An unpleasant surprise while migrating unique_ptrs (see changes in
lib/Object): ErrorOr<int*> was implicitly convertible to
ErrorOr<std::unique_ptr<int>>.
Keep the explicit conversions otherwise it's a pain to convert
ErrorOr<int*> to ErrorOr<std::unique_ptr<int>>.
I'm not sure if there should be more SFINAE on those explicit ctors (I
could check if !is_convertible && is_constructible, but since the ctor
has to be called explicitly I don't think there's any need to disable
them when !is_constructible - they'll just fail anyway. It's the
converting ctors that can create interesting ambiguities without proper
SFINAE). I had to SFINAE the explicit ones because otherwise they'd be
ambiguous with the implicit ones in an explicit context, so far as I
could tell.
The converting assignment operators seemed unnecessary (and similarly
buggy/dangerous) - just rely on the converting ctors to convert to the
right type for assignment instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217048 91177308-0d34-0410-b5e6-96231b3b80d8
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215558 91177308-0d34-0410-b5e6-96231b3b80d8
While std::error_code itself seems to work OK in all platforms, there
are few annoying differences with regards to the std::errc enumeration.
This patch adds a simple llvm enumeration, which will hopefully avoid build
breakages in other platforms and surprises as we get more uses of
std::error_code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210920 91177308-0d34-0410-b5e6-96231b3b80d8
This is a minimal change to remove the header. I will remove the occurrences
of "using std::error_code" in a followup patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210803 91177308-0d34-0410-b5e6-96231b3b80d8
There is no std::error_code::success, so this removes much of the noise
in transitioning to std::error_code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209952 91177308-0d34-0410-b5e6-96231b3b80d8
to the build being C++11.
There is clearly still plenty of simplification than can be done here by
using standard type traits instead of rolling our own in many places.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202586 91177308-0d34-0410-b5e6-96231b3b80d8
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.
Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198685 91177308-0d34-0410-b5e6-96231b3b80d8
One of the uses of the IsValid flag is to support default constructing
a ErrorOr that is not a Error or a Value. There is not much value in
doing that IMHO. If ErrorOr was to have a default constructor, it
should be implemented by default constructing the value, but even that
looks unnecessary.
The other use is to avoid calling destructors on moved objects. This
looks wrong. If the data being moved has non trivial treatment of
moves (an std::vector for example), it is its destructor that should
handle it, not ~ErrorOr.
With this change ErrorOr becomes a fairly simple wrapper and should
always be better than using an error_code + value in an API.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194109 91177308-0d34-0410-b5e6-96231b3b80d8
ErrorOr had quiet a bit of complexity and indirection to be able to hold a user
type with the error.
That feature is not used anymore. This patch removes it, it will live in svn
history if we ever need it again.
If we do need it again, IMHO there is one thing that should be done
differently: Holding extra info in the error is not a property a function also
returning a value or not. The ability to hold extra info should be in the error
type and ErrorOr templated over it so that we don't need the funny looking
ErrorOr<void>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194030 91177308-0d34-0410-b5e6-96231b3b80d8
Some paths through the copy constructors for 'ErrorOr' were calling
'get' when 'HasError' and 'IsValid' were not properly initialized.
Depending on what happened to be in memory for those member variables
the asserts in 'get' might incorrectly fire. Fixed by ensuring that
the member variables in question are always initialized before calling
'get'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174381 91177308-0d34-0410-b5e6-96231b3b80d8
ErrorOr<void> represents an operation that returns nothing, but can still fail.
It should be used in cases where you need the aditional user data that ErrorOr
provides over error_code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173209 91177308-0d34-0410-b5e6-96231b3b80d8
