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.
Clang 3.4 uses C99 by default, and Clang 3.6 uses C11 by default:
http://thread.gmane.org/gmane.comp.compilers.clang.devel/39379
GNU 4.9 uses C90 by default, and GNU 5.0 uses C11 by default:
https://gcc.gnu.org/gcc-5/changes.html
Test that the default compiler settings result in the expected dialect
macros being defined for both C and CXX. Remove the unused main.c
file from the CompileFeatures unit test.
Features are currently recorded accidentally for all versions of
AppleClang > 3.4 (I have no idea how that relates to upstream
Clang). Presumably that version has the features which are
accidentally recorded, but in the future features will be
recorded initially for only AppleClang >= 5.1, which would
appear as a feature regression.
Commit v3.1.0-rc1~635^2~11 (Don't load Clang-CXX from
AppleClang-CXX., 2013-11-11) ajusted the logic for the CXX
language. Make a similar change for the C language.
The Fujitsu C/C++ compilers are the default ones for K computer.
Detect both native and cross compilers by looking for the __FUJITSU
preprocessor definition.
Commit v3.0.0-rc1~111^2 (QNX: Introduce QCC compiler id for that
QNX platform compiler., 2014-01-20) split handling of the QNX QCC
compiler into a separate compiler-id. That refactoring results in
the QCC compiler not using the CMake-compiler-id "GNU", which means
that the __compiler_gnu macro is no longer executed for it.
Add Compiler/QCC*.cmake modules to define and call the __compiler_qcc
macro and teach it to call __compiler_gnu internally. Remove the
corresponding pieces from the Platform/QNX*.cmake modules.
It is also necessary to change the language conditional to dereference
the lang macro parameter, which is another bug introduced by the
same commit. The extra -lang-c++ flag is only necessary when the CXX
compiler is specified as 'qcc' instead of 'QCC' in the toolchain file,
which is why this bug was not noticed before. The flag is also necessary
in that case when linking in order to find the appropriate standard
libraries. The flag was not previously added when linking executables,
so linking failed even with CMake 2.8.12 with the lower-case compiler-id.
Co-Author: Brad King <brad.king@kitware.com>
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.
Remove the use of check_cxx_source_compiles which is now just getting in
the way.
Blacklist the cxx_alignof feature in the test with GNU 4.7. The test
file compiles, but it is documented as available first in GNU 4.8.
205215fb cmTarget: Add CXX_STANDARD_REQUIRED to control decay.
1df2116b Features: Decay language flag if requested is not available.
c4f4dac2 Project: Fix exit-on-error with compile feature tests.
5bb7ce72 Project: Use nullary form of main for compile feature tests.
64254e7a Project: Remove extern from static string in feature tests.
0d9c99bf Help: Fix order of help entries.
dc7639bd Tests: Fix name of cache variable.
This will allow sharing of the logic of the order to test compilers in
and the preprocessor macros used to do that and to determine the
version components.
Use the highest standard compile flags available if requested language
version is too new.
This supports use-cases like
set(CMAKE_CXX_STANDARD 14)
# Compiled with -std=c++11 with GNU 4.7, which has no -std=c++14
# or equivalent flag
add_executable(main main.cpp)
This can be used in combination with preprocessor defines which
communicate the availability of certain language features for
optional use.
Old versions of aCC need a special compiler flag to get full C++98 template
support as e.g. CMake itself or the Complex and ComplexOneConfig tests need.
The same versions need a special flag to get a proper C++ library, too.
Stephen Kelly
Brad King
Fraser Hutchison
Tim Gallagher
Erik Lindahl
Rolf Eike Beer