage from platform-specific generators
5bdf011 VS: Remove GetPlatformName from platform-specific generators
8d42ab4 VS: Fix ArchitectureId of Visual Studio 10 IA64 generator
6f439b3 VS: Remove AddPlatformDefinitions from platform-specific generators
5170a88 Make cmGlobalGenerator::GetDocumentation() a static function
04ff866 Allow a GeneratorFactory handling of more than one generator
984ebc3 Search generator in cmake::ExtraGenerators before in cmake::Generators
30a6950 Add cmGlobalGeneratorFactory::GetGenerators()
e8f8414 Introduce the abstract class cmGlobalGeneratorFactory
Since commit ca39c5cd (Optionally allow IMPORTED targets to be globally
visible, 2012-01-25) cmGlobalGenerator has a second member that tracks
targets with global scope. We must initialize the new 'ImportedTargets'
member wherever the old 'TotalTargets' member is initialized. Without
this initialization the ImportedTargets member is left with dangling
pointers during a same-process re-configuration.
We're going to need to link to them, and all the linking API is moving
to cmGeneratorTarget.
Skip imported targets when iterating over cmGeneratorTargets in places
where we only want targets we build. The GetGeneratorTargets result now
includes IMPORTED targets where it didn't before. The GetTargets
result, which was what used to be called in these methods does not
include IMPORTED targets. This doesn't relate to any known bugs, but in
some future uses of GetGeneratorTargets it will be important, so
starting the convention and being deliberate now is a good idea.
This fixes a regression introduced in commit 290e92ad (Move
GetIncludeDirectories to cmGeneratorTarget, 2012-09-16) which loops over
cmGeneratorTargets before they get created, so the container is empty.
4ad0233 Remove period at the end of the check message.
50b1ea5 Fix minor typos.
19c3206 Remove unused parameter marker and the unused parameter.
9d462b2 Document that generator expressions can be used in target properties.
daf88c3 Fix punctuation in some variables documentation.
3172cde Fix the layout of the generator expression documentation.
This way we don't need to check the definitions from the Makefile when
generating later, and can more easily add generator expressions.
Duplication is not a problem as the definitions are de-duplicated before
generating.
At the top of a build tree we configure inside the CMakeFiles directory
files such as "CMakeSystem.cmake" and "CMake<lang>Compiler.cmake" to
save information detected about the system and compilers in use. The
method of detection and the exact results store varies across CMake
versions as things improve. This leads to problems when loading files
configured by a different version of CMake. Previously we ignored such
existing files only if the major.minor part of the CMake version
component changed, and depended on the CMakeCache.txt to tell us the
last version of CMake that wrote the files. This led to problems if the
user deletes the CMakeCache.txt or we add required information to the
files in a patch-level release of CMake (still a "feature point" release
by modern CMake versioning convention).
Ensure that we always have version-consistent platform information files
by storing them in a subdirectory named with the CMake version. Every
version of CMake will do its own system and compiler identification
checks even when a build tree has already been configured by another
version of CMake. Stored results will not clobber those from other
versions of CMake which may be run again on the same tree in the future.
Loaded results will match what the system and language modules expect.
Rename the undocumented variable CMAKE_PLATFORM_ROOT_BIN to
CMAKE_PLATFORM_INFO_DIR to clarify its purpose. The new variable points
at the version-specific directory while the old variable did not.
When a language is not enabled at the top level of a project but is
enabled in multiple disjoint subdirectories we should re-use the
CMake<lang>Compiler.cmake file from the first directory. Load the file
whenever it exists and is not left from a different version of CMake.
bd34963 Refactor generation of shared library flags
55d7aa4 Add platform variable for flags specific to shared libraries
31d7a0f Add platform variables for position independent code flags
CMAKE_SHARED_LIBRARY_<lang>_FLAGS has flags on various platforms for a
variety of purposes that are correlated with shared libraries but not
exclusive to them. Refactor generation of these flags to use new
purpose-specific platform variables
CMAKE_<lang>_COMPILE_OPTIONS_DLL
CMAKE_<lang>_COMPILE_OPTIONS_PIC
CMAKE_<lang>_COMPILE_OPTIONS_PIE
Activate the DLL flags specifically for shared libraries. Add a new
POSITION_INDEPENDENT_CODE target property to activate PIC/PIE flags, and
default to true for shared libraries to preserve default behavior.
Initialize the new property from CMAKE_POSITION_INDEPENDENT_CODE to
allow easy global configuration in projects.
Although the default behavior is unchanged by this refactoring, the new
approach ignores CMAKE_SHARED_LIBRARY_<lang>_FLAGS completely. We must
leave it set in case projects reference the value. Furthermore, if a
project modifies CMAKE_SHARED_LIBRARY_<lang>_FLAGS it expects the new
value to be used. Add policy CMP0018 to handle compatibility with
projects that modify this platform variable.
Add a PositionIndependentCode test on platforms where we can get
meaningful results.
Add cmGlobalGenerator::GenerateRuleFile to compute a generator-specific
rule file location. This will allow specific generators to override the
location of .rule files without changing the behavior of other
generators.
Rename cmGlobalGenerator::GetCMakeCFG{InitDirectory => IntDir} to
have a shorter name without a typo. Add a 'const' qualifier since
the method is only for lookup and never needs to modify anything.
Add a virtual cmGlobalGenerator::ComputeTargetObjects method invoked
during cmGeneratorTarget construction. Implement it in the Makefile
generator to pre-compute all object file names for each target. Use
the results during generation instead of re-computing it later.
Construct the instances after the final set of targets is known but
before computing inter-target dependencies. This order will allow
initialization of cmGeneratorTarget instances to adjust and finalize
declared inter-target dependencies.
Eliminate callers of cmMakefile::GetIncludeDirectories.
All callers of GetIncludeDirectories should go through the local generator
object.
Only the local generator calls cmTarget::GetIncludeDirectories directly.
Consider the case motivating commit e01cce28 (Allow add_dependencies()
on imported targets, 2010-11-19). An imported target references a file
generated at build time by a custom target on which it depends. Had the
file been built directly using add_library or add_executable its target
name would have been visible globally. Therefore the imported target
representing the file should be globally visible also.
Teach the IMPORTED signature of add_(executable|library) to accept a new
"GLOBAL" option to make the imported target visible globally.
59238dc Fix --find-package mode on Cygwin, where enable_language(RC) is called
98472e4 Require the current cmake version in --find-package mode
a6ccf3c Use $(CXXFLAGS) and $(LDFLAGS) in the --find-package test Makefile
4386918 Fix line length
7d69310 Only enable the test when using GNU make
3011149 Make the test harder by always having a space in the include dirs
ab57ff6 Make the --find-package test harder
626fc71 Much improved test, should now be executed on all UNIXes
ec6982d Disable any STATUS output in --find-package mode
e552ae7 Dont check for -isysroot and -mmacosx-version on OSX in --find-package mode
e589589 Rename helper macros print_compile_flags() to set_compile_flags_var()
aecfc1f Fix test on OpenBSD with BSD make
6bb4ca3 The makefile for the test was kindof wrong
fd15b5e Only run the test if we are using a makefile generator under UNIX
9fc87c6 Add a test for the new --find-package mode
d3ae0ff Improve documentation for --find-package mode
bf07375 Add a cmake.m4 for using cmake in autoconf projects instead of pkgconfig
b0e3578 Use the file-utility to test for 64bit if there is no /usr/lib64
53edfb2 Better support for lib64 and Debian multiarch
b8fdaa1 Fix copyright notice in new CMakeFindPackageMode.cmake
7690edf Replace cmake::GetScriptMode() with GetWorkingMode()
e4f603b Implement find-package mode of cmake
a91d662 Add find-package mode, which does nothing yet
b976e70 Make clLocalGenerator::GetTargetFlags() public
dd2f814 Merge branch 'dev/add_test-working-directory' into dev/strict-mode
949d32c Unwatch manual variables upon removal in cmake-gui
3939032 Unwatch manual variables upon removal in ccmake
8354413 Add method to unwatch a manual variable
8ed3c85 Give a better message for unused variables
729db48 Fix ArgumentExpansion test expected results
89c2544 Checking for a definition is a usage
5625dee Don't output to stderr in the GUI
ad25a96 Merge branch 'ImprovedDotSupport2' into dev/strict-mode
c128abe Merge branch 'AddCMAKE_CURRENT_LIST_DIR' into dev/strict-mode
9bcaff0 Merge branch 'cmake-guiRememberAdvancedCheckbox' into dev/strict-mode
544d0c3 Fix expected output for WarnUninitialized test
4e3bea4 Update expected messages to new format
8e8c9e4 Don't check at destruction for usage
668e005 Use cmake::IssueMessage for warnings
88cd4c1 Use 'CMake Warning' versus 'warning' for CDash
3c3b98d Initialize the class before setting warn flags
cf8b15a Ignore files under the CMakeFiles directory
fd50f06 Don't check for unused vars at configure time
447a04c Don't warn during configure when doing everything
b97ee21 Check for unused variables at the end of generate
c18c977 When checking for variables, specify a reason
3f1121f Use a long int since Line is a long as well
2507f93 Change the failure case string to 'Unexpected'
fe390a2 Add 'ArgumentExpansion' test
8dbb209 Wrong boolean value for CLI warnings
d4ee998 Hard-code the --no-warn-unused-cli flag
a267b99 Fix line lengths
82ed104 Flag that the directories have been set
5aa535b Add argument to arg parsing to not set directories
367e5c3 Revert "Revert "When calling CMake, set the args and the cache""
ab5d4e4 Revert "When calling CMake, set the args and the cache"
9b90040 When calling CMake, set the args and the cache
fe56002 Fix long lines for KWStyle
5d30cfc Set a watch on variables added through the gui
33c63b1 Add a method to put a watch for variables
535253f Initialize the warning variables earlier
cbb286c Fix the path detection to work for top-level
62be1f7 Initialize the usage stack earlier
c6e7fab Factor out the checks for unused variables
5e41ba8 When using the API, check for Add vs. Remove
dee1976 Fix typo in VariableUnusedViaUnset test
f231ce5 Remove old false positive avoidance code
a117e02 Revert "Add test for unused warnings at the end of scope"
2c82f2b Exempt CMAKE(CURRENT|PARENT)_LIST_FILE from usage
6d7d449 Ignore CLI warnings for ABI determination
7740a73 Only return local keys that are defined
bef3aee Use the API so that warnings can be tracked
05cb0f4 Check for unused variables in the dtor
91c4c99 Add test for unused warnings at the end of scope
ca90f67 Fix detection of unused variables when setting
f7438ca Add test for unused detection via setting it
995cfb0 Don't warn if the variable wasn't defined
aefc91d Add test for usage checks via unset
a8e97f8 Remove VarRemoved code since it's been superceded
59463ef Rework CheckVariableForUnused usage
f117423 Fix line lengths to be no more than 78
e49a935 Improve unused warning logic
e01e40c Mark ARGC, ARGV*, and ARGN as used
a17aff7 Ignore CMAKE_MATCH_* variables for usage
02a114d Add method to allow variables to be marked as used
a0b0d23 CMAKE_DO_TRY_COMPILE is no longer used
ae3eff3 Fix the path used for ignoring system warnings
056b441 Fix missing case for usage of a variable
980e048 Factor out checks for unused variables
83acb0a Remove now unused variables
3801463 Use built-ins for readability and maintainability
8b52015 Push the initialize and unused states when copying
439877f Be consistent with single and double quotes
4cf1706 Add documentation for check-system-vars
b74777f Fix the spelling of the flag for warn-unused-vars
b948120 Change logic of flag to turn off cli unused checks
f047a17 Add test for uninitialized variables
75bda38 Add tests for unused command line variables
300fc15 Fix detection of system files
d784e6a Run the unused variables check on the final pass
9efc057 VariableWatch is not available when bootstrapping
2e78224 Add a missing comma to the warning message
7499700 Add a flag to warn about system files
fff9f6d Rename flags again and use variablewatch for cli
786e269 Add warn-unused to the Qt interface
636e6c4 Default to marking things as used
4ff0340 Rename find-unused to warn-unused
d7999e9 Rename strict-mode to warn-uninitialized
e141bc9 Detect unused variables
d3e8eb5 Add flags to detect unused variables
f332e14 Complete strict-mode checks for uninitialized vars
52f9637 Add method to get the local scope variables
f794d58 Make --strict-mode option, and integrate with cmake-gui
48b5b85 Add a warning when variables are used uninitialized.
cd626ea For macros make sure the FilePath points to a valid pointer in the args.
During a try_compile cmGlobalGenerator::EnableLanguage uses results from
the outer project. Reject attempts to enable languages in the test
project that are not "ready" in the outer project. Mark a language as
"ready" when all its information has been loaded and we are ready to
generate build rules.
This also avoids infinite recursion introduced by commit 295b5b60 (Honor
CMAKE_USER_MAKE_RULES_OVERRIDE in try_compile, 2010-06-29) for projects
that set CMAKE_USER_MAKE_RULES_OVERRIDE to a file that uses try_compile.
The file is loaded along with the information for a given langauge so
the language is not yet "ready".
4499d50 Mark CustomCommand test perconfig.out as SYMBOLIC
f0cdb60 Introduce "generator expression" syntax to custom commands (#11209)
4749e4c Record set of targets used in cmGeneratorExpression
ef9e9de Optionally suppress errors in cmGeneratorExpression
45e1953 Factor per-config sample targets out of 'Testing' test
4091bca Factor generator expression docs out of add_test
bfb7288 Record backtrace in cmCustomCommand
Remove a boolean parameter of cmGlobalGenerator::CreateGlobalTarget that
is never set to true anymore. Remove global target "consolidation" loop
because no global targets exist before it runs anymore.
Visual Studio Express editions do not support solution folders,
so default behavior should be as if USE_FOLDERS global property
is OFF.
Also, allow folder names to be the same as target names: internally,
use a prefix to distinguish folder GUIDs from target GUIDs. Add
a target and folder with the same name in the ExternalProject
test to exercise this code.
For CMake itself, provide a new option CMAKE_USE_FOLDERS that
defaults to ON so that Visual Studio users get a nicely organized
CMake project. Express edition users will have to turn off the
CMAKE_USE_FOLDERS option in order to build CMake in the VS Express
IDE.
Since commit bc43b0f2 (Do not link library dependencies in VS solutions,
2009-10-20) CMake disables for VS >= 8 linking of a target to libraries
that happen to be listed as solution-level dependencies. Therefore we
can list the direct dependencies of each target in the solution file and
let VS handle transitive dependencies automatically.
This work was started from a patch by Thomas Schiffer.
Thanks, Thomas!
See the newly added documentation of the FOLDER target
property for details.
Also added global properties, USE_FOLDERS and
PREDEFINED_TARGETS_FOLDER. See new docs here, too.
By default, the FOLDER target property is used to organize
targets into folders in IDEs that have support for such
organization.
This commit adds "solution folder" support to the Visual
Studio generators. Currently works with versions 7 through
10.
Also, use the new FOLDER property in the ExternalProject
test and in the CMake project itself.
a99f620 Fix unused parameter warning in VS 7.1 generator
79a88c3 Refactor VS <= 7.1 utility-depends workaround
325bdb2 Factor out duplicate VS target dependency code
6bea843 Factor out global generator ComputeTargetDepends method
We store custom command rule hashes in CMakeFiles/CMakeRuleHashes.txt
persistently across CMake runs. When the rule hash changes we delete
the custom command output file and write a new hash into the persistence
file.
This functionality was first added by the commit 'Introduce "rule
hashes" to help rebuild files when rules change.' (2008-06-02).
However, the implementation in cmGlobalGenerator::CheckRuleHashes kept
the file open for read when attempting to rewrite a new file. On
Windows filesystems this prevented the new version of the file from
being written! This caused the first set of rule hashes to be used
forever within a build tree, meaning that all custom commands whose
rules changed would be rebuilt every time CMake regenerated the build
tree.
In this commit we address the problem by splitting the read and write
operations into separate methods. This ensures that the input stream is
closed before the output stream opens the file.
CMake has a special case for the "make install" target when building
CMake itself. We use the just-built CMake to install itself since an
existing CMake installation cannot replace itself (at least on Windows).
We simplify the code that computes the location of the CMake binary by
taking advantage of existing generator support for target lookup. This
will make it robust to any changes in CMake's own CMakeLists.txt files
in the future.
In cmGlobalGenerator::GetTargetSets we collect targets from all local
generators in a tree or subtree corresponding to a project() command.
Some targets, such as ALL_BUILD, are duplicated in each subdirectory
with a project() command. For such targets we should keep only the copy
for the top-most (root) local generator.
Previously this filtering was done in each VS IDE generator, but it is
easier to do it in one place when the targets are first encountered.
This also fixes bad ALL_BUILD dependencies generated for VS 7.0 because
the cmGlobalVisualStudio7Generator::WriteTargetDepends method was not
filtering out duplicates. Now we avoid duplicates from the start.
This commit cleans up the declaration, definition, and invocations of
the GetTargetSets method and related code. There is no change in
function except to make the method virtual.
This converts the CMake license to a pure 3-clause OSI-approved BSD
License. We drop the previous license clause requiring modified
versions to be plainly marked. We also update the CMake copyright to
cover the full development time range.
The cmGlobalGenerator::AddTargetDepends method traces the dependencies
of targets recursively to collect the complete set of targets needed for
a given project (for VS .sln files). This commit teaches the method to
avoid tracing its dependencies more than once. Otherwise the code does
an all-paths walk needlessly.
The try_compile command builds the cmTryCompileExec executable using the
cmTryCompileExec/fast target with Makefile generators in order to save
time since dependencies are not needed. However, in project mode the
command builds an entire source tree that may have dependencies.
Therefore we can use the /fast target approach only in one-source mode.
When building an entire source tree with try_compile instead of just a
single source file, it is possible that the CMakeLists.txt file in the
try-compiled project invokes try_compile. This commit fixes propagation
of language-initialization results from the outer-most project into any
number of try-compile levels.
This generalizes the previous CMakeFiles/LabelFiles.txt created at the
top of the build tree to a CMakeFiles/TargetDirectories.txt file. It
lists the target support directories for all targets in the project.
Labels can still be loaded by looking for Labels.txt files in each
target directory.
The second argument of add_subdirectory must name a unique binary
directory or the build files will clobber each other. This enforces
uniqueness with an error message.
Brad King
Stephen Kelly
Andreas Mohr
Petr Kmoch
Peter Kümmel
Yury G. Kudryashov
David Cole
Patrick Gansterer
Alex Neundorf
Peter Collingbourne
Johan Björk
Ben Boeckel
Bill Hoffman