In the current default update step for Git under the ExternalProject_Add
command, a 'git fetch' is always performed, followed by a 'git checkout' and
'git submodule update --recursive'. However, a 'git fetch' can be time
consuming and requires a network connection.
To save time, we look at the current checked out hash, and only perform the
fetch if required. This is performed in a CMake script so we can handle
the conditional logic in a cross platform manner.
0496782 FindBoost: Rewrite documentation
4d92f6c FindBoost: Refactor Boost_FOUND computation and version check
0100f88 FindBoost: Construct a clean Boost_LIBRARIES value
5b9149e FindBoost: Overhaul caching and search repeat behavior
5ec8a69 FindBoost: Use PATH_SUFFIXES to look in "Program Files"
d3260a4 FindBoost: Mark Boost_DIR cache entry as advanced
531612d FindBoost: Remove extra indentation level
-make "find_package(Qt 3)" work
-if DESIRED_QT_VERSION was set, but only the other Qt major version was found
don't override the DESIRED_QT_VERSION set by the user
Some frameworks might be built with the library right at the root
of the framework rather than down in a versioned sub-folder with
a symlink at the root.
Make one of the slashes in the REGEX optional so BundleUtilities
can still properly work with such frameworks ... even if they are
weird. ;-)
Thanks to Tobias Hieta for the bug report and for trying out the fix
before I pushed this commit.
Eclipse may get confused by these linked resources, because it sees
the same source file multiple times then and doesn't recognize
that it's the same file actually.
Alex
When building a project relying on External projects, the launchers were
not used in subprojects built without testing enabled. This was preventing
errors and warnings associated with these subprojects from being
reported on the dashboard.
This commit allows enabling the launchers independently of the value of
"BUILD_TESTING" using one of these two approaches:
1) By setting both CTEST_USE_LAUNCHERS and the env variable
"CTEST_USE_LAUNCHERS_DEFAULT" to 1 in the ctest dashboard driver scripts.
2) By enabling the variable CTEST_USE_LAUNCHERS in the ctest dashboard
driver script and also by ensuring every external project passes the option
-DCMAKE_PROJECT_<projectname>_INCLUDE:FILEPATH=${CMAKE_ROOT}/Modules/CTestUseLaunchers.cmake
Teach FortranCInterface_VERIFY to build the test project in a specific
configuration and pass all flags for that configuration. This ensures
that any modifications made by the user or project to the flag are used in
the test project consistently.
Remove ancient checks left from commit f5d95fb0 (Complete rework of
makefile generators expect trouble, 2002-11-08). Modern FreeBSD and
NetBSD platforms support shared libraries. When cross-compiling the
/usr/include/dlfcn.h may not exist on the host but the toolchain still
supports shared libraries.
The changes in "use PATH_SUFFIXES to simplify find_* calls" on 8/14
regressed important functionality in FindGTK for using find_path to
locate header files in <prefix>/lib/<gtk_package>/include.
The find_path function doesn't search <prefix>/lib only <prefix>/include.
1e47ccb Ninja: add option to enforce usage of response files
e31df03 Ninja: move <OBJECTS> in front of the first linker option
8d674e7 Ninja: move -LIBPATH behind -link option
In the response file also linker options could be passed,
and because <OBJECTS> is replaced by a response file, it
is necessary that no compiler option follows <OBJECTS>.
This reverts commit 5598d9b2a0.
Since commit f1670ab1 (Ninja: don't confuse ninja's rsp files with
nmake's, 2012-09-26) Ninja generator response files are placed in
CMakeFiles/ so the previously existing check already avoids expanding
them.
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.
80112da Merge topic 'AutomocUseTargetProperties' into export-sets
955b966 exports: add a test for exporting dependent targets
6f50a04 exports: define a CMAKE_FIND_PACKAGE_NAME var set by find_package()
0cfd055 exports: move the handling of missing targets into subclasses
190f2c8 exports: fix build with MSVC6
8b5f448 exports: first try at error handling if a target is missing
87f4c01 exports: accept a missing target if it is exported exactly once
999061a exports: store pointers to all installations of each export set
64b3a6c exports: cmGlobalGenerator::ExportSets destructor will clear it
81cdab5 exports: Hold an ExportSet pointer in cm*Export*Generator
5c898fb exports: Add cmExportSetMap class
d13ec1a exports: Create class cmExportSet
4e2347c exports: Rename cmGlobalGenerator::AddTargetToExport{s,}
e846e70 exports: Remove cmTargetExport constructor
81c66c8 exports: Move cmTargetExport to a dedicated header file
ae4ab62 find_package: add support for a <package>_NOT_FOUND_MESSAGE variable
...
If a config-file sets <package>_FOUND to FALSE, it can now give a reason
using the variable <package>_NOT_FOUND_MESSAGE, which is used by cmFindPackage
and FPHSA.
Alex
Write new documentation for this module. Ensure that it formats
correctly in "cmake --help-module FindBoost" output. Show the basic
form of calling find_package(Boost). Document all result variables,
input variables, and cache variables appropriately grouped together.
Explain the search process and how it re-runs when changes are made.
Explain the difference between finding headers/libraries versus finding
a "Boost CMake" package configuraiton file.
Drop the emphasis on Boost_ADDITIONAL_VERSIONS because the
implementation should predict most future versions instead.
Construct an initial Boost_FOUND value immediately after searching for
Boost_INCLUDE_DIR. Base the result only on whether header files for the
requested version were found. Then after searching for component
libraries update Boost_FOUND based on whether all requested components
were found.
Construct the value from scratch based on the component library list.
Avoid accumulating values from repeated find_package(Boost) calls.
If Boost is not found, Boost_LIBRARIES should be empty.
Overhaul the implementation as follows:
(1) Do not cache result variables such as Boost_VERSION,
Boost_LIB_VERSION, Boost_LIBRARY_DIRS, Boost_${COMPONENT}_FOUND,
Boost_${COMPONENT}_LIBRARY, or Boost_LIB_DIAGNOSTIC_DEFINITIONS that are
derived uniquely from other search results. The user should not edit
them anyway.
(2) Add cache value Boost_LIBRARY_DIR to hold the single directory
expected to contain all libraries. Once one library is found, search
only that directory for other libraries.
(3) Use the find_library NAMES_PER_DIR option to consider all possible
library names at the same time.
(4) Collect all documented input and cache variables and detect when
they have been changed by the user. Discard prior search results that
may have been influenced by the changes and search for them again.
Environment variables are not expected to be persistent so use them only
as hints and do not consider changes to them to be meaningful.
The CMake find_path command looks under the proper "Program Files"
directories on Windows with any of the provided PATH_SUFFIXES. This is
simpler and more robust than directly reading ENV{ProgramFiles}. Once
Boost_INCLUDE_DIR has been located we already look next to it for the lib
directory anyway, so we do not need special help to find Boost libraries
under "Program Files".
Since FPHSA is called for multiple compiler languages with "MPI_${lang}"
rather than just "MPI", make sure variables for controlling QUIET,
REQUIRED and VERSION are propagated with names prefixed by MPI_${lang}
as well, rather than just MPI.
The find_package call sets up the values of MPI_FIND_REQUIRED and friends,
but these calls to FPHSA need MPI_${lang}_FIND_REQUIRED and friends in
order to function as intended.
e83cc94 Use the cmGeneratorTarget for the include directories API.
9d8e59d Merge branch 'use-generator-target' into AutomocUseTargetProperties
ea12871 Automoc: also the makefile-COMPILE_DEFINITIONS
894e91a Automoc: do not use DEFINITIONS, but only COMPILE_DEFINITIONS
825d1ab Automoc: fix#13493, use target properties for include dirs
df92864 OS X: Ignore MACOSX_DEPLOYMENT_TARGET during Xcode compiler id
e7e613e OS X: Teach deployment target sanity check about SDK names
43b7479 OS X: Further improve default CMAKE_OSX_SYSROOT selection
2690738 OS X: If CMAKE_OSX_SYSROOT is already set do not compute default
7995722 OS X: Simplify selection of CMAKE_OSX_ARCHITECTURES
1786b12 OS X: Allow CMAKE_OSX_SYSROOT to be a logical SDK name
242f673 Tests/Assembler: Use CMAKE_OSX_SYSROOT to generate .s file
a1c032b bootstrap: Suppress CMAKE_OSX_SYSROOT if CFLAGS have -isysroot
230ea21 OS X: Improve default CMAKE_OSX_SYSROOT selection
a0a0877 OS X: Always generate -isysroot if any SDK is in use
33a60e6 Xcode: Remove unused code reading CMAKE_OSX_SYSROOT_DEFAULT
68c6b13 FindSDL: Stay compatible with old input variables
9ed24c5 FindSDL: Remove from find_... calls PATHS that are set by default
38a0f71 FindSDL: Add my copyright tag to all FindSDL_* modules
020d213 FindSDL: Add version support
61a566c FindSDL: Format documentation
22154c7 FindSDL: Update documentation
4541c07 FindSDL: Add version support for FindSDL_ttf
a28c247 FindSDL: Use SDL_TTF prefix for variables
9f5dbf4 FindSDL: Update documentation
d83f80d FindSDL: Add version support for FindSDL_mixer
c10b691 FindSDL: Use SDL_MIXER prefix for variables
03dd6cc FindSDL: Pass SDL_SOUND_LIBRARY to FIND_PACKAGE_HANDLE_STANDARD_ARGS
326beca FindSDL: Use same capitalization for FPHSA as file name
cfe5b87 FindSDL: Version support for FindSDL_sound
776d3fe FindSDL: Format the documentation
a5194e2 FindSDL: Add "cmake_minimum_required" to "try_compile" project
...
This makes FindPackageHandleStandardArgs and FeatureSummary work correctly.
Keep old variables for compatibility.
Furthermore, format the documentation.
Since commit 1786b121 (OS X: Allow CMAKE_OSX_SYSROOT to be a logical SDK
name, 2012-09-21) we support names like "macosx" or "macosx10.7" as the
specified value of CMAKE_OSX_SYSROOT. Extend the SDK name->path
conversion to save the original value and also convert into a temporary
variable for the Xcode generator. Re-implement the deployment target
sanity check to detect the version from the transformed path.
Since commit 230ea218 (OS X: Improve default CMAKE_OSX_SYSROOT
selection, 2012-09-21) we always set CMAKE_OSX_SYSROOT if any SDK is
found in order to support Makefile generator builds with Xcode >= 4.3
without the command-line tools installed. However, in the basic
POSIX-only case of the Makefile generator with command-line tools and no
CMAKE_OSX_ARCHITECTURES we should not select any SDK by default.
Xcode supports SDKROOT values that just name an SDK rather than
specifying the full path to it. Recognize these values and handle them.
For Xcode we just put the value directly in the generated project file.
For Makefile generators we ask xcodebuild to provide the full path to
the named SDK.
Suggested-by: Jason DiCioccio <jd@ods.org>
Simplify the search for OSX_DEVELOPER_ROOT and allow it to fail if no
"/Developer" exists. When it does exist, always find a MacOSX SDK
inside it to use as the default CMAKE_OSX_SYSROOT. Otherwise set
CMAKE_OSX_SYSROOT to empty.
Drop the last use of CMAKE_OSX_SYSROOT_DEFAULT. Replace internal
platform variable CMAKE_${lang}_HAS_ISYSROOT with a more general
CMAKE_${lang}_SYSROOT_FLAG variable. If the -isysroot flag exists and
CMAKE_OSX_SYSROOT points to an SDK (not "/") then always add it to
compiler command lines. This is already done in the Xcode IDE.
The GNU compiler information file tests for GNU >= 3.4 because earlier
versions do not have the flag. The version number test is not valid for
Clang compiler versions, but we know Clang supports the flag.
While Clang presents an almost identical interface to GNU there will be
some differences. Split the compiler information modules to allow
separate rules for Clang. Start by loading the GNU rules but leave a
place to add Clang-specific information.
Make the EXPECTED_HASH option take only a single value instead of two to
avoid handling sub-keyword arguments. This is also consistent with
URL_HASH in ExternalProject.
Some download URLs do not have the filename embedded in the url.
Add an interface to specify the local filename explicitly.
Suggested-by: James Goppert <james.goppert@gmail.com>
Use the registry entries that vsvars32.bat uses to detect the location of
MSBuild.exe in the framework directory. Invoke MSBuild with the option
/p:VisualStudioVersion=$version
so it knows from which VS version to load the system build rules. Teach
cmGlobalVisualStudio11Generator to set its ExpressEdition member using the
registry.
Clang has the same interface as GNU except that we do not need to test
for the deployment target and sysroot flags. Simply set variables
CMAKE_${lang}_HAS_ISYSROOT
CMAKE_${lang}_OSX_DEPLOYMENT_TARGET_FLAG
to true because every version of Clang available on OS X supports these
flags.
TLS has superseded SSL so rename the recently added file(DOWNLOAD) and
ExternalProject options using the newer terminology. Drop "CURLOPT"
from names because curl is an implementation detail.
This commit adds the ability to turn on and off ssl certificate
authority checking. It also adds the ability to specify a
certificate authority information file. This can be done
by setting global cmake variables CMAKE_CURLOPT_CAINFO_FILE
and or CMAKE_CURLOPT_SSL_VERIFYPEER in the project calling
ExternalProject_Add, or by passing those options to individual
ExternalProject_Add calls.
This triggered an unknown secondary bug when there is
no ABSOLUTE INSTALL file. This is fixed as well.
This is based on a fix of bug #0013468 from Viktor Dubrovsky.
...if the library file does not exist inside the .framework then do
not allow a library variable to be set to the path to the framework.
Force set it to NOTFOUND instead.
This enables CMake to create Makefiles targeting Windows CE devices.
CMake needs to be run within a cross compile command prompt and requires
a toolchain file which sets CMAKE_SYSTEM_NAME to "WindowsCE" and
optionally CMAKE_SYSTEM_VERSION.
In commit 485a940e (VS: Simplify MSVC version reporting, 2012-08-23) we
accidentally flipped the 0/1 values of MSVC_IDE. Flip them back and
teach the CheckCompilerRelatedVariables test to check the variable.
32b7c72 Merge branch 'cmake-platform-info-version' into msvc-compiler-info
f3ddfef Modernize MSVC compiler information files
485a940 VS: Simplify MSVC version reporting
32db033 VS: Remove support for "free" version 2003 tools
e5fee8a Store ABI detection results in compiler information files
3df81b4 Move CMAKE_<LANG>_COMPILER_WORKS to compiler information files
7195aca Make platform information files specific to the CMake version
Remove the old-style "Windows-cl.cmake" and its helper "cl.cmake". Load
the information through new-style "Platform/Windows-MSVC-<lang>.cmake"
files. Factor information common to C and CXX into a helper file
"Platform/Windows-MSVC.cmake" loaded from the per-language files.
Teach Windows-cl.cmake to use CMAKE_(C|CXX)_COMPILER_VERSION to set the
"MSVC##" and MSVC_VERSION variables. It no longer needs the IDE generator
to dictate the version or to detect the version by running the
command-line tool for NMake and Ninja generators. Drop configuration of
CMakeCPlatform.cmake and CMakeCXXPlatform.cmake from Windows-cl.cmake.in
because all the results it saved are now cheap to compute every time.
Drop use of cache entry CMAKE_DETERMINE_<LANG>_ABI_COMPILED and replace
it with variable CMAKE_<LANG>_ABI_COMPILED. Since the grandparent
commit this test result is specific to the version of CMake. Store it
in the version-specific compiler information files instead of
CMakeCache.txt so testing can be re-done to meet the requirements of the
current version of CMake even if another version of CMake was already
used to configure the build tree.
403ead6 Document CMAKE_<LANG>_COMPILER_(ID|VERSION) values
8be51f6 Test variables CMAKE_(C|CXX|Fortran)_COMPILER(|_ID|_VERSION)
ec22a9b Cleanly enable a language in multiple subdirectories
66cb335 VS: Detect the compiler id and tool location
89595d6 VS10: Define CMAKE_VS_PLATFORM_TOOLSET variable
965a69d Xcode: Detect the compiler id and tool location
9a9e1ee CMakeDetermineCompilerId: Prepare to detect IDE compiler id
b8b5c83 Re-order C/C++/Fortran compiler determination logic
e9bc502 Detect Analog VisualDSP++ compiler version with its id
cca386b Detect Cray compiler version with its id
622d9a7 Detect SDCC compiler version with its id
4ad7fa6 Detect Comeau compiler version with its id
952651c Detect TI compiler version with its id
74c57d9 Detect PathScale compiler version with its id
707aefd Detect Compaq compiler version with its id
Since the parent commit this test result is specific to the version of
CMake. Store it in the version-specific compiler information files
instead of CMakeCache.txt so testing can be re-done to meet the
requirements of the current version of CMake even if another version of
CMake was already used to configure the build tree.
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.
Several more recent Visual Studio Express editions are now available and
they support debug builds. Simplify our VS platform files by removing
support for these old tools. If anyone still uses them we can restore
support with a more modern way to test for them.
Configure a hand-generated Visual Studio project to build the compiler id
source file since we cannot run the compiler command-line tool directly.
Add a post-build command to print out the full path to the compiler tool.
Parse the full path to the compiler tool from the build output.
Configure a hand-generated Xcode project to build the compiler id source
file since we cannot run the compiler command-line tool directly. Add a
post-build shell script phase to print out the compiler toolset build
setting. Run xcodebuild to compile the identification binary. Parse
the full path to the compiler tool from the xcodebuild output.
Teach CMAKE_DETERMINE_COMPILER_ID to check for variable
CMAKE_${lang}_COMPILER_ID_TOOL after CMAKE_DETERMINE_COMPILER_ID_BUILD
to use as CMAKE_${lang}_COMPILER since it will not be known until after
the IDE runs.
In CMAKE_DETERMINE_COMPILER_ID_BUILD prepare a cascading "if" so we can
use a generator-specific method to compile the identification source
file. Leave "if(0)" as a placeholder for now and put the direct
compiler invocation in "else()". After running the compiler to build
the compiler identification source we file(GLOB) the list of output
files as candidates for extracting the compiler information. An IDE may
create directories, so exclude exclude directories from this list.
Re-organize CMakeDetermine(C|CXX|Fortran)Compiler.cmake to search for
the compiler command-line tool only under generators for which it makes
sense. For the Visual Studio generators we do not expect to find the
compiler tool from the environment, nor would we use the result anyway.
Furthermore, set CMAKE_${lang}_COMPILER_ID_TEST_FLAGS only when it has a
chance to be used. Extract _CMAKE_TOOLCHAIN_LOCATION from the compiler
path after running the compiler id step so in the future that step can
help find the path to the compiler.
Commit 4be67837 (read less from version headers into variables,
2012-08-19) switched from file(READ) and string(REGEX MATCHALL) to just
file(STRINGS) to extract the list of resource <file> entries. However,
the latter extracts entire lines that match the regex, not just the part
that matches the regex, so the subsequent string(REGEX REPLACE) fails to
match and replace anything. Return to the original parsing logic but
replace file(READ) with file(STRINGS) to load a minimal part of the file
before using string(REGEX MATCHALL) as before.
Added a new CUDA variable for specifying the CUDA_HOST_COMPILER. This will allow users to
be able to specify which host compiler to use for invoking NVCC with. By default it will
use the compiler used for host compilation. This is convenient for when you want to
specify a different compiler than the default compiler. You end up using the same
compiler for both the NVCC compilation and the host compilation instead of using the
default compiler in the path for NVCC.
a3815e6 -fix line length
9110d0e Eclipse on OSX: improve handling of framework include dirs (#13367)
d97b385 Eclipse on OSX: fix handling of framework include dirs (#13464)
Instead of reading the whole file using file(READ) and later matching on the
whole file use file(STRINGS ... REGEX) to get only those lines we are
interested in at all. This will make the list much smaller (good for debugging)
and also the regular expressions will need to match on much smaller strings.
Also unset the content variables once they are not used anymore.
The Spanish language MFC localization dll changed names from
VS 9 to 10. Use the correct file name ending with "esn.dll"
instead of the now non-existent one ending with "esp.dll"
Also, add the existing, but missing from our rules until now,
Russian language module.
Alphabetize the list while we're at it for easier reading in
the future.
We may want to consider adding some file(GLOB code here to
minimize the risk of missing files added in future versions
of VS.
On OSX, the output from gcc looks like this:
/usr/include/c++/4.2.1
/usr/include/c++/4.2.1/i686-apple-darwin10/x86_64
/usr/include/c++/4.2.1/backward
/usr/lib/gcc/i686-apple-darwin10/4.2.1/include
/usr/include
/System/Library/Frameworks (framework directory)
/Library/Frameworks (framework directory)
End of search list.
The "(framework directory)" part needs to be removed so that Eclipse handles it properly
Alex
Remove old search paths that aren't needed.
Keep using PATHS instead of HINTS because a Windows machine may have
a different Qt in its PATH and putting QTDIR and the registry entry
ahead of PATH could cause apps to fail when run.
Add options HG_REPOSITORY and HG_TAG to specify an external project
hosted in a Mercurial repository. Teach ExternalProject to clone the
repository and update from it. Extend the ExternalProject test to try a
Mercurial repository when hg is available.
Previously, it was inconsistent in that some platforms/compilers
had this flag for the RelWithDebInfo configuration and some didn't.
This fixes issue #11366.
Since commit 571dc748 (Recognize Clang C and C++ compilers, 2010-05-17)
we recognize Clang C and C++ support. Add Compiler/Clang-ASM.cmake to
enable use of Clang for ASM too. Also teach Assembler test to try Clang
as an assembler.
Suggested-by: Tobias Pape <tobiaspape@gmail.com>
Especially remove "lib64" when the given paths are all Unix ones and "lib" is
also explicitely given. In that case CMake will search "lib64" anyway for
platforms where it is known to make sense.
Instead of directly passing $ENV{SOMEVAR} to a find_* call pass in ENV SOMEVAR.
This will make sure the paths will get correctly handled through different
platforms, especially on Windows.
Also fixes one place where paths with windows delimiters (\) were hardcoded to
use forward slashes.
This was missed by commit 7bbaa428 (Remove trailing whitespace from most
CMake and C/C++ code, 2012-08-13) which only removed trailing spaces,
not TABs.
Ancient versions of CMake required else(), endif(), and similar block
termination commands to have arguments matching the command starting the
block. This is no longer the preferred style.
Run the following shell code:
for c in else endif endforeach endfunction endmacro endwhile; do
echo 's/\b'"$c"'\(\s*\)(.\+)/'"$c"'\1()/'
done >convert.sed &&
git ls-files -z -- bootstrap '*.cmake' '*.cmake.in' '*CMakeLists.txt' |
egrep -z -v '^(Utilities/cm|Source/kwsys/)' |
egrep -z -v 'Tests/CMakeTests/While-Endwhile-' |
xargs -0 sed -i -f convert.sed &&
rm convert.sed
7e58e5b Prefer generic system compilers by default for C, C++, and Fortran
796e337 Factor common code out of CMakeDetermine(ASM|C|CXX|Fortran)Compiler
b708f1a CMakeDetermine(C|CXX)Compiler: Consider Clang compilers
Since commit c198730b (Detect Watcom compiler version with its id,
2011-12-07) the CMAKE_(C|CXX)_COMPILER_VERSION variables are set for the
Watcom compiler. Use these in Windows-wcl386.cmake to set the old
WATCOM1* version variables. This avoids using the old EXECUTE_PROCESS
command which failed due to extra quotes anyway.
This fix bug #0013451. The bug prevents theorerically relocatable RPM package
to be installed properly.
Signed-off-by: Eric NOULARD <eric.noulard@gmail.com>
Teach CMake to prefer the system default compiler automatically when no
compiler is specified. By default use "cc" for C, "CC" for C++, and
"f95" for Fortran. Load a new Platform/<os>-<lang>.cmake module to
allow each platform to specify for each language its system compiler
name(s) and/or exclude certain names.
Create Platform/(CYGWIN|Darwin|Linux|Windows)-CXX.cmake modules to
specify "c++" as the system C++ compiler name for these platforms. On
systems that use case-insensitive filesystems exclude C++ compiler names
that are distinguished from C compiler names only by case.
This will change the default compiler selection for existing build
scripts that do not specify a compiler when run on machines with
separate system and GNU compilers both installed in the PATH. We do not
make this change in default behavior lightly. However:
(1) If a given build really needs specific compilers one should specify
them explicitly e.g. by setting CC, CXX, and FC in the environment.
(2) The motivating case is to prefer the system Clang on newer OS X
systems over the older GNU compilers typically also installed. On
such systems the names "cc" and "c++" link to Clang. This is the
first platform known to CMake on which "c++" is not a GNU compiler.
The old behavior selected "gcc" for C and "c++" C++ and therefore
chooses GNU for C and Clang for C++ by default. The new behavior
selects GNU or Clang consistently for both languages on older or
newer OS X systems, respectively.
(3) Other than the motivating OS X case the conditions under which the
behavior changes do not tend to exist in default OS installations.
They typically occur only on non-GNU systems with manually-installed
GNU compilers.
(4) The consequences of the new behavior are not dire. At worst the
project fails to compile with the system compiler when it previously
worked with the non-system GNU compiler. Such failure is easy to
work around (see #1).
In short this change creates a more sensible default behavior everywhere
and fixes poor default behavior on a widely-used platform at the cost of
a modest change in behavior in less-common conditions.
The compiler candidate list selection and search code for C, C++, ASM,
and Fortran languages was duplicated across four modules. To look for
compilers adjacent to already-enabled languages the C and CXX modules
each used _CMAKE_USER_(C|CXX)_COMPILER_PATH and the ASM module used
_CMAKE_TOOLCHAIN_LOCATION. Since commit 4debb7ac (Bias Fortran compiler
search with C/C++ compilers, 2009-09-09) CMake prefers Fortran compilers
matching the vendor and directory of an enabled C or C++ compiler.
Factor out the common functionality among the four languages into a new
CMakeDetermineCompiler module. Generalize the Fortran implementation so
that all languages may each use the vendor and directory of the other
languages that have already been enabled. For now do not list any
vendor-specific names for C, C++, or ASM so that only the directory
preference is used for these languages (existing behavior).
Look for "clang" or "clang++" compiler executables so Clang will be used
when it is the only compiler available. Prefer them last to avoid
changing compiler default preferences for existing scripts.
In case that any of the input variables that hold the library names contains
more than just a single library the "debug" or "optimized" keywords were only
prepended to the first item, making all other libs appear in all
configurations. Just treat both input variables as lists.
Thanks to Philipp Berger <newsletters@philippberger.de> for pointing me at
this.
4bb94c9 Ninja: sysconf() is declared in unistd.h
bb36759 Ninja: enable response file support on Mac (length 262144)
3a2c8e8 Ninja: disable work around when linking with mingw
3856e66 Ninja: error on missing rspfile_content
8c1e35c Ninja: remove some unused default arguments
7f647cf Ninja: also write link libraries to rsp file