distinction between the different use-cases. With the previous default
behavior we would occasionally emit empty debug locations in situations
where they actually were strictly required (= on invoke insns).
We now have a choice between defaulting to an empty location or an
artificial location.
Specifically, this fixes a bug caused by a missing debug location when
emitting C++ EH cleanup blocks from within an artificial function, such as
an ObjC destroy helper function.
rdar://problem/19670595
llvm-svn: 228003
Currently we emit DeferredDeclsToEmit in reverse order. This patch changes that.
The advantages of the change are that
* The output order is a bit closer to the source order. The change to
test/CodeGenCXX/pod-member-memcpys.cpp is a good example.
* If we decide to deffer more, it will not cause as large changes in the
estcases as it would without this patch.
llvm-svn: 226751
Without setting the CurEHLocation these cleanups would be attributed to
whatever the last active debug line location was (the 'fn' call in the
included test cases). By setting CurEHLocation correctly the line
information is improved/corrected.
This quality bug turned into a crasher with r225000 when, instead of
allowing the last location to persist, it would be zero'd out. This
could lead to a function call (such as the dtor) being made without a
debug location - if that call was subsequently inlined (and the caller
and callee had debug info, just not the call instruction) the inliner
would violate important constraints about the debug location chains by
not updating the inlined instructions to chain up to the callee
locations.
So, by fixing this bug, I am addressing the assertion failures
introduced by r225000 and should be able to recommit that patch with
impunity...
llvm-svn: 225955
This was previously piggybacking on whatever happened to be the last
location set on CGDebugInfo/DIBuilder, which was wrong (it was often the
current location, such as the 'fn()' call site, not the end of the
block). With my improvements to set/unset the location in a scoped
manner (r225000) this went from a bad quality situation, to a crash.
Fixing this goes part-way to unblocking the recommit of r225000.
It's likely that any call to CodeGenFunction::StartFunction without the
CurEHLocation set represents a similar bug or risk of a bug. Perhaps
there are some callers that know they won't generate EH cleanups, but
I'm not sure.
I considered a generic catch-fix in StartFunction (just fallback to the
GlobalDecl's location) but that seemed like it'd mask bugs where the EH
location shouldn't be the same as the decl's location (& indeed by not
using that stop-gap I found this bug). We'll see how long I can hold out
on the generic catch-all. I might eventually be able to add an assertion
in.
llvm-svn: 225845
is for each machine. Fix up darwin tests that were testing for
aapcs on armv7-ios when the actual ABI is apcs.
Should be no user visible change without -cc1.
llvm-svn: 223429
Now that TailRecursionElimination has been fixed with r222354, the
threshold on size for lifetime marker insertion can be removed. This
only affects named temporary though, as the patch for unnamed temporaries
is still in progress.
llvm-svn: 222993
Avoid an assertion when materializing a lifetime type aggregate temporary. When
performing CodeGen for ObjC++, we could generate a lifetime-only aggregate
temporary by using an initializer list (which is effectively an array). We
would reach through the temporary expression, fishing out the inner expression.
If this expression was a lifetime expression, we would attempt to emit this as a
scalar. This would eventually result in an assertion as the emission would
eventually assert that the expression being emitted has a scalar evaluation
kind.
Add a case to handle the aggregate expressions. Use the EmitAggExpr to emit the
aggregate expression rather than the EmitScalarInit.
Addresses PR21347.
llvm-svn: 220590
CodeGenFunction objects aren't really designed to be reused for more
than one function, and doing so can leak debug info location information
from one function into the prologue of the next.
Add an assertion in to catch reuses of CodeGenFunction, which
surprisingly only caught the ObjC atomic getter/setter cases. Fix those
and add a test to demonstrate the issue.
The test is a bit slim, because we're just testing for the absence of a
debug location on the prologue instructions, which by itself probably
wouldn't be the end of the world - but the particular debug location
that was ending up there was for the previous function's last
instruction. This produced debug info for another function within this
function, which is something I'm trying to remove all cases of as its a
substantial source of bugs, especially around inlining (see r219215).
llvm-svn: 219690
Boostrapping LLVM+Clang+LLDB without threshold on object size for
lifetime markers insertion has shown there was no significant change
in compile time, so let the stack slot colorizer do its optimization
for all slots.
llvm-svn: 219303
If a base class declares a destructor, we will add the implicit
destructor for the subclass in
ActOnFields -> AddImplicitlyDeclaredMembersToClass
But in Objective C++, we did not compute whether we have a trivial
destructor until after that in
CXXRecordDecl::completeDefinition()
This was leading to a mismatch between the class, which thought it had
no trivial destructor, and the CXXDestructorDecl, which considered
itself trivial. It turns out the reason we delayed setting this until
completeDefinition() was for a warning that has since been removed as
part of -Warc-abi, so we just do it eagerly now.
llvm-svn: 218520
CXXNameMangler::mangleUnqualifiedBlock believed that
MangleContext::getBlockId returned something that used Itanium-style
discriminator numbers.
Discriminator numbers start their numberign from 1 and the first
mangling that actually gets any sort of number mangled in is the second
discriminator.
However, Block IDs start from zero. The logic for omitting the mangling
number did a ' > 1' instead of a ' > 0' comparison; this could
potentially cause mangling conflicts.
llvm-svn: 214699
Because references must be initialized using some evaluated expression, they
must point to something, and a callee can assume the reference parameter is
dereferenceable. Taking advantage of a new attribute just added to LLVM, mark
them as such.
Because dereferenceability in addrspace(0) implies nonnull in the backend, we
don't need both attributes. However, we need to know the size of the object to
use the dereferenceable attribute, so for incomplete types we still emit only
nonnull.
llvm-svn: 213386
This makes it easier to see where a global ctor comes from, and it also makes
ASan's init order analyzer output easier to understand. gcc does this too,
but only in -fPIC mode for some reason. Don't do this for constructors with
explicit init priority.
Also prepend "sub_" before the 'I', that way regular constructors stay
lexicographically after symbols with init priority (because
ord('s') > ord('I')). gold seems to ignore the name of constructor symbols,
and ld only looks at the symbol if it includes an init priority, which this
patch doesn't change.
Before: __GLOBAL_I_a
Now: __GLOBAL_sub_I_myfile.cc
llvm-svn: 208128
data members by addition of CXXDefaultInitExpr node to the initializer expression,
it has broken treatment of arc code for such initializations. Reviewed by John McCall.
// rdar://16299964
llvm-svn: 203935
In llvm the only semantic difference between internal and private is that llvm
tries to hide private globals my mangling them with a private prefix. Since
the globals changed by this patch already had the magic don't mangle marker,
there should be no change in the generated assembly.
A followup patch should then be able to drop the \01L and \01l prefixes and let
llvm mangle as appropriate.
llvm-svn: 202419
unique them and permits the implementation of dynamic_cast (and
anything else which knows it's working with a complete class
type) to compare their addresses directly.
rdar://16005328
llvm-svn: 201020
When a non-trivial parameter is present, clang now gathers up all the
parameters that lack inreg and puts them into a packed struct. MSVC
always aligns each parameter to 4 bytes and no more, so this is a pretty
simple struct to lay out.
On win64, non-trivial records are passed indirectly. Prior to this
change, clang was incorrectly using byval on win64.
I'm able to self-host a working clang with this change and additional
LLVM patches.
Reviewers: rsmith
Differential Revision: http://llvm-reviews.chandlerc.com/D2636
llvm-svn: 200597
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
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
Summary:
MSVC destroys arguments in the callee from left to right. Because C++
objects have to be destroyed in the reverse order of construction, Clang
has to construct arguments from right to left and destroy arguments from
left to right.
This patch fixes the ordering by reversing the order of evaluation of
all call arguments under the MS C++ ABI.
Fixes PR18035.
Reviewers: rsmith
Differential Revision: http://llvm-reviews.chandlerc.com/D2275
llvm-svn: 196402
Specifically, handle the case where the block is in a default argument
in a class method. The mangling here follows what we do for lambdas.
llvm-svn: 185991
Make sure we properly treat names defined inside a block as local
names. There are basically three fixes here. One, correctly
treat blocks as a context where we need to use local-name mangling using
the new isLocalContainerContext helper. Two, make
CXXNameMangler::manglePrefix handle local names in a consistent way.
Three, extend CXXNameMangler::mangleLocalName so it can mangle a block
correctly.
llvm-svn: 185450
Blocks, like lambdas, can be written in contexts which are required to be
treated as the same under ODR. Unlike lambdas, it isn't possible to actually
take the address of a block, so the mangling of the block itself doesn't
matter. However, objects like static variables inside a block do need to
be mangled in a consistent way.
There are basically three components here. One, block literals need a
consistent numbering. Two, objects/types inside a block literal need
to be mangled using it. Three, objects/types inside a block literal need
to have their linkage computed correctly.
llvm-svn: 185372
This changes the mangling of local static variables/etc. inside blocks
to do something simple and sane. This avoids depending on the way we mangle
blocks, which isn't really appropriate here.
John, please take a look at this to make sure the mangling I chose is sane.
Fixes <rdar://problem/14074423>.
llvm-svn: 184780
to provide proper overloading, and also prevents mangling conflicts with
template arguments of protocol-qualified type.
This is a non-backward-compatible mangling change, but per discussion with
John, the benefits outweigh this cost.
Fixes <rdar://problem/14074822>.
llvm-svn: 184250
a lambda.
Bug #1 is that CGF's CurFuncDecl was "stuck" at lambda invocation
functions. Fix that by generally improving getNonClosureContext
to look through lambdas and captured statements but only report
code contexts, which is generally what's wanted. Audit uses of
CurFuncDecl and getNonClosureAncestor for correctness.
Bug #2 is that lambdas weren't specially mapping 'self' when inside
an ObjC method. Fix that by removing the requirement for that
and using the normal EmitDeclRefLValue path in LoadObjCSelf.
rdar://13800041
llvm-svn: 181000
It's a kind of implicit conversion, which we generally drop, but
more importantly it's got very specific placement requirements.
rdar://13617051
llvm-svn: 179254
a normal cleanup when entering a @try or @synchronized to
ensure that we clean that up if an exception is triggered.
Apparently GCC did this, so it's hard to argue that we shouldn't
do at least as much.
rdar://12364847
llvm-svn: 178599
to an out-parameter using the indirect-writeback conversion,
and we copied the current value of the variable to the temporary,
make sure that we register an intrinsic use of that value with
the optimizer so that the value won't get released until we have
a chance to retain it.
rdar://13195034
llvm-svn: 177813
This was causing correctness issues for ARC and the static analyzer when a
function template has "consumed" Objective-C object parameters (i.e.
parameters that will be released by the function before returning).
The fix is threefold:
(1) Actually copy over the attributes from old ParmVarDecls to new ones.
(2) Have Sema::BuildFunctionType only work for building FunctionProtoTypes,
which it was doing anyway. This allows us to pass an ExtProtoInfo
instead of a plain ExtInfo and several flags.
(3) Drop param attributes as part of StripImplicitInstantiation, which is
used when an implicit instantiation is followed by an explicit one.
<rdar://problem/12685622>
llvm-svn: 176728
whether we already have a method. Fixes a bug where we were
failing to properly contextually convert a message receiver
during template instantiation.
As a side-effect, we now actually perform correct method lookup
after adjusting a message-send to integral or non-ObjC pointer
types (legal outside of ARC).
rdar://13305374
llvm-svn: 176339
These are two related changes (one in llvm, one in clang).
LLVM:
- rename address_safety => sanitize_address (the enum value is the same, so we preserve binary compatibility with old bitcode)
- rename thread_safety => sanitize_thread
- rename no_uninitialized_checks -> sanitize_memory
CLANG:
- add __attribute__((no_sanitize_address)) as a synonym for __attribute__((no_address_safety_analysis))
- add __attribute__((no_sanitize_thread))
- add __attribute__((no_sanitize_memory))
for S in address thread memory
If -fsanitize=S is present and __attribute__((no_sanitize_S)) is not
set llvm attribute sanitize_S
llvm-svn: 176076
arguments in function prologue is done
with objc_StoreStrong to pair it with
similar objc_StoreStrong for release in function
epilogue. This is done with -O0 only.
// rdar://13145317
llvm-svn: 175698
We were previously hard-coding a particular field index. This was
fine before (because we were obviously guaranteed the presence
of a copy/dispose member) except for (1) alignment padding and
(2) future extensions adding extra members to the header, such
as the extended-layout pointer.
Note that we only introduce the extended-layout pointer in the
presence of structs. (We also seem to be introducing it even
in the presence of an all-non-object layout, but that's a
different potential issue.)
llvm-svn: 173122
objc_loadWeak. This retains and autorelease the weakly-refereced
object. This hidden autorelease sometimes makes __weak variable alive even
after the weak reference is erased, because the object is still referenced
by an autorelease pool. This patch overcomes this behavior by loading a
weak object via call to objc_loadWeakRetained(), followng it by objc_release
at appropriate place, thereby removing the hidden autorelease. // rdar://10849570
llvm-svn: 168740
if the type of the value is a non-trivial class type. Fixes PR14318.
(There's a minor ObjC++ language change here: given that we can't save the
value, the type of the assignment expression is void in such cases.)
llvm-svn: 167884
checks to enable. Remove frontend support for -fcatch-undefined-behavior,
-faddress-sanitizer and -fthread-sanitizer now that they don't do anything.
llvm-svn: 167413
extern "C", its method definitions must be IRGen'ed
before meta-data for class is generated. Otherwise,
IRGen crashes (to say the least).
// rdar://12581683
llvm-svn: 166809
combination of a load+objc_release; this is generally better
for tools that try to track why values are retained and
released. Also use objc_storeStrong when copying a block
(again, only at -O0), which requires us to do a preliminary
store of null in order to compensate for objc_storeStrong's
assign semantics.
llvm-svn: 166085
to overwrite objects that might have been allocated into the type's
tail padding. This patch is missing some potential optimizations where
the destination is provably a complete object, but it's necessary for
correctness.
Patch by Jonathan Sauer.
llvm-svn: 162254
was mistakenly classifying dynamic_casts which might throw as having no side
effects.
Switch it from a visitor to a switch, so it is kept up-to-date as future Expr
nodes are added. Move it from ExprConstant.cpp to Expr.cpp, since it's not
really related to constant expression evaluation.
Since we use HasSideEffect to determine whether to emit an unused global with
internal linkage, this has the effect of suppressing emission of globals in
some cases.
I've left many of the Objective-C cases conservatively assuming that the
expression has side-effects. I'll leave it to someone with better knowledge
of Objective-C than mine to improve them.
llvm-svn: 161388
literal helper functions. All helper functions (global
and locals) use block_invoke as their prefix. Local literal
helper names are prefixed by their enclosing mangled function
names. Blocks in non-local initializers (e.g. a global variable
or a C++11 field) are prefixed by their mangled variable name.
The descriminator number added to end of the name starts off
with blank (for first block) and _<N> (for the N+2-th block).
llvm-svn: 159206
target Objective-C runtime down to the frontend: break this
down into a single target runtime kind and version, and compute
all the relevant information from that. This makes it
relatively painless to add support for new runtimes to the
compiler. Make the new -cc1 flag, -fobjc-runtime=blah-x.y.z,
available at the driver level as a better and more general
alternative to -fgnu-runtime and -fnext-runtime. This new
concept of an Objective-C runtime also encompasses what we
were previously separating out as the "Objective-C ABI", so
fragile vs. non-fragile runtimes are now really modelled as
different kinds of runtime, paving the way for better overall
differentiation.
As a sort of special case, continue to accept the -cc1 flag
-fobjc-runtime-has-weak, as a sop to PLCompatibilityWeak.
I won't go so far as to say "no functionality change", even
ignoring the new driver flag, but subtle changes in driver
semantics are almost certainly not intended.
llvm-svn: 158793
the template instantiation of statement-expressions.
I think it was jyasskin who had a crashing testcase in this area;
hopefully this fixes it and he can find his testcase and check it in.
llvm-svn: 154189
NSNumber, and boolean literals. This includes both Sema and Codegen support.
Included is also support for new Objective-C container subscripting.
My apologies for the large patch. It was very difficult to break apart.
The patch introduces changes to the driver as well to cause clang to link
in additional runtime support when needed to support the new language features.
Docs are forthcoming to document the implementation and behavior of these features.
llvm-svn: 152137
Note that this transformation has a substantial semantic effect outside of ARC: it gives the converted lambda lifetime semantics similar to a block literal. With ARC, the effect is much less obvious because the lifetime of blocks is already managed.
llvm-svn: 151797
attribute into CodeGenModule::SetLLVMFunctionAttributesForDefinition().
Previously it resided in CodeGenModule::GetOrCreateLLVMFunction, which
for some reason wasn't called for ObjC class methods, see
http://code.google.com/p/address-sanitizer/issues/detail?id=33
llvm-svn: 149605
c++ object reference type with trivial copy constructor.
This causes an assert crash and bad code gen. when assert
is off. // rdar://6137845
llvm-svn: 147573
template instantiation), and that expression might produce a
temporary, invoke MaybeBindToTemporary. Otherwise, we forget to
destroy objects, release objects, etc. Fixes <rdar://problem/10531073>.
llvm-svn: 146301
really bad way to go about this, but I'm not sure there's a better
choice without substantial changes to TreeTransform --- most
notably, preserving implicit semantic nodes instead of discarding
and rebuilding them.
llvm-svn: 145480
We'd also like for "C++11" or "c++11" to be used for the warning
groups, but without removing the old warning flags. Patches welcome;
I've run out of time to work on this today.
llvm-svn: 141801
increasingly prevailing case to the point that new features
like ARC don't even support the fragile ABI anymore.
This required a little bit of reshuffling with exceptions
because a check was assuming that ObjCNonFragileABI was
only being set in ObjC mode, and that's actually a bit
obnoxious to do.
Most, though, it involved a perl script to translate a ton
of test cases.
Mostly no functionality change for driver users, although
there are corner cases with disabling language-specific
exceptions that we should handle more correctly now.
llvm-svn: 140957
This model uses the 'landingpad' instruction, which is pinned to the top of the
landing pad. (A landing pad is defined as the destination of the unwind branch
of an invoke instruction.) All of the information needed to generate the correct
exception handling metadata during code generation is encoded into the
landingpad instruction.
The new 'resume' instruction takes the place of the llvm.eh.resume intrinsic
call. It's lowered in much the same way as the intrinsic is.
llvm-svn: 140049
__block variables where the act of initialization/assignment
itself causes the __block variable to be copied to the heap
because the variable is of block type and is being assigned
a block literal which captures the variable.
rdar://problem/9814099
llvm-svn: 136337
for-in statements; specifically, make sure to close over any
temporaries or cleanups it might require. In ARC, this has
implications for the lifetime of the collection, so emit it
with a retain and release it upon exit from the loop.
rdar://problem/9817306
llvm-svn: 136204
This is something of a hack, the problem is as follows:
1. we instantiate both copied of RetainPtr with the two different argument types
(an id and protocol-qualified id).
2. We refer to the ctor of one of the instantiations when introducing global "x",
this causes us to emit an llvm::Function for a prototype whose "this" has type
"RetainPtr<id<bork> >*".
3. We refer to the ctor of the other instantiation when introducing global "y",
however, because it *mangles to the same name as the other ctor* we just use
a bitcasted version of the llvm::Function we previously emitted.
4. We emit deferred declarations, causing us to emit the body of the ctor, however
the body we emit is for RetainPtr<id>, which expects its 'this' to have an IR
type of "RetainPtr<id>*".
Because of the mangling collision, we don't have this case, and explode.
This is really some sort of weird AST invariant violation or something, but hey
a bitcast makes the pain go away.
llvm-svn: 135572
conservative when converting a functiontype to IR when in a "pointer within
a struct" context. This has the unfortunate sideeffect of compiling all
function pointers inside of structs into "{}*" which, though correct, is
ugly. This has the positive side effect of being correct, and it is pretty
straight-forward to improve on this.
llvm-svn: 134861
where we have an immediate need of a retained value.
As an exception, don't do this when the call is made as the immediate
operand of a __bridge retain. This is more in the way of a workaround
than an actual guarantee, so it's acceptable to be brittle here.
rdar://problem/9504800
llvm-svn: 134605
structure to hold inferred information, then propagate each invididual
bit down to -cc1. Separate the bits of "supports weak" and "has a native
ARC runtime"; make the latter a CodeGenOption.
The tool chain is still driving this decision, because it's the place that
has the required deployment target information on Darwin, but at least it's
better-factored now.
llvm-svn: 134453
objects, so that we steal the retain count of a temporary __strong
pointer (zeroing out that temporary), eliding a retain/release
pair. Addresses <rdar://problem/9364932>.
llvm-svn: 133621
retain/release the temporary object appropriately. Previously, we
would only perform the retain/release operations when the reference
would extend the lifetime of the temporary, but this does the wrong
thing across calls.
llvm-svn: 133620
qualifiers, so that an __unsafe_unretained-qualified type T in ARC code
will have the same mangling as T in non-ARC code, improving ABI
interoperability. This works now because we infer or require a
lifetime qualifier everywhere one can appear in an external
interface. Another part of <rdar://problem/9595486>.
llvm-svn: 133306
Language-design credit goes to a lot of people, but I particularly want
to single out Blaine Garst and Patrick Beard for their contributions.
Compiler implementation credit goes to Argyrios, Doug, Fariborz, and myself,
in no particular order.
llvm-svn: 133103
with a type-dependent expression, infer the placeholder type
'Context.DependentTy' to indicate that this is just a
placeholder. Fixes PR9982 / <rdar://problem/9486685>.
llvm-svn: 132657
Go through and expand the members of bases into the encoding string (and encode the VTable as well).
Unlike gcc which expands virtual bases as many times as they appear in the
hierarchy, clang will only expand them once at the end, to reflect the actual layout.
Note that there doesn't seem to be a way to indicate in the encoding that
packing/alignment of members is different that normal, in which case
the encoding will be out-of-sync with the real layout.
If the runtime switches to just consider the size of types without
taking into account alignment, we could easily make padding explicit in the
encoding (e.g. using arrays of chars). The encoding strings would be
longer then though.
Also encode a flexible array member as array of 0 size, like gcc, not as a pointer.
llvm-svn: 131365
The prototype for objc_msgSend() is technically variadic -
`id objc_msgSend(id, SEL, ...)`.
But all method calls should use a prototype that matches the method,
not the prototype for objc_msgSend itself().
// rdar://9048030
llvm-svn: 126678
- BlockDeclRefExprs always store VarDecls
- BDREs no longer store copy expressions
- BlockDecls now store a list of captured variables, information about
how they're captured, and a copy expression if necessary
With that in hand, change IR generation to use the captures data in
blocks instead of walking the block independently.
Additionally, optimize block layout by emitting fields in descending
alignment order, with a heuristic for filling in words when alignment
of the end of the block header is insufficient for the most aligned
field.
llvm-svn: 125005
not actually frequently used, because ImpCastExprToType only creates a node
if the types differ. So explicitly create an ICE in the lvalue-to-rvalue
conversion code in DefaultFunctionArrayLvalueConversion() as well as several
other new places, and consistently deal with the consequences throughout the
compiler.
In addition, introduce a new cast kind for loading an ObjCProperty l-value,
and make sure we emit those nodes whenever an ObjCProperty l-value appears
that's not on the LHS of an assignment operator.
This breaks a couple of rewriter tests, which I've x-failed until future
development occurs on the rewriter.
Ted Kremenek kindly contributed the analyzer workarounds in this patch.
llvm-svn: 120890
follows objective's semantics and is not overload'able
with an assignment operator. Fixes a crash and a missing
diagnostics. Radar 8379892.
llvm-svn: 113555
a -cc1 option. The Darwin linker complains about mixed visibility when linking
gcc-built objects with clang-built objects, and the optimization isn't really
that valuable. Platforms with less ornery linkers can feel free to enable this.
llvm-svn: 110979
an lvalue of another, compatible Objective-C object type (e.g., a
subclass). Introduce a new initialization sequence step kind to
describe this binding, along with a new cast kind. Fixes PR7741.
llvm-svn: 110513
Flag synthesized struct decl. as non-empty so
CXX side of ir gen does not skip its Null initialization.
Fixes radar 8027844 for objc++'s collection statement.
llvm-svn: 104837