Due to MCST LCC compiler identification is now changed to LCC,
there should be a way for old projects to still identify it as GNU,
as it was before.
This commits adds the policy:
CMP0129: Compiler id for MCST LCC compilers is now LCC, not GNU.
This policy controls such a behavior.
OLD behaivior is to treat LCC as GNU, NEW is to treat is as LCC.
Divert LCC compiler as a new one, instead of treating it as GNU.
Since old times, Elbrus C/C++/Fortran Compiler (LCC) by MCST has been
passing checks for GNU compilers, so it has been identified as GNU.
Now, with intent of seriously upstreaming its support, it has been
added as a separate LCC compiler, and its version displays not a
supported GCC version, but LCC version itself (e.g. LCC 1.25.19 instead
of GNU 7.3.0).
This commit adds its support for detection, and also converts basically
every check like 'is this compiler GNU?' to 'is this compiler GNU or
LCC?'. The only places where this check is untouched, is where it
regards other platforms where LCC is unavailable (primarily non-Linux),
and where it REALLY differs from GNU compiler.
Note: this transition may break software that are already ported to
Elbrus, but hardly relies that LCC will be detected as GNU; still such
software is not known.
Since commit d44c0db0b2 (clang: setup correct configuration in gnu mode,
2019-02-20, v3.15.0-rc1~41^2~5) we support the GNU-like Clang that
targets the MSVC ABI. However, Clang cannot compile with the MSVC
standard library unless it runs in a mode aware of C++14 (since MSVC
itself does not even have a lower mode). When `CMAKE_CXX_STANDARD` is
set to 98 or 11, use C++14 anyway.
Since Clang's default mode is aware of C++14, another option is to not
add any flags for 98 or 11. However, if a future Clang version ever
defaults to a higher C++ standard, setting the standard to 98 or 11
should at least not use a mode higher than 14.
Also revert test updates from commit 4819ff9647 (Tests: fix failures
with gnu mode clang on windows, 2019-03-21, v3.15.0-rc1~41^2~3) that
were meant to work around the standard selection problem.
Fixes: #19496
Root causes were:
* Using incorrect conditions (assuming MSVC-like command line mode)
* Trying to compile the MSVC STL in C++11 mode, when parts of it require
C++14 or enabling MS extensions in clang.
* Missing flush in a testcase using stdout in a dll and a main part
with static crt
Previously compilers that only supported the meta-level flags
would not have any of the granular features listed. Now we
presume that they have full support and enable all the features.
Update granular feature tests to skip the actual compilation
checks for the presumed features.
* Disable the system include unused variable test in ExportImport when
clang is in MSVC compatible mode.
* Disable CxxDialect testcase when clang is in MSVC compatible mode, as
it doesn't support `typeof`.
* Teach Module.WriteCompilerDetectionHeader to treat clang-cl as MSVC.
* Disable the SystemIncludeDirectories testcase within
IncludeDirectories when clang is in MSVC compatible mode.
* Disable the CMakeOnly.CheckCXXCompilerFlag testcase when clang is in
MSVC compatible mode.
* Treat clang-cl as MSVC in LinkOptions.cmake in the try_run and
try_compile testcases.
Run the `clang-format.bash` script to update all our C and C++ code to a
new style defined by `.clang-format`. Use `clang-format` version 6.0.
* If you reached this commit for a line in `git blame`, re-run the blame
operation starting at the parent of this commit to see older history
for the content.
* See the parent commit for instructions to rebase a change across this
style transition commit.
This allows defining compat versions of some C/C++ features with the name of the
keyword itself, so all code can look as if it was written for the new language
standard.
This was broken in commit 98e6d1e5e4
(Tests/Module/WCDH: make it work with only C features defined) when all C tests
were made accessible even if no C++ features are available, but the header was
only created if C++ features are available. Fix it by creating the header
unconditionally before any checks on the available features.
This allows one to generate a header that will basically always work. In case
an unknown compiler or compiler version is encountered it simply falls back to
the unsupported case.
Run the `Utilities/Scripts/clang-format.bash` script to update
all our C++ code to a new style defined by `.clang-format`.
Use `clang-format` version 3.8.
* If you reached this commit for a line in `git blame`, re-run the blame
operation starting at the parent of this commit to see older history
for the content.
* See the parent commit for instructions to rebase a change across this
style transition commit.
Revert commit v3.4.0-rc1~10^2~2 (Features: Disable support for Oracle
SolarisStudio on non-Linux, 2015-09-29) and two follow-up commits.
The support of compile features and language standards on Orcale
SolarisStudio needs more investigation so for CMake 3.4 we should
just act as 3.3 did.
We do support SunPro 5.13 compiler features, but only on Linux.
Suppress the portion of the test that fails on Solaris until
the larger problem can be addressed.
This bug caused c_function_prototypes to not be recorded at configure
time when compiling with -std=gnu99 or similar. In the case of feature
recording, that was not a problem, because the logic in
CMakeDetermineCompileFeatures.cmake currently assumes that a feature
present for an earlier standard is present for a later standard.
However, the detection strings are also used in WriteCompilerDetectionHeader,
so the feature macro has been defined to '0' when using a later language
dialect.
Fix that by not checking the existence of the __STDC_VERSION__ macro at
all when detecting C90 features.
The CXX_STANDARD property validates the values allowed for it,
and '90' is not a valid value for it. However, the validation is only
done for languages enabled for the target, and as C_undefined has no
CXX files, that language is not enabled for it.
This amends commit v3.1.0-rc3~23^2 (WCDH: Make the header -Wundef
safe for the C language., 2014-11-24).
004e1540 Features: Record for GNU 4.4.
2a5ca650 Features: Wrap failure-test in UNIX condition.
1ae2c6b2 Features: Blacklist cxx_constexpr test for GNU 4.5.
c66e3317 Features: Use a more-common feature in cycle-test.
c43a6dc5 Features: Update comment in test to match the code.
78259135 Features: Test presence of cxx_auto_type with genex.
7b9fc88b Features: Remove outdated comment.
Revert commits:
2d738ce3 Help: Add notes for topic 'feature_record_msvc'
f73718c9 Features: Enable writing of MSVC compiler feature header.
64c30bdc Features: Record for MSVC C++ 2015 and MSVC C 2010-2015.
225c0ef8 Features: Record for MSVC 2010-2013.
This topic was merged to master prematurely, so remove it.
Notes:
VS2015 and above are the only MSVC versions to support cxx_final, so remove
usages from the tests, and instead only test for cxx_override.
VS2012 and above to conform to cxx_decltype_incomplete_return_types
proposal, but without support for auto return types the dcl.type.simple
example in the proposal doesn't compile.
VS2013 and above to conform to the updated cxx_contextual_conversions proposal,
but VS2010 and above pass the test.
Compilers such as MSVC have no explicit flags to enable C++11 mode,
it just is always on. So only run the link tests with compilers that require
a flag to specify the language version.
The __STDC_VERSION__ macro may be defined or not depending on the
implementation dialect of C. Test that it is defined before testing
its value.
The CXX tests do not need such a change because they define __cplusplus
in all dialects.
Extend the write_compiler_detection_header interface to allow
specifying a location for supplementary files, and getting the
list of resulting files as a variable.
Add properties and variables corresponding to CXX equivalents.
Add features for c_function_prototypes (C90), c_restrict (C99),
c_variadic_macros (C99) and c_static_assert (C11). This feature
set can be extended later.
Add a <PREFIX>_RESTRICT symbol define to WriteCompilerDetectionHeader
to conditionally represent the c_restrict feature.
Provide a function to write a portable header to detect compiler
features. Generate a preprocessor #error for unknown compilers
and compiler versions whose features are not yet recorded. This
error condition might be relaxed in the future, but for now it
is useful for verification of expectations.
