MSVC now supports the __is_assignable type trait intrinsic,
to enable easier and more efficient implementation of the
Standard Library's is_assignable trait.
As of Visual Studio 2015 Update 3, the VC Standard Library
implementation uses the new intrinsic unconditionally.
The implementation is pretty straightforward due to the previously
existing is_nothrow_assignable and is_trivially_assignable.
We handle __is_assignable via the same code as the other two except
that we skip the extra checks for nothrow or triviality.
Patch by Dave Bartolomeo!
Differential Revision: http://reviews.llvm.org/D20492
llvm-svn: 270458
r218292 reverted r197496 because it broke things. In addition to breaking
things, r197496 also made all traits starting with __is_ revertible.
Reinstantiate that part of r197496 because code out there (e.g. libc++) depends
on this behavior. Fixes PR21045.
llvm-svn: 218365
Changed from:
keyword '__is_empty' will be treated as an identifier for the remainder of the translation unit
To:
keyword '__is_empty' will be made available as an identifier for the remainder of the translation unit
This is a more accurate description of clang's keyword compatibility feature,
given that some of the keywords are turned into context-sensitive keywords
(e.g. REVERTIBLE_TYPE_TRAIT) rather than being fully disabled.
llvm-svn: 196776
clang converts keywords to identifiers for compatibility with various system
headers such as GNU libc.
Implement a -Wkeyword-compat extension warning to diagnose those cases. The
warning is on by default but will generally be ignored in system headers. It
can however be enabled globally to aid standards conformance testing.
This also changes the __uptr keyword avoidance from r195710 to no longer
special-case system headers, bringing it in line with other similar workarounds
in clang.
Implementation returns bool for symmetry with token annotation functions.
Some examples:
warning: keyword '__is_pod' will be treated as an identifier for the remainder of the translation unit [-Wkeyword-compat]
struct __is_pod
warning: keyword '__uptr' will be treated as an identifier here [-Wkeyword-compat]
union w *__uptr;
llvm-svn: 196212
that provides the behavior of the C++11 library trait
std::is_trivially_constructible<T, Args...>, which can't be
implemented purely as a library.
Since __is_trivially_constructible can have zero or more arguments, I
needed to add Yet Another Type Trait Expression Class, this one
handling arbitrary arguments. The next step will be to migrate
UnaryTypeTrait and BinaryTypeTrait over to this new, more general
TypeTrait class.
Fixes the Clang side of <rdar://problem/10895483> / PR12038.
llvm-svn: 151352
-There are 2 instances that change the TokenID for GNU libstdc++ 4.2 compatibility.
To handler those cases introduce a RevertedTokenID bitfield, RevertTokenIDToIdentifier() and hasRevertedTokenIDToIdentifier() methods.
Store the bitfield in PCH.
llvm-svn: 110868
David Majnemer