Commit Graph

97 Commits

Author SHA1 Message Date
Adrian Prantl
d6a9bbf68e Replace auto -> llvm::Optional<uint64_t>
This addresses post-commit feedback for https://reviews.llvm.org/D56688

llvm-svn: 351237
2019-01-15 20:33:58 +00:00
Adrian Prantl
d963a7c398 Make CompilerType::getBitSize() / getByteSize() return an optional result. NFC
The code in LLDB assumes that CompilerType and friends use the size 0
as a sentinel value to signal an error. This works for C++, where no
zero-sized type exists, but in many other programming languages
(including I believe C) types of size zero are possible and even
common. This is a particular pain point in swift-lldb, where extra
code exists to double-check that a type is *really* of size zero and
not an error at various locations.

To remedy this situation, this patch starts by converting
CompilerType::getBitSize() and getByteSize() to return an optional
result. To avoid wasting space, I hand-rolled my own optional data
type assuming that no type is larger than what fits into 63
bits. Follow-up patches would make similar changes to the ValueObject
hierarchy.

rdar://problem/47178964

Differential Revision: https://reviews.llvm.org/D56688

llvm-svn: 351214
2019-01-15 18:07:52 +00:00
Zachary Turner
863f8c18b9 [SymbolFile] Make ParseCompileUnitXXX accept a CompileUnit&.
Previously all of these functions accepted a SymbolContext&.
While a CompileUnit is one member of a SymbolContext, there
are also many others, and by passing such a monolithic parameter
in this way it makes the requirements and assumptions of the
API unclear for both callers as well as implementors.

All these methods need is a CompileUnit.  By limiting the
parameter type in this way, we simplify the code as well as
make it self-documenting for both implementers and users.

Differential Revision: https://reviews.llvm.org/D56564

llvm-svn: 350943
2019-01-11 18:03:20 +00:00
Adrian Prantl
6ea33bc19b Convert to LLDB coding style (NFC)
llvm-svn: 350651
2019-01-08 20:48:40 +00:00
Adrian Prantl
c5e0c58875 Simplify code.
llvm-svn: 350577
2019-01-07 23:08:16 +00:00
Adrian Prantl
511d7d1fc1 Clarify comment and variable names. (NFC)
llvm-svn: 350576
2019-01-07 23:02:28 +00:00
Adrian Prantl
95280c948d Rename DWARFDIE::GetDWOContext() -> GetDeclContext() (NFC)
Despite the name, this function has nothing to do with the DWO format.

llvm-svn: 350575
2019-01-07 22:47:17 +00:00
Jonas Devlieghere
a6682a413d Simplify Boolean expressions
This patch simplifies boolean expressions acorss LLDB. It was generated
using clang-tidy with the following command:

run-clang-tidy.py -checks='-*,readability-simplify-boolean-expr' -format -fix $PWD

Differential revision: https://reviews.llvm.org/D55584

llvm-svn: 349215
2018-12-15 00:15:33 +00:00
Zachary Turner
6753d2d180 [ast] CreateParameterDeclaration should use an appropriate DeclContext.
Previously CreateParameterDeclaration was always using the translation
unit DeclContext.  We would later go and add parameters to the
FunctionDecl, but internally clang makes a copy when you do this, and
we'd end up with ParmVarDecl's at the global scope as well as in the
function scope.

This fixes the issue.  It's hard to say whether this will introduce
a behavioral change in name lookup, but I know there have been several
hacks introduced in previous years to deal with collisions between
various types of variables, so there's a chance that this patch could
obviate one of those hacks.

Differential Revision: https://reviews.llvm.org/D55571

llvm-svn: 348941
2018-12-12 17:17:53 +00:00
Shafik Yaghmour
8c5ec1ff46 Refactor ClangASTContext::AddEnumerationValueToEnumerationType() to remove redundant parameter which can be calculated from other parameter.
rdar://problem/43822994

Differential Revision: https://reviews.llvm.org/D54003

llvm-svn: 346428
2018-11-08 18:42:00 +00:00
Adrian Prantl
eca07c592a Fix (and improve) the support for C99 variable length array types
Clang recently improved its DWARF support for C VLA types. The DWARF
now looks like this:

0x00000051:         DW_TAG_variable [4]
                     DW_AT_location( fbreg -32 )
                     DW_AT_name( "__vla_expr" )
                     DW_AT_type( {0x000000d3} ( long unsigned int ) )
                     DW_AT_artificial( true )
...
0x000000da:     DW_TAG_array_type [10] *
                 DW_AT_type( {0x000000cc} ( int ) )

0x000000df:         DW_TAG_subrange_type [11]
                     DW_AT_type( {0x000000e9} ( __ARRAY_SIZE_TYPE__ ) )
                     DW_AT_count( {0x00000051} )

Without this patch LLDB will naively interpret the DIE offset 0x51 as
the static size of the array, which is clearly wrong.  This patch
extends ValueObject::GetNumChildren to query the dynamic properties of
incomplete array types.

See the testcase for an example:

   4   int foo(int a) {
   5   	     int vla[a];
   6   	       for (int i = 0; i < a; ++i)
   7   	           vla[i] = i;
   8
-> 9            pause(); // break here
   10  		return vla[a-1];
   11   }

(lldb) fr v vla
(int []) vla = ([0] = 0, [1] = 1, [2] = 2, [3] = 3)
(lldb) quit

rdar://problem/21814005

Differential Revision: https://reviews.llvm.org/D53530

llvm-svn: 346165
2018-11-05 20:49:07 +00:00
Zachary Turner
970f38ead6 [NFC] Refactor SetBaseClasses and DeleteBaseClasses.
We currently had a 2-step process where we had to call
SetBaseClassesForType and DeleteBaseClasses.  Every single caller
followed this exact 2-step process, and there was manual memory
management going on with raw pointers.  We can do better than this
by storing a vector of unique_ptrs and passing this around.
This makes for a cleaner API, and we only need to call one method
so there is no possibility of a user forgetting to call
DeleteBaseClassSpecifiers.

In addition to this, it also makes for a *simpler* API.  Part of
why I wanted to do this is because when I was implementing the native
PDB interface I had to spend some time understanding exactly what I
was deleting and why.  ClangAST has significant mental overhead
associated with it, and reducing the API surface can go along
way to making it simpler for people to understand.

Differential Revision: https://reviews.llvm.org/D53590

llvm-svn: 345312
2018-10-25 20:44:56 +00:00
Zachary Turner
a3e2ea1c4a Change two methods from const char* to StringRef [NFC].
llvm-svn: 345055
2018-10-23 17:22:02 +00:00
Aleksandr Urakov
7d2a74fc54 [PDB] Parse UDT symbols and pointers to members (combined patch)
Summary:
In this patch I've tried to combine the best ideas from D49368 and D49410,
so it implements following:

- Completion of UDTs from a PDB with a filling of a layout info;
- Pointers to members;
- Fixes the bug relating to a virtual base offset reading from `vbtable`.
  The offset was treated as an unsigned, but it can be a negative sometimes.
- Support of MSInheritance attribute

Reviewers: asmith, zturner, rnk, labath, clayborg, lldb-commits

Reviewed By: zturner

Subscribers: aleksandr.urakov, stella.stamenova, JDevlieghere, lldb-commits

Differential Revision: https://reviews.llvm.org/D49980

llvm-svn: 339649
2018-08-14 07:57:44 +00:00
Davide Italiano
6699fc34dd [DWARFASTParser] Remove special cases for llvm-gcc
Reviewed by: aprantl, labath.

Differential Revision:  https://reviews.llvm.org/D48500

llvm-svn: 338638
2018-08-01 21:13:45 +00:00
Frederic Riss
adc94a8846 Remove dead code
Our DWARF parsing code had a workaorund for Objective-C "self" not
being marked as artifial by the compiler. Clang has been doing this
since 2010, so let's just drop the workaround.

llvm-svn: 335313
2018-06-22 00:22:50 +00:00
Adrian Prantl
4e8be2c98e Fix/unify the spelling of Objective-C.
llvm-svn: 334614
2018-06-13 16:21:24 +00:00
Greg Clayton
f56c30d13b General cleanup to minimize the .debug_types patch
This cleanup is designed to make the https://reviews.llvm.org/D32167 patch smaller and easier to read.

Cleanup in this patch:

Allow DWARFUnit subclasses to hand out the data that should be used when decoding data for a DIE. The information might be in .debug_info or could be in .debug_types. There is a new virtual function on DWARFUnit that each subclass must override:

virtual const lldb_private::DWARFDataExtractor &DWARFUnit::GetData() const;
This allows DWARFCompileUnit and eventually DWARFTypeUnit to hand out different data to be used when decoding the DIE information.

Add a new pure virtual function to get the size of the DWARF unit header:

virtual uint32_t DWARFUnit::GetHeaderByteSize() const = 0;
This allows DWARFCompileUnit and eventually DWARFTypeUnit to hand out different offsets where the first DIE starts when decoding DIE information from the unit.

Added a new function to DWARFDataExtractor to get the size of an offset:

size_t DWARFDataExtractor::GetDWARFSizeOfOffset() const;
Removed dead dumping and parsing code in the DWARFDebugInfo class.
Inlined a bunch of calls in DWARFUnit for accessors that were just returning integer member variables.
Renamed DWARFUnit::Size() to DWARFUnit::GetHeaderByteSize() as it clearly states what it is doing and makes more sense.

Differential Revision: https://reviews.llvm.org/D46606

llvm-svn: 331892
2018-05-09 16:42:53 +00:00
Adrian Prantl
05097246f3 Reflow paragraphs in comments.
This is intended as a clean up after the big clang-format commit
(r280751), which unfortunately resulted in many of the comment
paragraphs in LLDB being very hard to read.

FYI, the script I used was:

import textwrap
import commands
import os
import sys
import re
tmp = "%s.tmp"%sys.argv[1]
out = open(tmp, "w+")
with open(sys.argv[1], "r") as f:
  header = ""
  text = ""
  comment = re.compile(r'^( *//) ([^ ].*)$')
  special = re.compile(r'^((([A-Z]+[: ])|([0-9]+ )).*)|(.*;)$')
  for line in f:
      match = comment.match(line)
      if match and not special.match(match.group(2)):
          # skip intentionally short comments.
          if not text and len(match.group(2)) < 40:
              out.write(line)
              continue

          if text:
              text += " " + match.group(2)
          else:
              header = match.group(1)
              text = match.group(2)

          continue

      if text:
          filled = textwrap.wrap(text, width=(78-len(header)),
                                 break_long_words=False)
          for l in filled:
              out.write(header+" "+l+'\n')
              text = ""

      out.write(line)

os.rename(tmp, sys.argv[1])

Differential Revision: https://reviews.llvm.org/D46144

llvm-svn: 331197
2018-04-30 16:49:04 +00:00
Jan Kratochvil
55c84b1a4e Match also DW_TAG_partial_unit when DW_TAG_compile_unit is matched
Code commonly checks if the parent DIE is DW_TAG_compile_unit.
But DW_TAG_partial_unit also acts as DW_TAG_compile_unit for DWZ
as DWZ is using DW_TAG_imported_unit only at the top unit level.

Differential revision: https://reviews.llvm.org/D40469

llvm-svn: 331194
2018-04-30 16:04:32 +00:00
Adrian Prantl
690c828b0b Fix a crash when resolving overloads of C++ virtual methods.
The isOverload() method needs to account for situations where the two
methods being compared don't have the same number of arguments.

rdar://problem/39542960

llvm-svn: 330450
2018-04-20 17:14:05 +00:00
Davide Italiano
981ec1d199 [DWARFASTParserClang] Remove dead code. NFCI.
llvm-svn: 330385
2018-04-20 00:44:33 +00:00
Frederic Riss
f4e7e5210c Support template template parameters
Summary:
We would fail to resolve (and thus display the value of) any
templated type which contained a template template argument even
though we don't really use template arguments.

This patch adds minimal support for template template arguments,
but I doubt we need any more than that.

Reviewers: clayborg, jingham

Subscribers: JDevlieghere, lldb-commits

Differential Revision: https://reviews.llvm.org/D44613

llvm-svn: 328984
2018-04-02 16:18:32 +00:00
Davide Italiano
675767a591 Use the DWARF linkage name when importing C++ methods.
When importing C++ methods into clang AST nodes from the DWARF symbol
table, preserve the DW_AT_linkage_name and use it as the linker
("asm") name for the symbol.

Concretely, this enables `expression` to call into names that use the
GNU `abi_tag` extension, and enables lldb to call into code using
std::string or std::list from recent versions of libstdc++. See
https://bugs.llvm.org/show_bug.cgi?id=35310 . It also seems broadly
more robust than relying on the DWARF->clang->codegen pipeline to
roundtrip properly, but I'm not immediately aware of any other cases
in which it makes a difference.

Patch by Nelson Elhage!

Differential Revision:  https://reviews.llvm.org/D40283

llvm-svn: 328658
2018-03-27 19:40:50 +00:00
Jim Ingham
df9f50d23c Add support for __attribute__(trivial_abi).
<rdar://problem/36035075>, <rdar://problem/36035039>

llvm-svn: 328389
2018-03-23 23:44:52 +00:00
Frederic Riss
b6073eb6e1 Fix the Windows build after r327750
llvm-svn: 327753
2018-03-16 22:19:58 +00:00
Frederic Riss
cce4af160c [DWARFASTParserClang] Complete external record types before using them as a decl context.
Summary:
When in a gmodules-like debugging scenario, you can have a parent decl context
that gets imported from an external AST. When this happens, we must be careful
to complete this type before adding children to it, otherwise it sometimes
results in a crash.

Reviewers: clayborg, jingham

Subscribers: aprantl, JDevlieghere, lldb-commits

Differential Revision: https://reviews.llvm.org/D43592

llvm-svn: 327750
2018-03-16 22:12:22 +00:00
Jan Kratochvil
50397237d9 refactor: DWARFCompileUnit::Producer -> DWARFProducer
Differential revision: https://reviews.llvm.org/D42891

llvm-svn: 324275
2018-02-05 21:50:01 +00:00
Jim Ingham
1765028d3c Remove unused Args variable, and #include of Args.h. NFC.
llvm-svn: 324008
2018-02-01 21:31:14 +00:00
Lang Hames
48b32f4ced [lldb] Fix some C++ virtual method call bugs in LLDB expression evaluation by
building method override tables for CXXMethodDecls in 
DWARFASTParserClang::CompleteTypeFromDWARF.

C++ virtual method calls in LLDB expressions may fail if the override table for
the method being called is not correct as IRGen will produce references to the
wrong (or a missing) vtable entry.

This patch does not fix calls to virtual methods with covariant return types as
it mistakenly treats these as overloads, rather than overrides. This will be
addressed in a future patch.

Review: https://reviews.llvm.org/D41997

Partially fixes <rdar://problem/14205774>

llvm-svn: 323163
2018-01-22 23:53:56 +00:00
Adrian Prantl
dce4a9aa59 Look for external types in all clang modules imported by the current symbol file.
This fixes a bug in -gmodules DWARF handling when debugging without a .dSYM bundle
that was particularly noticable when debugging LLVM itself.

Debugging without clang modules and DWO handling should be unaffected by this patch.

<rdar://problem/32436209>

llvm-svn: 321802
2018-01-04 16:42:05 +00:00
Adrian Prantl
559d2c98a8 Bring clang options in error messages up to date.
llvm-svn: 321322
2017-12-21 23:04:51 +00:00
Jim Ingham
4e29eed498 ClangASTContext::ParseClassTemplateDecl doesn't always succeed.
When it does, it returns a NULL ClassTemplateDecl.  Don't use 
it if it is NULL...

<rdar://problem/35672107>

llvm-svn: 319516
2017-12-01 03:41:30 +00:00
Tamas Berghammer
5976583a30 Support scoped enums in the DWARF AST parser
Subscribers: JDevlieghere

Differential Revision: https://reviews.llvm.org/D39545

llvm-svn: 317563
2017-11-07 10:39:22 +00:00
Tamas Berghammer
bba2c83493 Remove the DWARFExpression -> Clang ExpressionParser dependency
It was completly unused and broke the part of the encapsulation that
common code shouldn't depend on specific plugins or language specific
features.

llvm-svn: 311000
2017-08-16 11:45:10 +00:00
Pavel Labath
32f29fac41 Fix assorted compiler warnings. NFC
llvm-svn: 304796
2017-06-06 14:06:22 +00:00
Sean Callanan
09e91ac6ab [DWARF parser] Produce correct template parameter packs
Templates can end in parameter packs, like this

template <class T...> struct MyStruct 
  { /*...*/ };

LLDB does not currently support these parameter packs; 
it does not emit them into the template argument list
at all. This causes problems when you specialize, e.g.:

template <> struct MyStruct<int> 
  { /*...*/ };
template <> struct MyStruct<int, int> : MyStruct<int> 
  { /*...*/ };

LLDB generates two template specializations, each with 
no template arguments, and then when they are imported 
by the ASTImporter into a parser's AST context we get a 
single specialization that inherits from itself, 
causing Clang's record layout mechanism to smash its
stack.

This patch fixes the problem for classes and adds
tests. The tests for functions fail because Clang's
ASTImporter can't import them at the moment, so I've
xfailed that test.

Differential Revision: https://reviews.llvm.org/D33025

llvm-svn: 302833
2017-05-11 22:08:05 +00:00
Pavel Labath
4d35d6b3b3 Change UniqueCStringMap to use ConstString as the key
Summary:
UniqueCStringMap "sorts" the entries for fast lookup, but really it only cares about uniqueness.  ConstString can be compared by pointer alone, rather than with strcmp, resulting in much faster comparisons.  Change the interface to take ConstString instead, and propagate use of the type to the callers where appropriate.

Reviewers: #lldb, clayborg

Reviewed By: clayborg

Subscribers: labath, jasonmolenda, lldb-commits

Differential Revision: https://reviews.llvm.org/D32316
Patch by Scott Smith <scott.smith@purestorage.com>.

llvm-svn: 301908
2017-05-02 10:17:30 +00:00
Sean Callanan
b494578afb [DWARF] Fix lookup in the abstract origins of inlined blocks/functions
LLDB uses clang::DeclContexts for lookups, and variables get put into
the DeclContext for their abstract origin. (The abstract origin is a 
DWARF pointer that indicates the unique definition of inlined code.) 
When the expression parser is looking for variables, it locates the 
DeclContext for the current context. This needs to be done carefully, 
though, e.g.:

__attribute__ ((always_inline)) void f(int a) {
  {
    int b = a * 2;
  }
}

void g() {
  f(3);
}
Here, if we're stopped in the inlined copy of f, we have to find the 
DeclContext corresponding to the definition of f – its abstract 
origin. Clang doesn't allow multiple functions with the same name and 
arguments to exist. It also means that any variables we see must be 
placed in the appropriate DeclContext.

[Bug 1]: When stopped in an inline block, the function 
GetDeclContextDIEContainingDIE for that block doesn't properly
construct a DeclContext for the abstract origin for inlined
subroutines. That means we get duplicated function DeclContexts, but
function arguments only get put in the abstract origin's DeclContext, 
and as a result when we try to look for them in nested contexts they 
aren't found.

[Bug 2]: When stopped in an inline block, the DWARF (for space 
reasons) doesn't explicitly point to the abstract origin for that 
block. This means that the function GetClangDeclContextForDIE returns
a different DeclContext for each place the block is inlined. However, 
any variables defined in the block have abstract origins, so they 
will only get placed in the DeclContext for their abstract origin.

In this fix, I've introduced a test covering both of these issues,
and fixed them.

Bug 1 could be resolved simply by making sure we look up the abstract
origin for inlined functions when looking up their DeclContexts on 
behalf of nested blocks.

For Bug 2, I've implemented an algorithm that makes the DeclContext 
for a block be the containing DeclContext for the closest entity we
would find during lookup that has an abstract origin pointer. That
means that in the following situation:

{ // block 1
  int a;
  { // block 2
    int b;
  }
}
if we looked up the DeclContext for block 2, we'd find the block 
containing the abstract origin of b, and lookup would proceed 
correctly because we'd see b and a. However, in the situation

{ // block 1
  int a;
  { // block 2
  }
}
since there isn't anything to look up in block 2, we can't determine 
its abstract origin (and there is no such pointer in the DWARF for 
blocks). However, we can walk up the parent chain and find a, and its 
abstract origin lives in the abstract origin of block 1. So we simply 
say that the DeclContext for block 2 is the same as the DeclContext 
for block 1, which contains a. Lookups will return the same results.

Thanks to Jim Ingham for review and suggestions.

Differential revision: https://reviews.llvm.org/D32375

llvm-svn: 301263
2017-04-24 22:11:10 +00:00
Zachary Turner
6f9e690199 Move Log from Core -> Utility.
All references to Host and Core have been removed, so this
class can now safely be lowered into Utility.

Differential Revision: https://reviews.llvm.org/D30559

llvm-svn: 296909
2017-03-03 20:56:28 +00:00
Zachary Turner
bf9a77305f Move classes from Core -> Utility.
This moves the following classes from Core -> Utility.

ConstString
Error
RegularExpression
Stream
StreamString

The goal here is to get lldbUtility into a state where it has
no dependendencies except on itself and LLVM, so it can be the
starting point at which to start untangling LLDB's dependencies.
These are all low level and very widely used classes, and
previously lldbUtility had dependencies up to lldbCore in order
to use these classes.  So moving then down to lldbUtility makes
sense from both the short term and long term perspective in
solving this problem.

Differential Revision: https://reviews.llvm.org/D29427

llvm-svn: 293941
2017-02-02 21:39:50 +00:00
Tamas Berghammer
7850602f0a Remove an incorrect byte size calculation in DWARFASTParserClang
llvm-svn: 291349
2017-01-07 16:39:02 +00:00
Jim Ingham
8f7db52d9d Fix incorrectly named variables.
llvm-svn: 289746
2016-12-15 00:30:30 +00:00
Sean Callanan
237c3ed95e Adopt PrettyStackTrace in LLDB
LLDB needs some minor changes to adopt PrettyStackTrace after https://reviews.llvm.org/D27683.
We remove our own SetCrashDescription() function and use LLVM-provided RAII objects instead.
We also make sure LLDB doesn't define __crashtracer_info__ which would collide with LLVM's definition.

Differential Revision: https://reviews.llvm.org/D27735

llvm-svn: 289711
2016-12-14 21:31:31 +00:00
Zachary Turner
c156427ded Don't allow direct access to StreamString's internal buffer.
This is a large API change that removes the two functions from
StreamString that return a std::string& and a const std::string&,
and instead provide one function which returns a StringRef.

Direct access to the underlying buffer violates the concept of
a "stream" which is intended to provide forward only access,
and makes porting to llvm::raw_ostream more difficult in the
future.

Differential Revision: https://reviews.llvm.org/D26698

llvm-svn: 287152
2016-11-16 21:15:24 +00:00
Zachary Turner
563d7e8a39 Fix a few warnings caught by clang.
llvm-svn: 283607
2016-10-07 21:32:16 +00:00
Zachary Turner
4fa098a5c0 Convert UniqueCStringMap to use StringRef.
llvm-svn: 283494
2016-10-06 21:22:44 +00:00
Kate Stone
b9c1b51e45 *** This commit represents a complete reformatting of the LLDB source code
*** to conform to clang-format’s LLVM style.  This kind of mass change has
*** two obvious implications:

Firstly, merging this particular commit into a downstream fork may be a huge
effort.  Alternatively, it may be worth merging all changes up to this commit,
performing the same reformatting operation locally, and then discarding the
merge for this particular commit.  The commands used to accomplish this
reformatting were as follows (with current working directory as the root of
the repository):

    find . \( -iname "*.c" -or -iname "*.cpp" -or -iname "*.h" -or -iname "*.mm" \) -exec clang-format -i {} +
    find . -iname "*.py" -exec autopep8 --in-place --aggressive --aggressive {} + ;

The version of clang-format used was 3.9.0, and autopep8 was 1.2.4.

Secondly, “blame” style tools will generally point to this commit instead of
a meaningful prior commit.  There are alternatives available that will attempt
to look through this change and find the appropriate prior commit.  YMMV.

llvm-svn: 280751
2016-09-06 20:57:50 +00:00
Pavel Labath
402c8c0716 Dwarf parser: don't lookup void typedefs in the DWO
Summary:
void typedefs do not have a DW_AT_type attribute, so we end up with an empty encoding_uid
variable. These don't need to be looked up and trying to look that will assert in a debug build.

Reviewers: clayborg

Subscribers: lldb-commits, tberghammer

Differential Revision: http://reviews.llvm.org/D22218

llvm-svn: 275164
2016-07-12 09:26:30 +00:00
Greg Clayton
87c550324c Fix it so that we only grab the typedef from the module DWARF file if the type that is typedef'ed is a declaration. This fixes the following bugs:
<rdar://problem/26870890> [PR28156] TestWithModuleDebugging.py: failing on macOS
https://llvm.org/bugs/show_bug.cgi?id=27412
https://llvm.org/bugs/show_bug.cgi?id=28156

llvm-svn: 274809
2016-07-07 23:57:39 +00:00