[clang] Remove rdar links; NFC

We have a new policy in place making links to private resources
something we try to avoid in source and test files. Normally, we'd
organically switch to the new policy

[clang] Remove rdar links; NFC

We have a new policy in place making links to private resources
something we try to avoid in source and test files. Normally, we'd
organically switch to the new policy rather than make a sweeping change
across a project. However, Clang is in a somewhat special circumstance
currently: recently, I've had several new contributors run into rdar
links around test code which their patch was changing the behavior of.
This turns out to be a surprisingly bad experience, especially for
newer folks, for a handful of reasons: not understanding what the link
is and feeling intimidated by it, wondering whether their changes are
actually breaking something important to a downstream in some way,
having to hunt down strangers not involved with the patch to impose on
them for help, accidental pressure from asking for potentially private
IP to be made public, etc. Because folks run into these links entirely
by chance (through fixing bugs or working on new features), there's not
really a set of problematic links to focus on -- all of the links have
basically the same potential for causing these problems. As a result,
this is an omnibus patch to remove all such links.

This was not a mechanical change; it was done by manually searching for
rdar, radar, radr, and other variants to find all the various
problematic links. From there, I tried to retain or reword the
surrounding comments so that we would lose as little context as
possible. However, because most links were just a plain link with no
supporting context, the majority of the changes are simple removals.

Differential Review: https://reviews.llvm.org/D158071

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Revert "Remove rdar links; NFC"

This reverts commit d618f1c3b12effd0c2bdb7d02108d3551f389d3d.
This commit wasn't reviewed ahead of time and significant concerns were
raised immediately after it land

Revert "Remove rdar links; NFC"

This reverts commit d618f1c3b12effd0c2bdb7d02108d3551f389d3d.
This commit wasn't reviewed ahead of time and significant concerns were
raised immediately after it landed. According to our developer policy
this warrants immediate revert of the commit.

https://llvm.org/docs/DeveloperPolicy.html#patch-reversion-policy

Differential Revision: https://reviews.llvm.org/D155509

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Remove rdar links; NFC

This removes links to rdar, which is an internal bug tracker that the
community doesn't have visibility into.

See further discussion at:
https://discourse.llvm.org/t/code-rev

Remove rdar links; NFC

This removes links to rdar, which is an internal bug tracker that the
community doesn't have visibility into.

See further discussion at:
https://discourse.llvm.org/t/code-review-reminder-about-links-in-code-commit-messages/71847

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Revert "Remove -Wweak-template-vtables"

Turns out there's still some code referencing this. No harm in keeping it in a
bit longer.

> as it was planned for removal in clang 15 and we're now past the

Revert "Remove -Wweak-template-vtables"

Turns out there's still some code referencing this. No harm in keeping it in a
bit longer.

> as it was planned for removal in clang 15 and we're now past the branch point
>
> See https://github.com/llvm/llvm-project/issues/19107
>
> Differential revision: https://reviews.llvm.org/D118762

This reverts commit 564f9be11c9cb8d131f48df07538fab7a19b41a7.

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Remove -Wweak-template-vtables

as it was planned for removal in clang 15 and we're now past the branch point

See https://github.com/llvm/llvm-project/issues/19107

Differential revision: https://re

Remove -Wweak-template-vtables

as it was planned for removal in clang 15 and we're now past the branch point

See https://github.com/llvm/llvm-project/issues/19107

Differential revision: https://reviews.llvm.org/D118762

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Re-instate -Wweak-template-vtables as a no-op flag

Follow-up to 8c136805242014b6ad9ff1afcac9d7f4a18bec3f to allow a less
abrupt migration for users.

Differential revision: https://reviews.llvm.org/

Re-instate -Wweak-template-vtables as a no-op flag

Follow-up to 8c136805242014b6ad9ff1afcac9d7f4a18bec3f to allow a less
abrupt migration for users.

Differential revision: https://reviews.llvm.org/D112704

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PR18733: Remove -Wweak-template-vtables

It isn't really pulling its weight and I think splitting it out from
-Wweak-vtables was the wrong call: I think it was just a bug in the
original warning, whi

PR18733: Remove -Wweak-template-vtables

It isn't really pulling its weight and I think splitting it out from
-Wweak-vtables was the wrong call: I think it was just a bug in the
original warning, which was trying to not diagnose template
instantiations, implicit or explicit.

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Disable -Wweak-vtables when there are no key functions

Our -Wweak-vtables diagnostic is powered by our key function
calculation, which checks if key functions are enabled. We won't find
any key func

Disable -Wweak-vtables when there are no key functions

Our -Wweak-vtables diagnostic is powered by our key function
calculation, which checks if key functions are enabled. We won't find
any key functions in C++ ABIs that lack key functions, so -Wweak-vtables
was warning on every dynamic class before this change. So, turn off this
warning in ABIs without key functions.

Addresses PR31220

llvm-svn: 288850

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Don't let virtual calls and dynamic casts call Sema::MarkVTableUsed().

clang currently calls MarkVTableUsed() for classes that get their virtual
methods called or that participate in a dynamic_cast.

Don't let virtual calls and dynamic casts call Sema::MarkVTableUsed().

clang currently calls MarkVTableUsed() for classes that get their virtual
methods called or that participate in a dynamic_cast. This is unnecessary,
since CodeGen only emits vtables when it generates constructor, destructor, and
vtt code. (*)

Note that Sema::MarkVTableUsed() doesn't cause the emission of a vtable.
Its main user-visible effect is that it instantiates virtual member functions
of template classes, to make sure that if codegen decides to write a vtable
all the entries in the vtable are defined.

While this shouldn't change the behavior of codegen (other than being faster),
it does make clang more permissive: virtual methods of templates (in particular
destructors) end up being instantiated less often. In particular, classes that
have members that are smart pointers to incomplete types will now get their
implicit virtual destructor instantiated less frequently. For example, this
used to not compile but does now compile:

template <typename T> struct OwnPtr {
~OwnPtr() { static_assert((sizeof(T) > 0), "TypeMustBeComplete"); }
};
class ScriptLoader;
struct Base { virtual ~Base(); };
struct Sub : public Base {
virtual void someFun() const {}
OwnPtr<ScriptLoader> m_loader;
};
void f(Sub *s) { s->someFun(); }

The more permissive behavior matches both gcc (where this is not often
observable, since in practice most things with virtual methods have a key
function, and Sema::DefineUsedVTables() skips vtables for classes with key
functions) and cl (which is my motivation for this change) – this fixes
PR20337. See this issue and the review thread for some discussions about
optimizations.

This is similar to r213109 in spirit. r225761 was a prerequisite for this
change.

Various tests relied on "a->f()" marking a's vtable as used (in the sema
sense), switch these to just construct a on the stack. This forces
instantiation of the implicit constructor, which will mark the vtable as used.

(*) The exception is -fapple-kext mode: In this mode, qualified calls to
virtual functions (`a->Base::f()`) still go through the vtable, and since the
vtable pointer off this doesn't point to Base's vtable, this needs to reference
Base's vtable directly. To keep this working, keep referencing the vtable for
virtual calls in apple kext mode.

llvm-svn: 227073

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Remove the -cxx-abi command-line flag.

This makes the C++ ABI depend entirely on the target: MS ABI for -win32 triples,
Itanium otherwise. It's no longer possible to do weird combinations.

To be ab

Remove the -cxx-abi command-line flag.

This makes the C++ ABI depend entirely on the target: MS ABI for -win32 triples,
Itanium otherwise. It's no longer possible to do weird combinations.

To be able to run a test with a specific ABI without constraining it to a
specific triple, new substitutions are added to lit: %itanium_abi_triple and
%ms_abi_triple can be used to get the current target triple adjusted to the
desired ABI. For example, if the test suite is running with the i686-pc-win32
target, %itanium_abi_triple will expand to i686-pc-mingw32.

Differential Revision: http://llvm-reviews.chandlerc.com/D2545

llvm-svn: 199250

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Update tests in preparation for using the MS ABI for Win32 targets

In preparation for making the Win32 triple imply MS ABI mode,
make all tests pass in this mode, or make them use the Itanium
mode e

Update tests in preparation for using the MS ABI for Win32 targets

In preparation for making the Win32 triple imply MS ABI mode,
make all tests pass in this mode, or make them use the Itanium
mode explicitly.

Differential Revision: http://llvm-reviews.chandlerc.com/D2401

llvm-svn: 199130

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Provide a separate warning for weak vtables in explicit template instantiations. There's no (current) way to fix such templates to emit strong symbols/vtables, but perhaps users want to know about th

Provide a separate warning for weak vtables in explicit template instantiations. There's no (current) way to fix such templates to emit strong symbols/vtables, but perhaps users want to know about the cost being incurred anyway.

llvm-svn: 146265

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When checking for weak vtables, check whether the actual definition of
the key function is inline, rather than the original
declaration. Perhaps FunctionDecl::isInlined() is poorly named. Fixes
<rdar

When checking for weak vtables, check whether the actual definition of
the key function is inline, rather than the original
declaration. Perhaps FunctionDecl::isInlined() is poorly named. Fixes
<rdar://problem/9979458>.

llvm-svn: 140400

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Rework when and how vtables are emitted, by tracking where vtables are
"used" (e.g., we will refer to the vtable in the generated code) and
when they are defined (i.e., because we've seen the key fun

Rework when and how vtables are emitted, by tracking where vtables are
"used" (e.g., we will refer to the vtable in the generated code) and
when they are defined (i.e., because we've seen the key function
definition). Previously, we were effectively tracking "potential
definitions" rather than uses, so we were a bit too eager about emitting
vtables for classes without key functions.

The new scheme:
- For every use of a vtable, Sema calls MarkVTableUsed() to indicate
the use. For example, this occurs when calling a virtual member
function of the class, defining a constructor of that class type,
dynamic_cast'ing from that type to a derived class, casting
to/through a virtual base class, etc.
- For every definition of a vtable, Sema calls MarkVTableUsed() to
indicate the definition. This happens at the end of the translation
unit for classes whose key function has been defined (so we can
delay computation of the key function; see PR6564), and will also
occur with explicit template instantiation definitions.
- For every vtable defined/used, we mark all of the virtual member
functions of that vtable as defined/used, unless we know that the key
function is in another translation unit. This instantiates virtual
member functions when needed.
- At the end of the translation unit, Sema tells CodeGen (via the
ASTConsumer) which vtables must be defined (CodeGen will define
them) and which may be used (for which CodeGen will define the
vtables lazily).

From a language perspective, both the old and the new schemes are
permissible: we're allowed to instantiate virtual member functions
whenever we want per the standard. However, all other C++ compilers
were more lazy than we were, and our eagerness was both a performance
issue (we instantiated too much) and a portability problem (we broke
Boost test cases, which now pass).

Notes:
(1) There's a ton of churn in the tests, because the order in which
vtables get emitted to IR has changed. I've tried to isolate some of
the larger tests from these issues.
(2) Some diagnostics related to
implicitly-instantiated/implicitly-defined virtual member functions
have moved to the point of first use/definition. It's better this
way.
(3) I could use a review of the places where we MarkVTableUsed, to
see if I missed any place where the language effectively requires a
vtable.

Fixes PR7114 and PR6564.

llvm-svn: 103718

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rename llvm::llvm_report_error -> llvm::report_fatal_error

llvm-svn: 100708

Implement a warning diagnostic for weak vtables. Fixes PR6116.

llvm-svn: 95472