26 KiB
Platform and library support for Trompeloeil
- Using libc++ with Trompeloeil
- Using sanitizers with Trompeloeil
- Compiler versions in sample Linux distributions
- Tested configurations
- Testing Trompeloeil on Artful Aardvark (Ubuntu 17.10)
- Supporting incomplete standard libraries
Using libc++ with Trompeloeil
On some distributions clang is configured to use libstdc++-v3 as the
implementation of the C++ Standard Library. In order to use libc++,
pass the -stdlib=libc++ command line flag to the compiler.
For example,
clang++-5.0 -std=c++14 -stdlib=libc++ <other command line arguments>
To use libc++ with g++ a few more command line flags need to be passed.
This is a command line known to work with g++-6,
g++-6 -std=c++14 -nostdinc++ -isystem/usr/include/c++/v1 \
<other command line arguments> \
-nodefaultlibs -lc++ -lc++abi -lm -lc -lgcc_s -lgcc
Using sanitizers with Trompeloeil
Trompeloeil test cases have been compiled and run without error with AddressSanitizer (ASan), Undefined Behavior Sanitizer (UBSan) and Thread Sanitizer (TSan).
Feel free to add -fsanitize=address, -fsanitize=thread or
-fsanitize=undefined to your compiler command lines, especially
when unit testing.
Maybe your compiler supports -fsanitize-address-use-after-scope.
Add that flag as well.
Compiler versions in sample Linux distributions
Ubuntu
Canonical supports the main component of the repositories of a release.
Canonical does not support the universe component. Support for universe
is provided by the Ubuntu community. If a compiler or library is in universe
for a particular release, then there is no guarantee that there will be a
release of that compiler or library in the next or any future release of
Ubuntu, let alone updates in the current release.
Either migrate compilers and libraries with each Ubuntu release or take
control of your toolchain and remove a dependency on the platform. In the
latter case you then have the option of supporting the Ubuntu community
with a contribution of your toolchain to universe.
For more information, see
ubuntu.com, "Repositories"
Available: https://help.ubuntu.com/community/Repositories
Accessed: 29 October 2017
In summary
Trusty Tahr Xenial Xerus Zesty Zapus Artful Aardvark Bionic Beaver
(14.04LTS) (16.04LTS) (17.04) (17.10) (18.04LTS)
Released 2014-04-17 2016-04-21 2017-04-17 2017-10-19 2018-04
Supported to 2019-04 2021-04 2018-01 2018-07 2023-04
Compiler(s) g++-4.8.4 g++-5 g++-6 g++-7 TODO
clang++-3.5 clang++-4.0 clang++-4.0 universe TODO
clang++-5.0 TODO
libc++-dev universe universe universe universe TODO
1.0~svn199600-1 3.7.0 3.9.1 3.9.1 TODO
In detail
Trusty Tahr Xenial Xerus Zesty Zapus Artful Aardvark Bionic Beaver
(14.04LTS) (16.04LTS) (17.04) (17.10) (18.04LTS)
Released 2014-04-17 2016-04-21 2017-04-17 2017-10-19 2018-04
Supported to (2019-04) (2021-04) (2018-01) (2018-07) (2023-04)
GCC
g++-4.8 ports universe universe universe TODO
4.8.2-19ubuntu1 4.8.5-4ubuntu2 4.8.5-4ubuntu4 4.8.5-4ubuntu6 TODO
security xenial-updates zesty-updates TODO
4.8.4-2ubuntu1~14.04.3 N/A N/A TODO
trusty-updates xenial-backports zesty-backports TODO
4.8.4-2ubuntu1~14.04.3 N/A N/A TODO
trusty-backports
N/A
g++-4.9 main universe universe universe TODO
N/A 4.9.3-13ubuntu2 4.9.4-2ubuntu1 N/A TODO
trusty-updates xenial-updates zesty-updates TODO
N/A N/A N/A TODO
trusty-backports xenial-backports zesty-backports TODO
N/A N/A N/A TODO
g++-5 main ports universe universe TODO
N/A 5.3.1-14ubuntu2 5.4.1-8ubuntu1 5.5.0-1ubuntu1 TODO
trusty-updates security zesty-updates TODO
N/A 5.4.0-6ubuntu1~16.04.4 N/A TODO
trusty-backports xenial-updates zesty-backports TODO
N/A 5.4.0-6ubuntu1~16.04.5 N/A TODO
xenial-backports
N/A
g++-6 main main ports universe TODO
N/A N/A 6.3.0-8ubuntu1 6.4.0-8ubuntu1 TODO
trusty-updates xenial-updates main TODO
N/A N/A 6.3.0-12ubuntu2 TODO
trusty-backports xenial-backports zesty-updates TODO
N/A N/A N/A TODO
zesty-backports
N/A
g++-7 main main main main TODO
N/A N/A N/A 7.2.0-8ubuntu3 TODO
trusty-updates xenial-updates xenial-updates TODO
N/A N/A N/A TODO
trusty-backports xenial-backports xenial-backports TODO
N/A N/A N/A TODO
Clang
clang-3.5 ports universe N/A N/A TODO
1:3.5~svn201651-1ubuntu1 1:3.5.2-3ubuntu1 N/A N/A TODO
security xenial-updates zesty-updates TODO
1:3.5-4ubuntu2~trusty2 N/A N/A TODO
trusty-updates xenial-backports zesty-backports TODO
1:3.5-4ubuntu2~trusty2 N/A N/A TODO
trusty-backports
N/A
clang-3.6 N/A universe N/A N/A TODO
N/A 1:3.6.2-3ubuntu2 N/A N/A TODO
trusty-updates/universe xenial-updates zesty-updates TODO
1:3.6-2ubuntu1~trusty1 N/A N/A TODO
trusty-backports xenial-backports zesty-backports TODO
N/A N/A N/A TODO
clang-3.7 N/A universe universe N/A TODO
N/A 1:3.7.1-2ubuntu2 1:3.7.1-3ubuntu4 N/A TODO
trusty-updates xenial-updates zesty-updates TODO
N/A N/A N/A TODO
trusty-backports xenial-backports zesty-backports TODO
N/A N/A N/A TODO
clang-3.8 security universe universe universe TODO
1:3.8-2ubuntu3~trusty5 1:3.8-2ubuntu1 1:3.8.1-18ubuntu1 1:3.8.1-24ubuntu7 TODO
trusty-updates/universe xenial-updates/universe zesty-updates TODO
1:3.8-2ubuntu3~trusty5 1:3.8-2ubuntu4 N/A TODO
trusty-backports xenial-backports zesty-backports TODO
N/A N/A N/A TODO
clang-3.9 security security ports universe TODO
1:3.9.1-4ubuntu3~14.04.3 1:3.9.1-4ubuntu3~16.04.2 1:3.9.1-5ubuntu1 1:3.9.1-17ubuntu1 TODO
trusty-updates/universe xenial-updates/universe security TODO
1:3.9.1-4ubuntu3~14.04.3 1:3.9.1-4ubuntu3~16.04.2 1:3.9.1-5ubuntu1.1 TODO
trusty-backports xenial-backports zesty-updates TODO
N/A N/A 1:3.9.1-5ubuntu1.1 TODO
zesty-backports TODO
N/A TODO
clang-4.0 N/A security main universe TODO
N/A 1:4.0-1ubuntu1~16.04.2 1:4.0-1ubuntu1 1:4.0.1-6 TODO
trusty-updates xenial-updates zesty-updates TODO
N/A 1:4.0-1ubuntu1~16.04.2 N/A TODO
trusty-backports xenial-backports zesty-backports TODO
N/A N/A N/A TODO
clang-5.0 N/A N/A N/A universe TODO
N/A N/A N/A 1:5.0-3 TODO
trusty-updates xenial-updates zesty-updates TODO
N/A N/A N/A TODO
trusty-backports xenial-backports zesty-backports TODO
N/A N/A N/A TODO
libc++-dev
1.0 universe
1.0~svn199600-1
trusty-updates
N/A
trusty-backports
N/A
3.7 universe
3.7.0-1
xenial-updates/universe
3.7.0-1ubuntu0.1
xenial-backports
N/A
3.9 ports universe
3.7.0-1 3.9.1-3
universe
3.9.1-2
zesty-updates
N/A
zesty-backports
N/A
4.0 TODO
TODO
5.0 TODO
TODO
Table first compiled: 28 October 2017. Last updated: 28 October 2017.
Fedora
A short list of Fedora releases tells a similar story to the Ubuntu distribution.
25 26 27 28
Released 2016-11-22 2017-07-11 (2017-11-14) (2018-05-01)
Supported to TODO TODO TBD TBD
gcc-c++ 6.4.1-1.fc25 7.2.1-2.fc26 7.2.1-2.fc27 TODO
g++ 6.4.1 20170727 7.2.1 20170915 7.2.1 20170915 TODO
(Red Hat 6.4.1-1) (Red Hat 7.2.1-2) (Red Hat 7.2.1-2)
clang 3.9.1-2.fc25 4.0.1-5.fc26 4.0.1-5.fc27 TODO
clang++ 3.9.1 4.0.1 4.0.1 TODO
(tags/RELEASE_391/final (tags/RELEASE_401/final) (tags/RELEASE_401/final)
libcxx-devel 3.9.1-1.fc25 4.0.1-3.fc26 4.0.1-3.fc27 TODO
Table first compiled: 28 October 2017 Last updated: 9 November 2017
Tested configurations
Before release, Trompeloeil is tested with the following configurations of compiler, language dialect, and standard library.
GCC
Last updated: 3 June 2019
Key:
N/A: The combinationg++-4.8/c++11/libc++leads to compile errors and is not currently supported. Further investigation may change this outcome.--: The version oflibstdc++-v3lacks a definition of the_GLIBCXX_RELEASEmacro.stdc++meanslibstdc++-v3from GCC.c++meanslibc++from Clang.
g++-latest means the "live at head" build of g++.
Compiler Mode stdc++ c++
-std= __GLIBCXX__ _GLIBCXX_RELEASE _LIBCPP_VERSION
---------- ---- ------------------------------ ---------------
g++-4.8 c++11 20150623 -- N/A
g++-4.9 c++11 20160726 -- 8000
c++14
g++-5 c++11 20171010 -- 8000
c++14
c++17
g++-6 c++11 20181026 -- 8000
c++14
c++17
g++-7 c++11 20190326 7 8000
c++14
c++17
g++-8 c++11 20190406 8 8000
c++14
c++17
c++2a
g++-9 c++11 20190402 9 8000
c++14
c++17
c++2a
g++-latest c++11 20190421 9 8000
c++14
c++17
c++2a
Clang
clang++-latest means the "live at head" version of clang++.
Compiler Mode stdc++ c++
-std= __GLIBCXX__ _GLIBCXX_RELEASE _LIBCPP_VERSION
---------- ---- ------------------------------ ---------------
clang++-3.5 c++11 20190326 7 1101
c++14
clang++-3.6 c++11 20190326 7 1101
c++14
clang++-3.7 c++11 20190326 7 3700
c++14
clang++-3.8 c++11 20190326 7 3800
c++14
clang++-3.9 c++11 20190402 9 3900
c++14
clang++-4.0 c++11 20190402 9 4000
c++14
clang++-5.0 c++11 20190402 9 5000
c++14
c++17
c++2a
clang++-6.0 c++11 20190402 9 6000
c++14
c++17
c++2a
clang++-7 c++11 20190402 9 7000
c++14
c++17
c++2a
clang++-8 c++11 20190402 9 8000
c++14
c++17
c++2a
clang++-latest c++11 20190402 9 9000
c++14
c++17
c++2a
Microsoft Visual Studio
Last update: 3 June 2019
Tested with Visual Studio Community 2019 16.1.1 .
Platform Toolset Configuration Platform
------------------------- ------------- --------
Visual Studio 2015 (v140) Debug x64
Visual Studio 2017 (v141) Release x86
Visual Studio 2019 (v142)
Testing Trompeloeil on Artful Aardvark (Ubuntu 17.10)
The release of Artful Aardvark (Ubuntu 17.10) contains a number of issues
requiring workarounds if you want to compile and test Trompeloeil with
community supported compiler versions e.g. any version of clang++,
any version g++ less than 7, or community supported libraries e.g.
any version of libc++.
Canonical supported compilers and libraries -
just g++-7 with libstdc++-v3 - do not have the issues described below,
but this is rather a narrow list for testing Trompeloeil on its
supported compilers and libraries.
std::to_string() is not defined for some versions of libstdc++-v3
Affects: libstdc++-v3 from these packages
libstdc++-4.8-dev:amd64 4.8.5-4ubuntu6libstdc++-5-dev:amd64 5.5.0-1ubuntu1
Workaround: Add -D_GLIBCXX_USE_C99=1 to your compiler command lines.
Glibc 2.26 no longer supplies xlocale.h
The version of glibc in package libc6-dev (2.26-0ubuntu2)
drops support for xlocale.h.
libc++ tracked this change and supplied a fix for 5.0.
See: "Fix libcxx build with glibc 2.26+ by removing xlocale.h include."
Available: https://github.com/llvm-mirror/libcxx/commit/6e02e89f65ca1ca1d6ce30fbc557563164dd327e
Accessed: 11 November 2017
But Artful Aardvark ships package libc++-dev 3.9.1-3.
As a consequence, no software using libc++ out-of-the-box version
can compile on Artful.
Workaround: Create a symlink from locale.h to xlocale.h
cd /usr/include
sudo ln -s locale.h xlocale.h
Glibc 2.26 std::signbit() broken for GCC compilers < 6
A defect in GLIBC 2.26 prevents programs using signbit() from math.h
from compiling with g++-4.8, g++-4.9, or g++-5.
This happens to include any uses of libc++, which requires a
functioning signbit() to compile function template __libcpp_signbit()
in file math.h.
The Clang compilers happen to work with this part of glibc 2.26
as they don't implement 128-bit floating point and a different
code path is followed, even for the earliest supported compilers.
See: https://bugs.launchpad.net/ubuntu/+source/glibc/+bug/1725869
Workaround: Patch your local copy of math.h in glibc with the
fix from glibc upstream, found by following the links in this bug report:
See: "Bug 22296 - glibc 2.26: signbit build issue with Gcc 5.5.0 on x86_64"
Available: https://sourceware.org/bugzilla/show_bug.cgi?id=22296
Accessed: 11 November 2017
Conclusion
Hopefully updated packages for glibc (libc6-dev), libc++, and
libstdc++-dev for g++-4.8 and g++-5 will be released allowing
patch-free building and testing of Trompeloeil on Artful Aardvark.
A better strategy may be to build GLIBC, GCC 4.8, GCC 5.x, and libc++
from source and use these to build your software. Then consider
contributing your build to the Ubuntu Community; you just might be the
"support" in "community supported".
Supporting incomplete standard libraries
Some platforms, especially MCUs with RTOS, only have partial support for the
standard library <atomic> and <mutex> headers used by trompeloeil.
In many cases, it is possible to provide shims or custom implementations
of the necessary parts.
Replacing std::recursive_mutex
To use your own recursive mutex, define TROMPELOEIL_CUSTOM_RECURSIVE_MUTEX
either before including the Trompeloeil header
(e.g. #define TROMPELOEIL_CUSTOM_RECURSIVE_MUTEX) or as preprocessor
definition (e.g. GCC: -DTROMPELOEIL_CUSTOM_RECURSIVE_MUTEX).
Now define in one translation unit your custom recursive mutex for trompeloeil.
namespace trompeloeil {
std::unique_ptr<custom_recursive_mutex> create_custom_recursive_mutex() {
class custom : public custom_recursive_mutex {
void lock() override { mtx.lock(); }
void unlock() override { mtx.unlock(); }
private:
mylib::recursive_mutex mtx;
};
return std::make_unique<custom>();
}
}
Replacing std::atomic<T>
To use your own implementation of std::atomic<T>,
define TROMPELOEIL_CUSTOM_ATOMIC and make sure there is a header
trompeloeil/custom_atomic.hpp somewhere in the include search path.
This header should contain a class template trompeloeil::atomic<T>
that implements (part of) the interface of std::atomic<T>:
namespace trompeloeil
{
template <typename T>
class atomic
{
public:
atomic() : m_atomic()
{
}
explicit atomic(const T initial) : m_atomic(initial)
{
}
T operator=(T desired)
{
m_atomic.store(desired);
return m_atomic.load();
}
operator T() const
{
return m_atomic.load();
}
private:
mylib::atomic<T> m_atomic;
};
}
Replacing std::unique_lock<T>
To use your own implementation of std::unique_lock<T>,
define TROMPELOEIL_CUSTOM_UNIQUE_LOCK and make sure there is a header
trompeloeil/custom_unique_lock.hpp somewhere in the include search path.
This header should contain a class template trompeloeil::unique_lock<T>
that implements (part of) the interface of std::unique_lock<T>:
namespace trompeloeil
{
template <typename Mutex>
class unique_lock
{
public:
unique_lock() noexcept : m_mutex(nullptr)
{
}
explicit unique_lock(Mutex& mutex) : m_mutex(&mutex)
{
m_mutex->lock();
}
unique_lock(const unique_lock&) = delete;
unique_lock(unique_lock&& other) noexcept : m_mutex(nullptr)
{
std::swap(other.m_mutex, m_mutex);
}
unique_lock& operator=(const unique_lock&) = delete;
unique_lock& operator=(unique_lock&& other) noexcept
{
std::swap(other.m_mutex, m_mutex);
}
~unique_lock()
{
if (m_mutex)
{
m_mutex->unlock();
}
}
private:
Mutex* m_mutex;
};
}