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.
Expect cxx_variadic_templates to implement N2555.
N2555 is essentially a bugfix and predates most compiler releases which
aimed to experimentally support variadic templates.
Record the availability of this feature for GNU 4.8 on (UNIX AND
NOT APPLE) only. In the future, availability can be recorded for
earlier GNU, for other platforms and for other compilers. Initially
the affected configurations are as restricted as possible to allow
for easy testing while extending the features vector in only one
dimension.
The error message when using the set_property API directly is not
very good, but follow up commits will provide origin debugging of
the property and a target_compile_features command which will
provide a configure-time backtrace when possible.
As CMAKE_ROOT_FIND_PATH can be a list, a new CMAKE_SYSROOT is
introduced, which is never a list.
The contents of this variable is passed to supporting compilers
as --sysroot. It is also accounted for when processing implicit
link directories reported by the compiler, and when generating
RPATH information.
Clang can compile code, but uses the gcc tools for other tasks such
as linking. The -gcc-toolchain option can be used for that, but
generalize so that other compilers can be treated the same.
If such a location is specified, use it as a hint for finding
the binutils executables.
For clang, this allows passing -target <triple> to the compiler, and
for qcc, -V<arch> using toolchain files containing something like
set(triple arm-linux-gnueabihf)
set(CMAKE_C_COMPILER "/usr/bin/clang")
set(CMAKE_C_COMPILER_TARGET ${triple})
set(CMAKE_CXX_COMPILER "/usr/bin/clang++")
set(CMAKE_CXX_COMPILER_TARGET ${triple})
or
set(arch gcc_ntoarmv7le)
set(CMAKE_C_COMPILER /opt/qnx650/host/linux/x86/usr/bin/qcc)
set(CMAKE_C_COMPILER_TARGET ${arch})
set(CMAKE_CXX_COMPILER /opt/qnx650/host/linux/x86/usr/bin/QCC)
set(CMAKE_CXX_COMPILER_TARGET ${arch})
Both clang and qcc are inherently cross compiler( driver)s.
When cross-compiling with clang, use the CMAKE_${lang}_COMPILER_TARGET
as the _CMAKE_TOOLCHAIN_PREFIX to find the appropriate binutils.
When cross-compiling with QNX qcc, use the CMAKE_${lang}_COMPILER_TARGET
to set the appropriate _CMAKE_TOOLCHAIN_PREFIX.
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
Apple distributes their own Clang build with their own version numbers
that differ from upstream Clang. Use the __apple_build_version__ symbol
to identify the Apple Clang compiler and report the Apple Build Version
as the fourth version component in CMAKE_<LANG>_COMPILER_VERSION. Add
Compiler/AppleClang-<lang> and Platform/Darwin-AppleClang-<lang> modules
that simply include the upstream equivalents.
Fix comparisons of CMAKE_<LANG>_COMPILER_ID to Clang in CMake's own
source and tests to account for AppleClang.
Teach the compiler identification preprocessor tests to report when
Clang simulates MSVC, and what version. If not MSVC, assume GNU.
Teach compiler information modules Clang-(C|CXX) to recognize when Clang
simulates MSVC and skip loading the GNU information.
Teach the Windows-MSVC platform information to recognize when it is
loaded as the simulated compiler and use that version information
instead of the real compiler's (different) version scheme.
Add platform modules Windows-Clang-(C|CXX) and support module
Windows-Clang to load either Windows-MSVC or Windows-GNU and wrap
the corresponding information macros.
For clang, this allows passing -target <triple> to the compiler, and
for qcc, -V<arch> using toolchain files containing something like
set(triple arm-linux-gnueabihf)
set(CMAKE_C_COMPILER "/usr/bin/clang")
set(CMAKE_C_COMPILER_TARGET ${triple})
set(CMAKE_CXX_COMPILER "/usr/bin/clang++")
set(CMAKE_CXX_COMPILER_TARGET ${triple})
or
set(arch gcc_ntoarmv7le)
set(CMAKE_C_COMPILER /opt/qnx650/host/linux/x86/usr/bin/qcc)
set(CMAKE_C_COMPILER_TARGET ${arch})
set(CMAKE_CXX_COMPILER /opt/qnx650/host/linux/x86/usr/bin/QCC)
set(CMAKE_CXX_COMPILER_TARGET ${arch})
Both clang and qcc are inherently cross compiler( driver)s.
As CMAKE_ROOT_FIND_PATH can be a list, a new CMAKE_SYSROOT is
introduced, which is never a list.
The contents of this variable is passed to supporting compilers
as --sysroot. It is also accounted for when processing implicit
link directories reported by the compiler, and when generating
RPATH information.
This corresponds to the g++ and clang++
option -fvisibility-inlines-hidden on linux. On Windows with MinGW,
this corresponds to -fno-keep-inline-dllexport. That option is
not supported by clang currently.
This is initialized by CMAKE_<LANG>_VISIBILITY_PRESET. The target
property is used as the operand to the -fvisibility= compile option
with GNU compilers and clang.
In GNU.cmake, -isystem is not used if APPLE is set. However, Clang has
pretty much always supported -isystem, so we should always use it.
In the future, GNU.cmake should do a version check to see if -isystem is
supported.
According to XL C/C++ V9.0 documentation the default for -qpic/-qnopic
is platform-dependent. It won't hurt to add the option on platforms
where it is the default, so always add it when we want position
independent code.
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.
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>
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"'\(\s*\)(.\+)/'"$c"'\1()/'
done >convert.sed &&
git ls-files -z -- bootstrap '*.cmake' '*.cmake.in' '*CMakeLists.txt' |
egrep -z -v '^(Utilities/cm|Source/kwsys/)' |
egrep -z -v 'Tests/CMakeTests/While-Endwhile-' |
xargs -0 sed -i -f convert.sed &&
rm convert.sed
Store in new platform variables
CMAKE_${lang}_COMPILE_OPTIONS_PIC
CMAKE_${lang}_COMPILE_OPTIONS_PIE
flags for position independent code generation.
In almost all cases, this means duplication of the
CMAKE_SHARED_LIBRARY_${lang}_FLAGS for the _PIC case and using the
assumed pie equivalent for the _PIE case. Note that the GNU compiler
has supported -fPIE since 3.4 and that there is no -fPIC on GNU for
Windows or Cygwin.
There is a possibility that the _PIE variables are not correct.
However, as there is no backwards compatibility to be concerned about
(as the POSITION_INDEPENDENT_CODE property is not used anywhere yet),
the current state suffices.
Add a boolean target property NO_SONAME which may be used to disable
soname for the specified shared library or module even if the platform
supports it. This property should be useful for private shared
libraries or various plugins which live in private directories and have
not been designed to be found or loaded globally.
Replace references to <CMAKE_SHARED_LIBRARY_SONAME_${LANG}_FLAG> and
hard-coded -install_name flags with a conditional <SONAME_FLAG> which is
expanded to the value of the CMAKE_SHARED_LIBRARY_SONAME_${LANG}_FLAG
definition as long as soname supports is enabled for the target in
question. Keep expanding CMAKE_SHARED_LIBRARY_SONAME_${LANG}_FLAG in
rules in case third party projects still use it. Such projects would
not yet use NO_SONAME so the adjacent <TARGET_SONAME> will always be
expanded. Make <TARGET_INSTALLNAME_DIR> NO_SONAME aware as well. Since
-install_name is soname on OS X, this should not be a problem if this
variable is expanded only if soname is enabled.
The Ninja generator performs rule variable substitution only once
globally per rule to put its own placeholders. Final substitution is
performed by ninja at build time. Therefore we cannot conditionally
replace the soname placeholders on a per-target basis. Rather than
omitting $SONAME from rules.ninja, simply do not write its contents for
targets which have NO_SONAME. Since 3 variables are affected by
NO_SONAME ($SONAME, $SONAME_FLAG, $INSTALLNAME_DIR), set them only if
soname is enabled.
Patch by Amine Khaldi!
Also, start using the -MT flag to set a target name for depfiles.
This works around a bug observed in distcc, as explained in the
comment. Based on a patch by Alexander Usov.
Causes compiler modules (currently only GNU) to set a
CMAKE_DEPFILE_FLAGS_${lang} variable, which communicates to
the generator the flags required to cause the compiler to create
dependency files.
Use the "-shared" option to link shared libraries. The compiler does
not support "-Wl," or "-rpath" but does know how to pass "-soname"
through to the linker.
90efed6 Xcode: Honor Fortran_FORMAT target and source file property
5c0c635 Fortran: Add support for free- and fixed-form flags
47a0c75 VS: Map Fortran free- and fixed-format flags to IDE options
d6e2a06 VS: Map per-source Fortran flags to IDE options
Define a "Fortran_FORMAT" target and source file property. Initialize
the target property from a "CMAKE_Fortran_FORMAT" variable. Interpret
values "FIXED" and "FREE" to indicate the source file format. Append
corresponding flags to the compiler command line.
Linking broken on non-AIX machines when using XL compilers due to those
machines not using the CreateExportList tool. Made use of this tool
conditional on finding it.
Fix typo introduced by commit e28c16b4 (Split GNU compiler information
files, 2009-12-02).
Reported-by: Campbell Barton <ideasman42@gmail.com>
Suggested-by: Michael Hertling <mhertling@online.de>
8bd3e51 Absoft: Enable FortranCInterface check in Fortran test
d7b376b Absoft: Detect implicit link libraries on Linux and Mac
ac5b999 Add Absoft Fortran compiler id and basic flags
The XL toolchain supports shared object files stored in archives. Since
CMake lists libraries on link lines by full path it is common for a
shared library link line to contain the path to an archive file.
When linking a shared library the compiler front-end by default runs
CreateExportList to construct the list of symbols to be exported.
Unfortunately it passes all files found on the command line to the tool
so archive and library files get processed along with the object files.
The tool returns a list of all symbols in all objects, archives, and
libraries on the command line. This causes the linker to copy every
object file out of every archive into the shared library whether they
are dependencies of the original object files or not.
Work around this problem by running CreateExportList ourselves with just
the original object files intended for inclusion in the shared library.
Then pass the list it produces on the link line to prevent the compiler
front-end from constructing its own. This tells the linker to export
only the symbols provided by the original source files of the shared
library.
Factor duplicate information out of Compiler/XL-<lang>.cmake modules
into a macro in a new Compiler/XL.cmake module. Invoke it from the
per-language files to produce the original settings.
Since commit e1729238 (Add initial XL C compiler flags for safer builds,
2009-09-30) CMake sets the initial XL C flags to include "-qthreaded"
and "-qhalt=e". Do the same for C++ and Fortran with this toolchain.
CMAKE_ASM_COMPILE_OBJECT is now so that it fits for GNU, Intel, HP and Sun
ASM_ATT had to be adjusted. Also adjusted the default
CMAKE_ASM_LINK_EXECUTABLE
Alex
This commit changes the way how the assembler support works in cmake.
The language "ASM" now always uses the C/Cxx compiler instead
of the assembler directly. This fixes#8392, assembler files are
not preprocessed.
If one wants to use the assembler directly, the specific
assembler "dialect" has to be enabled. I.e. to get as/gas,
you have to use now ASM-ATT, the same way for ASM_MASM and ASM_NASM.
Implemented this now for gcc.
SunStudio, IBM, HP and Intel still todo.
Alex
09d1c10 FortranCInterface: Recognize NAG Fortran module symbols
af2ad90 Add NAG Fortran compiler information files
24cc3d4 Recognize the NAG Fortran compiler
83892c4 Allow Fortran platform files to set empty values
fe3f878 Detect object files in implicit link information
On Linux the NAG Fortran compiler uses gcc under the hood to link. Use
"-Wl,-v" to pass "-v" to the underlying gcc compiler to get verbose link
output. Detect the NAG Fortran directory (using -dryrun) and then honor
object files in the directory referenced in the implicit link line.
Pass real linker options with "-Wl,-Xlinker,". The -Wl, gets through
the NAG front-end and the -Xlinker gets through the gcc front-end.
The Cray Fortran compiler needs "-em" to enable module output and also
"-J." to place the .mod files in the current working directory (instead
of next to the .o file).
Map to the platform and compiler information for GNU because the
compilers are command-line compatible for common operations. Later we
can add Clang-specific features as necessary. We honor the preferred
capitalization is "Clang", not the common mis-spelling "CLang".
We add compiler information files
Compiler/PathScale-<lang>.cmake
to specify PathScale compiler information for C, C++, and Fortran
languages. We use a macro in Compiler/PathScale.cmake to consolidate
the information common to all languages.
We factor flags from Platform/Linux-PGI-Fortran.cmake into language
independent helper modules
Compiler/PGI.cmake
Platform/Linux-PGI.cmake
and invoke the macros from
Compiler/PGI-<lang>.cmake
Platform/Linux-PGI-<lang>.cmake
This enables general support for the PGI compilers.
This moves GNU compiler flags into new-style modules
Compiler/GNU-<lang>.cmake
Platform/<os>-GNU-<lang>.cmake
We use language-independent helper modules
Compiler/GNU.cmake
Platform/<os>-GNU.cmake
to define macros consolidating the information.
This is a GNU-specific option that should not be specified for all
compilers on Linux. It tells the GNU compiler to pass -export-dynamic
to the linker to export symbols from executables for use by plugins.
Since we provide the ENABLE_EXPORTS target property to do the same thing
in a cross-platform way, there is no need to pass -rdynamic always.
Since the option is not useful for GNU tools and breaks other tools on
Linux we simply remove it from CMAKE_SHARED_LIBRARY_LINK_<lang>_FLAGS.
This also allows us to stop setting the variable in other Linux compiler
files just to erase the bad flag.
See issue #9985.
This commit teaches CMake about the g95 compiler from
http://www.g95.org
We use 'G95' as the compiler id string, and add some basic flags.
See issue #9241.
This commit adds some default initial C flags for the XL compiler. The
most important is "-qhalt=e" which causes the compiler to error-out on
non-severe error messages. This is necessary to get try-compiles to
fail when bad arguments are passed to a function.
This moves platform-independent XL compiler flags into separate
"Compiler/XL-<lang>.cmake" modules. Platform-specific flags go in
"Platform/<os>-XL-<lang>.cmake" modules.
The commit "Split Intel compiler information files" moved some Linux
specific flags into the platform-independent Intel compiler info files.
This moves them back.
This moves platform-independent SunPro compiler flags into separate
"Compiler/SunPro-<lang>.cmake" modules. Platform-specific flags are
left untouched.
IBM rebranded its VisualAge compiler to XL starting at version 8.0. We
use the compiler id "XL" for newer versions and "VisualAge" for older
versions. We now also recognize the "z/OS" compiler, which is distinct
from XL.
The CMAKE_Fortran_DEFINE_FLAG value applies to the IBM Fortran compilers
on all platforms. This moves the setting to the platform-independent
compiler information file.
We set the variables to contain "-v", the verbose front-end output
option for PGI compilers. This enables detection of implicit link
libraries and directories for these compilers.
We set the variables to contain "-v", the verbose front-end output
option for Intel compilers. This enables detection of implicit link
libraries and directories for these compilers.
This teaches CMake to detect implicit link information for C, C++, and
Fortran compilers. We detect the implicit linker search directories and
implicit linker options for UNIX-like environments using verbose output
from compiler front-ends. We store results in new variables called
CMAKE_<LANG>_IMPLICIT_LINK_LIBRARIES
CMAKE_<LANG>_IMPLICIT_LINK_DIRECTORIES
The implicit libraries can contain linker flags as well as library
names.