The RTTI structure is different on Windows when building under MS ABI.
Update the definition to reflect this. The structure itself contains an
area for caching the undecorated name (which is 0-initialized). The
decorated name has a bitfield followed by the linkage name. When
std::type_info::name is invoked for the first time, the runtime should
undecorate the name, cache it, and return the undecorated name. This
requires access to an implementation of __unDName. For now, return
the raw name.
This uses the fnv-1a hash to hash the name of the RTTI. We could use an
alternate hash (murmur? city?), but, this was the quickest to throw
together.
llvm-svn: 313344
Libc++ is used as a system library on macOS and iOS (amongst others). In order
for users to be able to compile a binary that is intended to be deployed to an
older version of the platform, clang provides the
availability attribute <https://clang.llvm.org/docs/AttributeReference.html#availability>_
that can be placed on declarations to describe the lifecycle of a symbol in the
library.
See docs/DesignDocs/AvailabilityMarkup.rst for more information.
Differential Revision: https://reviews.llvm.org/D31739
llvm-svn: 302172
This recommits r294707 with additional fixes. The main difference is
libc++ now correctly builds without any ABI library.
exception.cpp is a bloody mess. It's full of confusing #ifdef branches for
each different ABI library we support, and it's getting unmaintainable.
This patch breaks down exception.cpp into multiple different header files,
roughly one per implementation. Additionally it moves the definitions of
exceptions in new.cpp into the correct implementation header.
This patch also removes an unmaintained libc++abi configuration.
This configuration may still be used by Apple internally but there
are no other possible users. If it turns out that Apple still uses
this configuration internally I will re-add it in a later commit.
See http://llvm.org/PR31904.
llvm-svn: 294730
exception.cpp is a bloody mess. It's full of confusing #ifdef branches for
each different ABI library we support, and it's getting unmaintainable.
This patch breaks down exception.cpp into multiple different header files,
roughly one per implementation. Additionally it moves the definitions of
exceptions in new.cpp into the correct implementation header.
This patch also removes an unmaintained libc++abi configuration.
This configuration may still be used by Apple internally but there
are no other possible users. If it turns out that Apple still uses
this configuration internally I will re-add it in a later commit.
See http://llvm.org/PR31904.
llvm-svn: 294707
This is motivated by adding a third RTTI scheme to libc++. Split out
the two forms of the itanium RTTI representation. This is based on
suggestions from Eric Fiselier. NFC
llvm-svn: 291174
Summary:
The current implementation of `hash_code()` for uniqued RTTI strings violates strict aliasing by dereferencing a type-punned pointer. Specifically it generates a `const char**` pointer from the address of the `__name` member before casting it to `const size_t*` and dereferencing it to get the hash. This is really just a complex and incorrect way of writing `reinterpret_cast<size_t>(__name)`.
This patch changes the conversion sequence so that it no longer contains UB.
Reviewers: howard.hinnant, mclow.lists
Subscribers: rjmccall, cfe-commits
Differential Revision: https://reviews.llvm.org/D24012
llvm-svn: 283408
This patch removes the `<cstdlib>` include from exception where it is no longer
needed. Unlike my previous attempt this patch also adds <cstdlib> where needed
in other headers like <new> and <typeinfo>.
This won't fix the Firefox build issues discussed on IRC but it is more correct
for libc++.
llvm-svn: 280754
Apparently I missed a number of additional include which need to be added.
Reverting so I can recommit as a single patch with all of the required includes.
llvm-svn: 280752
Summary:
Currently a number of GCC warnings are emitted when building libc++. This patch fixes or ignores all of them. The primary changes are:
* Work around strict aliasing issues in `typeinfo::hash_code()` by using __attribute__((may_alias)). However I think a non-aliasing `hash_code()` implementation is possible. Further investigation needed.
* Add `_LIBCPP_UNREACHABLE()` to switch in `strstream.cpp` to avoid -Wpotentially-uninitialized.
* Fix -Wunused-value warning in `__all` by adding a void cast.
* Ignore -Wattributes for now. There are a number of real attribute issues when using GCC but enabling the warning is too noisy.
* Ignore -Wliteral-suffix since it warns about the use of reserved identifiers. Note Only GCC 7.0 supports disabling this warning.
* Ignore -Wc++14-compat since it warns about the sized new/delete overloads.
Reviewers: EricWF
Differential Revision: https://reviews.llvm.org/D24003
llvm-svn: 280007
It's identical to name() these days. (At one point it avoided masking
of the RTTI uniqueness bit because ARM64 ignored it architecturally,
but no longer).
llvm-svn: 205518
ARM64 generates RTTI with hidden visibility, which means that typeinfo
must be compared char-by-char since it's not guaranteed to be uniqued
across the whole program.
llvm-svn: 205139
Shoaib Meenai