pair, and a couple of pair-like implementation detail types. The
C++98/03 and 11 standards all specify that the copy constructor of
pair<int, int> is trivial. However as libc++ tracked the draft C++11
standard over the years, this copy constructor became non-trivial, and
then just recently was corrected back to trivial for C++11.
Unfortunately (for libc++1) the Itanium ABI specifies different calling
conventions for trivial and non-trivial copy constructors. Therefore
currently the C++03 libc++ copy constructor for pair<int, int> is ABI
incompatible with the C++11 libc++ copy constructor for pair<int, int>.
This is Bad(tm). This patch corrects the situation by making this copy
constructor trivial in C++03 mode as well.
Just in case it is needed for an incomplete C++11 compiler, libc++
retains the ability to support pair with rvalue references, but without
defaulted special members. However the pair needs non-trivial special
members to implement this special case, (as it did when clang was in
this place a couple of years ago).
During this work a bug was also found and fixed in
is_trivially_constructible.
And there is a minor drive-by fix in <__config> regarding
__type_visibility__.
A test is updated to ensure that the copy constructor of pair<int, int>
is trivial in both C++03 and C++11. This test will necessarily fail for
a compiler that implements rvalue references but not defaulted special
members.
llvm-svn: 194536
http://lab.llvm.org:8013/builders/libcxx_clang-x86_64-darwin11-RA
lit.py: <string>:230: note: inferred use_system_lib as: False
lit.py: <string>:247: fatal: C++ ABI setting None unsupported for tests
cxx_abi is geting set to None, and the lit script errors out shortly after
that. This patch changes the default of cxx_abi from None to 'libcxxabi'.
This is likely not the right way to fix this problem. However it gets the
buildbot running again. Improvements to this fix are welcome.
llvm-svn: 192609
libsupc++ does not implement the dependent EH ABI and the
functionality it uses to implement std::exception_ptr (which it
declares as an alias of std::__exception_ptr::exception_ptr) is not
directly exported to clients. So we have little choice but to hijack
std::__exception_ptr::exception_ptr's (which fortunately has the
same layout as our std::exception_ptr) copy constructor, assignment
operator and destructor (which are part of its stable ABI), and its
rethrow_exception(std::__exception_ptr::exception_ptr) function.
Also, remove some out of date comments.
Differential Revision: http://llvm-reviews.chandlerc.com/D1826
llvm-svn: 192076
Linking against libstdc++, rather than libsupc++, is probably better
for people who need to link against clients of libstdc++. Because
libsupc++ is provided only as a static library, its globals are not
shared between the static library and the copy linked into libstdc++.
This has been found to cause at least one test failure.
This also removes a number of symbols which were multiply defined
between libstdc++ and libc++, only when linking with libstdc++.
Differential Revision: http://llvm-reviews.chandlerc.com/D1825
llvm-svn: 192075
The remaining multiple definitions were flushed out by attempting to
link libsupc++ and libc++ into the same executable with --whole-archive,
e.g.
clang++ -I../llvm/projects/libcxx/include -nodefaultlibs -Wl,--whole-archive lib/libc++.a /usr/lib/gcc/x86_64-linux-gnu/4.6/libsupc++.a -Wl,--no-whole-archive -lgcc -lgcc_s -lc -lpthread -lrt
(The same technique was used to flush out multiple definitions in
libstdc++.)
Differential Revision: http://llvm-reviews.chandlerc.com/D1824
llvm-svn: 192074
I've changed it so we don't set highest level warnings (all) for MSVC when building projects using cmake and instead leave the default. That's /W4 on my machine and seems to be ok.
With all warnings on for msvc, we see literally thousands of warnings. 99.99% aren't relevant and just obscure the ones that are.
I think the user can still override things if they want something different from the command line when using cmake.
llvm-svn: 192010
The issue this patch seeks to address is that MS's compiler (cl.exe) doesn't support the __attribute__((__weak__)) or __atribute__((__visibility__("default")) syntax; so a solution must be found where cl.exe doesn't see this syntax.
This patch seeks to solve this problem by changing code patterned like this:
__attribute__((__weak__, __visibility__("default")))
void* operator new(size_t size, const std::nothrow_t&) _NOEXCEPT { /*snip*/; return p; }
to code like this:
_LIBCPP_WEAK
void* operator new(size_t size, const std::nothrow_t&) _NOEXCEPT { return p; }
Howard: Thanks for all the comments regarding the default visibility
tag on the definition. I agree it isn't needed, and that there are lots
of other places where it is missing. That being said, I'm not wanting
to rock the boat on that issue right now. So I've added it back to the
definition via _LIBCPP_FUNC_VIS. A later pass dedicated just to this
issue can bring things in to a consistent state one way or the other.
Note that we do not want to have the exact same attributes on the
declaration and defintion in this case. The declaration should not be
marked weak, whereas the definition should (which is what G M's patch
did). I've fully tested on OS X to ensure that the resultant attribute
syntax actually works.
llvm-svn: 192007