MSVC has compiler warnings C4127 "conditional expression is constant" (enabled
by /W4) and C6326 "Potential comparison of a constant with another constant"
(enabled by /analyze). They're potentially useful, although they're slightly
annoying to library devs who know what they're doing. In the latest version of
the compiler, C4127 is suppressed when the compiler sees simple tests like
"if (name_of_thing)", so extracting comparison expressions into named
constants is a workaround. At the same time, using std::integral_constant
avoids C6326, which doesn't look at template arguments.
test/std/containers/sequences/vector.bool/emplace.pass.cpp
Replace 1 == 1 with true, which is the same as far as the library is concerned.
Fixes D28837.
llvm-svn: 292432
Adding `path::operator=(string_type&&)` made the expression `p = {}`
ambiguous. This path fixes that ambiguity by making the `string&&`
overload a template so it ranks lower during overload resolution.
llvm-svn: 292345
This is the subject of an active NB comment. Regardless of what the Working
Paper currently says, asking this question is morally wrong, because the
answer can change when the type is completed. C1XX now detects such
precondition violations and complains about them; perhaps Clang should too.
Fixes D28591.
llvm-svn: 292281
When support for `basic_string_view` was added to string it also
added new assignment operators from `basic_string_view`. These caused
ambiguity when assigning from a braced initializer. This patch fixes
that regression by making the basic_string_view assignment operator
rank lower in overload resolution by making it a template.
llvm-svn: 292276
In order to allow inlining of previously out-of-line functions without an ABI break
libc++ provides legacy definitions in the dylib that old programs can
continue to use. Unfortunatly Windows link.exe detects this hack and diagnoses the duplicate
definitions.
This patch disable the duplicate definitions on Windows by adding an ABI option
which disables all "legacy out-of-line symbols"
llvm-svn: 292190
Moves hot functions such as atomic add into the memory header file
so that they can be inlined, which brings performance benefits.
Patch by Kevin Hu, Aditya Kumar, Sebastian Pop
Differential Revision: https://reviews.llvm.org/D24991
llvm-svn: 292184
MSVC/clang-cl doesn't do a full EBO unless __declspec(empty_bases)
is applied to the derived type. This causes certain tuple tests
to fail.
This patch adds the empty_bases attribute to __tuple_impl in order
for tuple to fully provide the EBO.
llvm-svn: 292159
Summary: On Windows tests that use `_LIBCPP_ASSERT` fail to link because the assertion handler function isn't correctly exported from the libc++ dylib. This patch fixes the dll import/export issues by introducing a new visibility macro `_LIBCPP_EXTERN_VIS` for use on external variables.
Reviewers: compnerd, smeenai, EricWF
Reviewed By: EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D28728
llvm-svn: 292158
This patch contains multiple cleanups and fixes to better support building on
Windows.
* [Test] Fix handling of library runtime search paths by correctly adding them
to the PATH variable when running the tests.
* [Test] Don't explicitly force "--target=i686-pc-windows" when running the
test suite. Clang++ seems to deduce the correct target.
* [Test] Fix `.sh.cpp` tests on Windows by properly escaping flags used in
shell commands. Specifically windows style paths which included spaces
were causing these tests to fail.
* [CMake] Add "vcruntime" to the list of supported C++ ABI libraries in CMake, and
teach the test suite how to handle it. For now libc++ defaults to using
"vcruntime" on Windows except when libc++abi is in tree; That is probably
a bug and should be changed to always use vcruntime, at least for now.
* [Misc] Move the "c++-build" include directory to the libc++ binary dir
instead of the top level project dir and rename it "c++build". This is just
misc cleanup. Libc++ shouldn't be creating internal build files and directories
at the top-level projects root.
* [Misc] Build type_info's destructor when building for MSVC. This is a temporary
work around to prevent link errors until we have a proper type_info
implementation.
llvm-svn: 292157
We have already refactored the underlying platform thread type into
__libcpp_thread_t, but there are few places in the source where we
still assume it is an integral type.
This patch refactores those points back into the threading API.
Differential revision: https://reviews.llvm.org/D28608
Reviewers: EricWF
llvm-svn: 292107
Summary: This patch allows libc++ to be built against the debug MSVC runtimes instead of just the release ones.
Reviewers: rnk, majnemer, compnerd, smeenai
Subscribers: mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D28725
llvm-svn: 292006
Summary:
This patch attempts to fix the libc++ build/link so that it doesn't use an default C++ libraries on Windows. This is needed to prevent linking to MSVC's STL library.
Additionally this patch changes libc++ so that it is always linked with the non-debug DLL's (e.g. `/MD`). This is needed so that the test suite can correctly link the same libraries without needing to know which configuration `c++.dll` was linked with.
Reviewers: compnerd, rnk, majnemer, kimgr, awson, halyavin, smeenai
Subscribers: cfe-commits, mgorny
Differential Revision: https://reviews.llvm.org/D28441
llvm-svn: 292001
When -pedantic-errors is specified `__has_extension(<feature>)` is always
false when it would otherwise be true. This causes C++03 <atomic> to break
along with other issues.
This patch avoids the above problem by using __is_identifier(...) instead since
it is not affected by -pedantic-errors. For example instead of checking for
__has_extension(c_atomics) we now check `!__is_identifier(_Atomic)`, which
is only true when _Atomic is not a keyword provided by the compiler.
This patch applies similar changes to the detection logic for __decltype and
__nullptr as well.
Note that it does not apply this change to the C++03
`static_assert` macro since -Wc11-extensions warnings generated by expanding
that macro will appear in user code, and will not be suppressed as part of a
system header.
llvm-svn: 291995
This patch adjusts the out-of-tree CMake configuration so that
the stderr output is ignored when an old llvm-config is found
that doesn't support --cmakedir.
llvm-svn: 291991
Clang recently added a `diagnose_if(cond, msg, type)` attribute
which can be used to generate diagnostics when `cond` is a constant
expression that evaluates to true. Otherwise no attribute has no
effect.
This patch adds _LIBCPP_DIAGNOSE_ERROR/WARNING macros which
use this new attribute. Additionally this patch implements
a diagnostic message when a non-const-callable comparator is
given to a container.
Note: For now the warning version of the diagnostic is useless
within libc++ since warning diagnostics are suppressed by the
system header pragma. I'm going to work on fixing this.
llvm-svn: 291961