These checks detect potential deadlocks caused by inconsistent lock
ordering. The checks are implemented under the -Wthread-safety-beta flag.
llvm-svn: 227997
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
Original message:
Add a second late template parser callback meant to cleanup any
resources allocated by late template parsing. Call it from the
Sema::ActOnEndOfTranslationUnit method after all pending template
instantiations have been completed. Teach Parser::ParseTopLevelDecl to
install the cleanup callback when incremental processing is enabled so
that Parser::TemplateIds can be freed.
Patch by Brad King!
llvm-svn: 220400
Add a second late template parser callback meant to cleanup any
resources allocated by late template parsing. Call it from the
Sema::ActOnEndOfTranslationUnit method after all pending template
instantiations have been completed. Teach Parser::ParseTopLevelDecl to
install the cleanup callback when incremental processing is enabled so
that Parser::TemplateIds can be freed.
Patch by Brad King!
llvm-svn: 219810
Summary: This fixes PR21235.
Test Plan: Includes an automated test.
Reviewers: hansw
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D5718
llvm-svn: 219551
Summary:
This fixes PR20023. In order to implement this scoping rule, we piggy
back on the existing LabelDecl machinery, by creating LabelDecl's that
will carry the "internal" name of the inline assembly label, which we
will rewrite the asm label to.
Reviewers: rnk
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D4589
llvm-svn: 218230
The warning warns on TypedefNameDecls -- typedefs and C++11 using aliases --
that are !isReferenced(). Since the isReferenced() bit on TypedefNameDecls
wasn't used for anything before this warning it wasn't always set correctly,
so this patch also adds a few missing MarkAnyDeclReferenced() calls in
various places for TypedefNameDecls.
This is made a bit complicated due to local typedefs possibly being used only
after their local scope has closed. Consider:
template <class T>
void template_fun(T t) {
typename T::Foo s3foo; // YYY
(void)s3foo;
}
void template_fun_user() {
struct Local {
typedef int Foo; // XXX
} p;
template_fun(p);
}
Here the typedef in XXX is only used at end-of-translation unit, when YYY in
template_fun() gets instantiated. To handle this, typedefs that are unused when
their scope exits are added to a set of potentially unused typedefs, and that
set gets checked at end-of-TU. Typedefs that are still unused at that point then
get warned on. There's also serialization code for this set, so that the
warning works with precompiled headers and modules. For modules, the warning
is emitted when the module is built, for precompiled headers each time the
header gets used.
Finally, consider a function using C++14 auto return types to return a local
type defined in a header:
auto f() {
struct S { typedef int a; };
return S();
}
Here, the typedef escapes its local scope and could be used by only some
translation units including the header. To not warn on this, add a
RecursiveASTVisitor that marks all delcs on local types returned from auto
functions as referenced. (Except if it's a function with internal linkage, or
the decls are private and the local type has no friends -- in these cases, it
_is_ safe to warn.)
Several of the included testcases (most of the interesting ones) were provided
by Richard Smith.
(gcc's spelling -Wunused-local-typedefs is supported as an alias for this
warning.)
llvm-svn: 217298
This innocuous statement to get the identifier info for __va_list_tag
was causing an assertion failure:
NextIsPrevious() && "decl became non-canonical unexpectedly"
if the __va_list_tag identifier was found in a PCH in some
circumstances, because it was looked up before the ASTReader had a Sema
object to use to find existing decls to merge with.
We could possibly move getting the identifier info even later, or make
it lazy if we wanted to, but this seemed like the minimal change.
Now why a PCH would have this identifier in the first place is a bit
mysterious. This seems to be related to the global module index in some
way, because when the test case is built without the global module index
it will not emit an identifier for __va_list_tag into the PCH, but with
the global module index it does.
llvm-svn: 217275
Summary:
This pragma is very rare. We could *hypothetically* lower some uses of
it down to @llvm.global_ctors, but given that GlobalOpt isn't able to
optimize prioritized global ctors today, there's really no point.
If we wanted to do this in the future, I would check if the section used
in the pragma started with ".CRT$XC" and had up to two characters after
it. Those two characters could form the 16-bit initialization priority
that we support in @llvm.global_ctors. We would have to teach LLVM to
lower prioritized global ctors on COFF as well.
This should let us compile some silly uses of this pragma in WebKit /
Blink.
Reviewers: rsmith, majnemer
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D4549
llvm-svn: 213593
The compilation pipeline doesn't actually need to know about the high-level
concept of diagnostic mappings, and hiding the final computed level presents
several simplifications and other potential benefits.
The only exceptions are opportunistic checks to see whether expensive code
paths can be avoided for diagnostics that are guaranteed to be ignored at a
certain SourceLocation.
This commit formalizes that invariant by introducing and using
DiagnosticsEngine::isIgnored() in place of individual level checks throughout
lex, parse and sema.
llvm-svn: 211005
This patch adds support for the msvc pragmas section, bss_seg, code_seg,
const_seg and data_seg as well as support for __declspec(allocate()).
Additionally it corrects semantics and adds diagnostics for
__attribute__((section())) and the interaction between the attribute
and the msvc pragmas and declspec. In general conflicts should now be
well diganosed within and among these features.
In supporting the pragmas new machinery for uniform lexing for
msvc pragmas was introduced. The new machinery always lexes the
entire pragma and stores it on an annotation token. The parser
is responsible for parsing the pragma when the handling the
annotation token.
There is a known outstanding bug in this implementation in C mode.
Because these attributes and pragmas apply _only_ to definitions, we
process them at the time we detect a definition. Due to tentative
definitions in C, we end up processing the definition late. This means
that in C mode, everything that ends up in a BSS section will end up in
the _last_ BSS section rather than the one that was live at the time of
tentative definition, even if that turns out to be the point of actual
definition. This issue is not known to impact anything as of yet
because we are not aware of a clear use or use case for #pragma bss_seg
but should be fixed at some point.
Differential Revision=http://reviews.llvm.org/D3065#inline-16241
llvm-svn: 205810
These features are new in VS 2013 and are necessary in order to layout
std::ostream correctly. Currently we have an ABI incompatibility when
self-hosting with the 2013 stdlib in our convertible_fwd_ostream wrapper
in gtest.
This change adds another implicit attribute, MSVtorDispAttr, because
implicit attributes are currently the best way to make sure the
information stays on class templates through instantiation.
Reviewers: majnemer
Differential Revision: http://llvm-reviews.chandlerc.com/D2746
llvm-svn: 201274
These flags control the inheritance model initially used by the
translation unit.
Differential Revision: http://llvm-reviews.chandlerc.com/D2741
llvm-svn: 201175
Introduce a notion of a 'current representation method' for
pointers-to-members.
When starting out, this is set to 'best case' (representation method is
chosen by examining the class, selecting the smallest representation
that would work given the class definition or lack thereof).
This pragma allows the translation unit to dictate exactly what
representation to use, similar to how the inheritance model keywords
operate.
N.B. PCH support is forthcoming.
Differential Revision: http://llvm-reviews.chandlerc.com/D2723
llvm-svn: 201105
A return type is the declared or deduced part of the function type specified in
the declaration.
A result type is the (potentially adjusted) type of the value of an expression
that calls the function.
Rule of thumb:
* Declarations have return types and parameters.
* Expressions have result types and arguments.
llvm-svn: 200082
Fix a perennial source of confusion in the clang type system: Declarations and
function prototypes have parameters to which arguments are supplied, so calling
these 'arguments' was a stretch even in C mode, let alone C++ where default
arguments, templates and overloading make the distinction important to get
right.
Readability win across the board, especially in the casting, ADL and
overloading implementations which make a lot more sense at a glance now.
Will keep an eye on the builders and update dependent projects shortly.
No functional change.
llvm-svn: 199686
Additionally, remove the optional nature of the spelling list index when creating attributes. This is supported by table generating a Spelling enumeration when the spellings for an attribute are distinct enough to warrant it.
llvm-svn: 199378
There's been long-standing confusion over the role of these two options. This
commit makes the necessary changes to differentiate them clearly, following up
from r198936.
MicrosoftExt (aka. fms-extensions):
Enable largely unobjectionable Microsoft language extensions to ease
portability. This mode, also supported by gcc, is used for building software
like FreeBSD and Linux kernel extensions that share code with Windows drivers.
MSVCCompat (aka. -fms-compatibility, formerly MicrosoftMode):
Turn on a special mode supporting 'heinous' extensions for drop-in
compatibility with the Microsoft Visual C++ product. Standards-compilant C and
C++ code isn't guaranteed to work in this mode. Implies MicrosoftExt.
Note that full -fms-compatibility mode is currently enabled by default on the
Windows target, which may need tuning to serve as a reasonable default.
See cfe-commits for the full discourse, thread 'r198497 - Move MS predefined
type_info out of InitializePredefinedMacros'
No change in behaviour.
llvm-svn: 199209
MSVC defines size_t without any explicit declarations. This change
allows us to be compatible with TUs that depend on this declaration
appearing from nowhere.
llvm-svn: 199190
It was previously enabled in both but should only have been part of the drop-in
quirks mode that is 'MicrosoftMode' given that it's only useful for
compatibility with the Microsoft headers/runtime.
llvm-svn: 198548
Instead of keeping it in amongst the macros, build the declaration at Sema init
the same way we do with other predeclared and builtin types.
In practice this means the declaration is marked implicit and therefore won't
show up as an unwanted user-declared type in tooling which has been a
frequently reported issue (though I haven't been able to cook up a test).
llvm-svn: 198497
This commit kills off custom type specifier and keyword handling of OpenCL C
data types.
Although the OpenCL spec describes them as keywords, we can handle them more
elegantly as predefined types. This should provide better error correction and
code completion as well as simplifying the implementation.
The primary intention is however to simplify the C/C++ parser and save some
packed bits on AST structures that had been extended in r170432 just for
OpenCL.
llvm-svn: 197578
Hopefully Richard won't notice this terrible egregiocity - clearly the work of a malevolent poltergeist - fixed now ;)
No functionality change.
llvm-svn: 194439
No Functionality change.
This refactoring avoids having to call getCurLambda right after PushLambdaScope, to obtain the LambdaScopeInfo that was created during the call to PushLambdaScope.
llvm-svn: 194438
Delayed exception specification checking for defaulted members and virtual
destructors are both susceptible to mutation during iteration so we need to
swap and process the worklists.
This resolves both accepts-invalid and rejects-valid issues and moreover fixes
potential invalid memory access as the contents of the vectors change during
iteration and recursive template instantiation.
Checking can be further delayed where parent classes aren't yet fully defined.
This patch adds two assertions at end of TU to ensure no specs are left
unchecked as was happenning before the fix, plus a test case from Marshall Clow
for the defaulted member crash extracted from the libcxx headers.
Reviewed by Richard Smith.
llvm-svn: 192947
Delayed exception specification checking for defaulted members and virtual
destructors are both susceptible to mutation during iteration so we need to
process the worklists fully.
This resolves both accepts-invalid and rejects-valid issues and moreover fixes
potential invalid memory access as the contents of the vectors change during
iteration and recursive template instantiation.
This patch also adds two assertions at end of TU to ensure no specs are left
unchecked as was happenning before the fix, plus a test case from Marshall Clow
for the defaulted member crash extracted from the libcxx headers.
Reviewed by Richard Smith.
llvm-svn: 192914
Specifically, the following features are not included in this commit:
- any sort of capturing within generic lambdas
- generic lambdas within template functions and nested
within other generic lambdas
- conversion operator for captureless lambdas
- ensuring all visitors are generic lambda aware
(Although I have gotten some useful feedback on my patches of the above and will be incorporating that as I submit those patches for commit)
As an example of what compiles through this commit:
template <class F1, class F2>
struct overload : F1, F2 {
using F1::operator();
using F2::operator();
overload(F1 f1, F2 f2) : F1(f1), F2(f2) { }
};
auto Recursive = [](auto Self, auto h, auto ... rest) {
return 1 + Self(Self, rest...);
};
auto Base = [](auto Self, auto h) {
return 1;
};
overload<decltype(Base), decltype(Recursive)> O(Base, Recursive);
int num_params = O(O, 5, 3, "abc", 3.14, 'a');
Please see attached tests for more examples.
This patch has been reviewed by Doug and Richard. Minor changes (non-functionality affecting) have been made since both of them formally looked at it, but the changes involve removal of supernumerary return type deduction changes (since they are now redundant, with richard having committed a recent patch to address return type deduction for C++11 lambdas using C++14 semantics).
Some implementation notes:
- Add a new Declarator context => LambdaExprParameterContext to
clang::Declarator to allow the use of 'auto' in declaring generic
lambda parameters
- Add various helpers to CXXRecordDecl to facilitate identifying
and querying a closure class
- LambdaScopeInfo (which maintains the current lambda's Sema state)
was augmented to house the current depth of the template being
parsed (id est the Parser calls Sema::RecordParsingTemplateParameterDepth)
so that SemaType.cpp::ConvertDeclSpecToType may use it to immediately
generate a template-parameter-type when 'auto' is parsed in a generic
lambda parameter context. (i.e we do NOT use AutoType deduced to
a template parameter type - Richard seemed ok with this approach).
We encode that this template type was generated from an auto by simply
adding $auto to the name which can be used for better diagnostics if needed.
- SemaLambda.h was added to hold some common lambda utility
functions (this file is likely to grow ...)
- Teach Sema::ActOnStartOfFunctionDef to check whether it
is being called to instantiate a generic lambda's call
operator, and if so, push an appropriately prepared
LambdaScopeInfo object on the stack.
- various tests were added - but much more will be needed.
There is obviously more work to be done, and both Richard (weakly) and Doug (strongly)
have requested that LambdaExpr be removed form the CXXRecordDecl LambdaDefinitionaData
in a future patch which is forthcoming.
A greatful thanks to all reviewers including Eli Friedman, James Dennett,
and especially the two gracious wizards (Richard Smith and Doug Gregor)
who spent hours providing feedback (in person in Chicago and on the mailing lists).
And yet I am certain that I have allowed unidentified bugs to creep in; bugs, that I will do my best to slay, once identified!
Thanks!
llvm-svn: 191453
Review: http://llvm-reviews.chandlerc.com/D1546.
I have picked up this patch form Lawrence
(http://llvm-reviews.chandlerc.com/D1063) and did a few changes.
From the original change description (updated as appropriate):
This patch adds a check that ensures that modules only use modules they
have so declared. To this end, it adds a statement on intended module
use to the module.map grammar:
use module-id
A module can then only use headers from other modules if it 'uses' them.
This enforcement is off by default, but may be turned on with the new
option -fmodules-decluse.
When enforcing the module semantics, we also need to consider a source
file part of a module. This is achieved with a compiler option
-fmodule-name=<module-id>.
The compiler at present only applies restrictions to the module directly
being built.
llvm-svn: 191283
When a comma occurs in a default argument or default initializer within a
class, disambiguate whether it is part of the initializer or whether it ends
the initializer.
The way this works (which I will be proposing for standardization) is to treat
the comma as ending the default argument or default initializer if the
following token sequence matches the syntactic constraints of a
parameter-declaration-clause or init-declarator-list (respectively).
This is both consistent with the disambiguation rules elsewhere (where entities
are treated as declarations if they can be), and should have no regressions
over our old behavior. I think it might also disambiguate all cases correctly,
but I don't have a proof of that.
There is an annoyance here: because we're performing a tentative parse in a
situation where we may not have seen declarations of all relevant entities (if
the comma is part of the initializer, lookup may find entites declared later in
the class), we need to turn off typo-correction and diagnostics during the
tentative parse, and in the rare case that we decide the comma is part of the
initializer, we need to revert all token annotations we performed while
disambiguating.
Any diagnostics that occur outside of the immediate context of the tentative
parse (for instance, if we trigger the implicit instantiation of a class
template) are *not* suppressed, mirroring the usual rules for a SFINAE context.
llvm-svn: 190639
With r190382, -Wunused-variable warns about unused const variables when
appropriate. For codebases that use -Werror, this poses a problem as
existing unused const variables need to be cleaned up first. To make the
transistion easier, this patch splits -Wunused-variable by pulling out
an additional -Wunused-const-variable (by default activated along with
-Wunused-variable).
llvm-svn: 190508
Make sure we perform the correct "referenced-but-not-used" check for
static member constants.
Fixes bug reported on cfe-commits by Alexey Samsonov.
llvm-svn: 190437
This patch does a few different things.
This patch improves unused var diags for const vars: we no longer
unconditionally suppress diagnostics for const vars, instead only suppressing
the diagnostic when the declaration appears to be useful.
This patch also makes us more consistently use whether a variable/function
is declared in the main file to suppress diagnostics where appropriate.
Fixes <rdar://problem/14907887>.
llvm-svn: 190382
Specifically, the following features are not included in this commit:
- any sort of capturing within generic lambdas
- nested lambdas
- conversion operator for captureless lambdas
- ensuring all visitors are generic lambda aware
As an example of what compiles:
template <class F1, class F2>
struct overload : F1, F2 {
using F1::operator();
using F2::operator();
overload(F1 f1, F2 f2) : F1(f1), F2(f2) { }
};
auto Recursive = [](auto Self, auto h, auto ... rest) {
return 1 + Self(Self, rest...);
};
auto Base = [](auto Self, auto h) {
return 1;
};
overload<decltype(Base), decltype(Recursive)> O(Base, Recursive);
int num_params = O(O, 5, 3, "abc", 3.14, 'a');
Please see attached tests for more examples.
Some implementation notes:
- Add a new Declarator context => LambdaExprParameterContext to
clang::Declarator to allow the use of 'auto' in declaring generic
lambda parameters
- Augment AutoType's constructor (similar to how variadic
template-type-parameters ala TemplateTypeParmDecl are implemented) to
accept an IsParameterPack to encode a generic lambda parameter pack.
- Add various helpers to CXXRecordDecl to facilitate identifying
and querying a closure class
- LambdaScopeInfo (which maintains the current lambda's Sema state)
was augmented to house the current depth of the template being
parsed (id est the Parser calls Sema::RecordParsingTemplateParameterDepth)
so that Sema::ActOnLambdaAutoParameter may use it to create the
appropriate list of corresponding TemplateTypeParmDecl for each
auto parameter identified within the generic lambda (also stored
within the current LambdaScopeInfo). Additionally,
a TemplateParameterList data-member was added to hold the invented
TemplateParameterList AST node which will be much more useful
once we teach TreeTransform how to transform generic lambdas.
- SemaLambda.h was added to hold some common lambda utility
functions (this file is likely to grow ...)
- Teach Sema::ActOnStartOfFunctionDef to check whether it
is being called to instantiate a generic lambda's call
operator, and if so, push an appropriately prepared
LambdaScopeInfo object on the stack.
- Teach Sema::ActOnStartOfLambdaDefinition to set the
return type of a lambda without a trailing return type
to 'auto' in C++1y mode, and teach the return type
deduction machinery in SemaStmt.cpp to process either
C++11 and C++14 lambda's correctly depending on the flag.
- various tests were added - but much more will be needed.
A greatful thanks to all reviewers including Eli Friedman,
James Dennett and the ever illuminating Richard Smith. And
yet I am certain that I have allowed unidentified bugs to creep in;
bugs, that I will do my best to slay, once identified!
Thanks!
llvm-svn: 188977
Basically, isInMainFile considers line markers, and isWrittenInMainFile
doesn't. Distinguishing between the two is useful when dealing with
files which are preprocessed files or rewritten with -frewrite-includes
(so we don't, for example, print useless warnings).
llvm-svn: 188968
sufficient to only consider names visible at the point of instantiation,
because that may not include names that were visible when the template was
defined. More generally, if the instantiation backtrace goes through a module
M, then every declaration visible within M should be available to the
instantiation. Any of those declarations might be part of the interface that M
intended to export to a template that it instantiates.
The fix here has two parts:
1) If we find a non-visible declaration during name lookup during template
instantiation, check whether the declaration was visible from the defining
module of all entities on the active template instantiation stack. The defining
module is not the owning module in all cases: we look at the module in which a
template was defined, not the module in which it was first instantiated.
2) Perform pending instantiations at the end of a module, not at the end of the
translation unit. This is general goodness, since it significantly cuts down
the amount of redundant work that is performed in every TU importing a module,
and also implicitly adds the module containing the point of instantiation to
the set of modules checked for declarations in a lookup within a template
instantiation.
There's a known issue here with template instantiations performed while
building a module, if additional imports are added later on. I'll fix that
in a subsequent commit.
llvm-svn: 187167
Still missing cases for templates, but this is a step in the right
direction. Also omits suggestions that would be ambiguous (eg: void
func(int = 0); + void func(float = 0); func;)
llvm-svn: 183173
This patch renames getLinkage to getLinkageInternal. Only code that
needs to handle UniqueExternalLinkage specially should call this.
Linkage, as defined in the c++ standard, is provided by
getFormalLinkage. It maps UniqueExternalLinkage to ExternalLinkage.
Most places in the compiler actually want isExternallyVisible, which
handles UniqueExternalLinkage as internal.
llvm-svn: 181677
Move the creation of CapturedStmt parameters out of CodeGen and into
Sema, making it easier to customize the outlined function. The
ImplicitParamDecls are stored in the CapturedDecl using an
ASTContext-allocated array.
Differential Revision: http://llvm-reviews.chandlerc.com/D722
llvm-svn: 181043
Add a CapturedStmt.h similar to Lambda.h to reduce the typing required to get
to the CapturedRegionKind enum. This also allows codegen to access this enum
without including Sema/ScopeInfo.h.
Also removes some duplicated code for capturing 'this' between CapturedStmt and
Lambda.
Differential Revision: http://llvm-reviews.chandlerc.com/D712
llvm-svn: 180710
Add CapturedDecl to be the DeclContext for CapturedStmt, and perform semantic
analysis. Currently captures all variables by reference.
TODO: templates
Author: Ben Langmuir <ben.langmuir@intel.com>
Differential Revision: http://llvm-reviews.chandlerc.com/D433
llvm-svn: 179618
fact be defined and used in another TU.
Reshuffle some test cases because we suppress -Wunused-variable after we've
emitted an error.
This fixes PR15558.
llvm-svn: 179138
http://lab.llvm.org:8011/builders/clang-x86_64-darwin10-gdb went back green
before it processed the reverted 178663, so it could not have been the culprit.
Revert "Revert 178663."
This reverts commit 4f8a3eb2ce5d4ba422483439e20c8cbb4d953a41.
llvm-svn: 178682
For variables and functions clang used to store two storage classes. The one
"as written" in the code and a patched one, which, for example, propagates
static to the following decls.
This apparently is from the days clang lacked linkage computation. It is now
redundant and this patch removes it.
llvm-svn: 178663
This created 2 issues:
1) Performance issue, since typo-correction with PCH/modules is rather expensive.
2) Correctness issue, since if it managed to "correct" 'super' then bogus compiler errors would
be emitted, like this:
3.m:8:3: error: unknown type name 'super'; did you mean 'super1'?
super.x = 0;
^~~~~
super1
t3.m:5:13: note: 'super1' declared here
typedef int super1;
^
t3.m:8:8: error: expected identifier or '('
super.x = 0;
^
llvm-svn: 177126
Before this patch we would compute the linkage lazily and cache it. When the
AST was modified in ways that could change the value, we would invalidate the
cache.
That was fairly brittle, since any code could ask for the a linkage before
the correct value was available.
We should change the API to one where the linkage is computed explicitly and
trying to get it when it is not available asserts.
This patch is a first step in that direction. We still compute the linkage
lazily, but instead of invalidating a cache, we assert that the AST
modifications didn't change the result.
llvm-svn: 176999
for the data specific to a macro definition (e.g. what the tokens are), and
MacroDirective class which encapsulates the changes to the "macro namespace"
(e.g. the location where the macro name became active, the location where it was undefined, etc.)
(A MacroDirective always points to a MacroInfo object.)
Usually a macro definition (MacroInfo) is where a macro name becomes active (MacroDirective) but
splitting the concepts allows us to better model the effect of modules to the macro namespace
(also as a bonus it allows better modeling of push_macro/pop_macro #pragmas).
Modules can have their own macro history, separate from the local (current translation unit)
macro history; MacroDirectives will be used to model the macro history (changes to macro namespace).
For example, if "@import A;" imports macro FOO, there will be a new local MacroDirective created
to indicate that "FOO" became active at the import location. Module "A" itself will contain another
MacroDirective in its macro history (at the point of the definition of FOO) and both MacroDirectives
will point to the same MacroInfo object.
Introducing the separation of macro concepts is the first part towards better modeling of module macros.
llvm-svn: 175585
never key functions. We did not implement that rule for the
iOS ABI, which was driven by what was implemented in gcc-4.2.
However, implement it now for other ARM-based platforms.
llvm-svn: 173515
In the source
static void f();
static void f();
template<typename T>
static void g() {
f();
}
static void f() {
}
void h() {
g<int>();
}
the call to f refers to the second decl, but it is only marked used at the end
of the translation unit during instantiation, after the third f decl has been
linked in.
With this patch we mark all subsequent decls used, so that it is easy to check
if a symbol is used or not.
llvm-svn: 171888
This fixes pr14736. It is fairly ugly, but I don't think we can do much better
as we have to wait at least until the end of the typedef to know if the
function will have external linkage or not.
llvm-svn: 171240
uncovered.
This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.
I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.
llvm-svn: 169237
defined without a previous declaration. This is similar to
-Wmissing-prototypes, but for variables instead of functions.
Patch by Ed Schouten.
llvm-svn: 166498
The infrastructure for -Warc-repeated-use-of-weak got a little too heavy
to leave sitting at the top of Sema.cpp.
No functionality change.
llvm-svn: 164856
Like properties, loading from a weak ivar twice in the same function can
give you inconsistent results if the object is deallocated between the
two loads. It is safer to assign to a strong local variable and use that.
Second half of <rdar://problem/12280249>.
llvm-svn: 164855
The motivating example:
if (self.weakProp)
use(self.weakProp);
As with any non-atomic test-then-use, it is possible a weak property to be
non-nil at the 'if', but be deallocated by the time it is used. The correct
way to write this example is as follows:
id tmp = self.weakProp;
if (tmp)
use(tmp);
The warning is controlled by -Warc-repeated-use-of-receiver, and uses the
property name and base to determine if the same property on the same object
is being accessed multiple times. In cases where the base is more
complicated than just a single Decl (e.g. 'foo.bar.weakProp'), it picks a
Decl for some degree of uniquing and reports the problem under a subflag,
-Warc-maybe-repeated-use-of-receiver. This gives a way to tune the
aggressiveness of the warning for a particular project.
The warning is not on by default because it is not flow-sensitive and thus
may have a higher-than-acceptable rate of false positives, though it is
less noisy than -Wreceiver-is-weak. On the other hand, it will not warn
about some cases that may be legitimate issues that -Wreceiver-is-weak
will catch, and it does not attempt to reason about methods returning weak
values.
Even though this is not a real "analysis-based" check I've put the bug
emission code in AnalysisBasedWarnings for two reasons: (1) to run on
every kind of code body (function, method, block, or lambda), and (2) to
suggest that it may be enhanced by flow-sensitive analysis in the future.
The second (smaller) half of this work is to extend it to weak locals
and weak ivars. This should use most of the same infrastructure.
Part of <rdar://problem/12280249>
llvm-svn: 164854
function being instantiated. An error recovery codepath was recursively
performing name lookup (and triggering an unbounded stack of template
instantiations which blew out the stack before hitting the depth limit).
Patch by Wei Pan!
llvm-svn: 164586
passing -fretain-comments-from-system-headers. By default, the
compiler no longer parses such documentation comments, as they
can result in a noticeable compile time/PCH slowdown.
Fixes <rdar://problem/11860820>.
llvm-svn: 163778
* Retain comments in the AST
* Serialize/deserialize comments
* Find comments attached to a certain Decl
* Expose raw comment text and SourceRange via libclang
llvm-svn: 158771
overload candidate, and include its message in any subsequent 'candidate not
viable due to substitution failure' note we may produce.
To keep the note small (since the 'overload resolution failed' diagnostics are
often already very verbose), the text of the SFINAE diagnostic is included as
part of the text of the note, and any notes which were attached to it are
discarded.
There happened to be spare space in OverloadCandidate into which a
PartialDiagnosticAt could be squeezed, and this patch goes to lengths to avoid
unnecessary PartialDiagnostic copies, resulting in no slowdown that I could
measure. (Removal in passing of some PartialDiagnostic copies has resulted in a
slightly smaller clang binary overall.) Even on a torture test, I was unable to
measure a memory increase of above 0.2%.
llvm-svn: 156297
so that we actually accumulate all the delayed diagnostics. Do
this so that we can restore those diagnostics to good standing
if it turns out that we were wrong to suppress, e.g. if the
tag specifier is actually an elaborated type specifier and not
a declaration.
llvm-svn: 156291
in the declaration of a non-static member function after the
(optional) cv-qualifier-seq, which in practice means in the exception
specification and late-specified return type.
The new scheme here used to manage 'this' outside of a member function
scope is more general than the Scope-based mechanism previously used
for non-static data member initializers and late-parsesd attributes,
because it can also handle the cv-qualifiers on the member
function. Note, however, that a separate pass is required for static
member functions to determine whether 'this' was used, because we
might not know that we have a static function until after declaration
matching.
Finally, this introduces name mangling for 'this' and for the implicit
'this', which is intended to match GCC's mangling. Independent
verification for the new mangling test case would be appreciated.
Fixes PR10036 and PR12450.
llvm-svn: 154799
- As with DiagnosticBuilder, it is very important that SemaDiagnosticBuilder be
completely inline to ensure that the compiler can rip it apart and sink it to
registers.
This is good for another 30k reduction in code size.
llvm-svn: 152708
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
The bug that was caught by Apple's internal buildbots was valid and also showed another bug in my implementation.
These are now fixed, with regression tests added to catch them both (not Darwin-specific).
Original log:
====================
Revert r151638 because it causes assertion hit on PCH creation for Cocoa.h
Original log:
---------------------
Correctly track tags and enum members defined in the prototype of a function, and ensure they are properly scoped.
This fixes code such as:
enum e {x, y};
int f(enum {y, x} n) {
return 0;
}
This finally fixes PR5464 and PR5477.
---------------------
I also reverted r151641 which was enhancement on top of r151638.
====================
llvm-svn: 151712
Original log:
---------------------
Correctly track tags and enum members defined in the prototype of a function, and ensure they are properly scoped.
This fixes code such as:
enum e {x, y};
int f(enum {y, x} n) {
return 0;
}
This finally fixes PR5464 and PR5477.
---------------------
I also reverted r151641 which was enhancement on top of r151638.
llvm-svn: 151667
function call (or a comma expression with a function call on its right-hand
side), possibly parenthesized, then the return type is not required to be
complete and a temporary is not bound. Other subexpressions inside a decltype
expression do not get this treatment.
This is implemented by deferring the relevant checks for all calls immediately
within a decltype expression, then, when the expression is fully-parsed,
checking the relevant constraints and stripping off any top-level temporary
binding.
Deferring the completion of the return type exposed a bug in overload
resolution where completion of the argument types was not attempted, which
is also fixed by this change.
llvm-svn: 151117
default arguments of function parameters. This simple-sounding task is
complicated greatly by two issues:
(1) Default arguments aren't actually a real context, so we need to
maintain extra state within lambda expressions to track when a
lambda was actually in a default argument.
(2) At the time that we parse a default argument, the FunctionDecl
doesn't exist yet, so lambda closure types end up in the enclosing
context. It's not clear that we ever want to change that, so instead
we introduce the notion of the "effective" context of a declaration
for the purposes of name mangling.
llvm-svn: 151011
* if, switch, range-based for: warn if semicolon is on the same line.
* for, while: warn if semicolon is on the same line and either next
statement is compound statement or next statement has more
indentation.
Replacing the semicolon with {} or moving the semicolon to the next
line will always silence the warning.
Tests from SemaCXX/if-empty-body.cpp merged into SemaCXX/warn-empty-body.cpp.
llvm-svn: 150515
Parsing of @implementations was based on modifying global state from
the parser; the logic for late parsing of methods was spread in multiple places
making it difficult to have a robust error recovery.
-it was difficult to ensure that we don't neglect parsing the lexed methods.
-it was difficult to setup the original objc container context for parsing the lexed methods
after completing ParseObjCAtImplementationDeclaration and returning to top level context.
Enhance parsing of @implementations by centralizing it in Parser::ParseObjCAtImplementationDeclaration().
ParseObjCAtImplementationDeclaration now returns only after an @implementation is fully parsed;
all the data and logic for late parsing of methods is now in one place.
This allows us to provide code-completion for late parsed methods with mis-matched braces.
rdar://10775381
llvm-svn: 149987
return pre-built lists. Instead, it feeds the methods it deserializes
to Sema so that Sema can unique them, which keeps the chains shorter.
llvm-svn: 148889
does not depend on Sema, it accepts an ASTContext and a Preprocessor.
Step towards making clang_getCursorCompletionString not depend on Sema.
llvm-svn: 148278
we have a redeclarable type, and only use the new virtual versions
(getPreviousDeclImpl() and getMostRecentDeclImpl()) when we don't have
that type information. This keeps us from penalizing users with strict
type information (and is the moral equivalent of a "final" method).
Plus, settle on the names getPreviousDecl() and getMostRecentDecl()
throughout.
llvm-svn: 148187
in the module map. This provides a bit more predictability for the
user, as well as eliminating the need to sort the submodules when
serializing them.
llvm-svn: 147564
within module maps, which will (eventually) be used to re-export a
module from another module. There are still some pieces missing,
however.
llvm-svn: 145665
them when performing a const conversion on the implicit object argument for a
member operator call on an rvalue.
No change to the testsuite: the test for this change is that the added
assertion does not fire any more.
llvm-svn: 144333
AST file more lazy, so that we don't eagerly load that information for
all known identifiers each time a new AST file is loaded. The eager
reloading made some sense in the context of precompiled headers, since
very few identifiers were defined before PCH load time. With modules,
however, a huge amount of code can get parsed before we see an
@import, so laziness becomes important here.
The approach taken to make this information lazy is fairly simple:
when we load a new AST file, we mark all of the existing identifiers
as being out-of-date. Whenever we want to access information that may
come from an AST (e.g., whether the identifier has a macro definition,
or what top-level declarations have that name), we check the
out-of-date bit and, if it's set, ask the AST reader to update the
IdentifierInfo from the AST files. The update is a merge, and we now
take care to merge declarations before/after imports with declarations
from multiple imports.
The results of this optimization are fairly dramatic. On a small
application that brings in 14 non-trivial modules, this takes modules
from being > 3x slower than a "perfect" PCH file down to 30% slower
for a full rebuild. A partial rebuild (where the PCH file or modules
can be re-used) is down to 7% slower. Making the PCH file just a
little imperfect (e.g., adding two smallish modules used by a bunch of
.m files that aren't in the PCH file) tips the scales in favor of the
modules approach, with 24% faster partial rebuilds.
This is just a first step; the lazy scheme could possibly be improved
by adding versioning, so we don't search into modules we already
searched. Moreover, we'll need similar lazy schemes for all of the
other lookup data structures, such as DeclContexts.
llvm-svn: 143100
and DefaultFunctionArrayLvalueConversion. To prevent
significant regression for should-this-be-a-call fixits,
and to repair some such regression from the introduction of
bound member placeholders, make those placeholder checks
try to build calls appropriately. Harden the build-a-call
logic while we're at it.
llvm-svn: 141738
from unfriendly (== not at all modularized) directories. This is
temporary, and it only affects module construction until I'll figured
out how to deal with system headers.
llvm-svn: 140159
than conversions of C pointers to ObjC pointers. In order to ensure that
we've caught every case, add asserts to CastExpr that strictly determine
which cast kind is used for which kind of bit cast.
llvm-svn: 139352
from the given source. -emit-module behaves similarly to -emit-pch,
except that Sema is somewhat more strict about the contents of
-emit-module. In the future, there are likely to be more interesting
differences.
llvm-svn: 138595
type over into the AST context, then make that declaration a
predefined declaration in the AST format. This ensures that different
AST files will at least agree on the (global) declaration ID for 'id',
and eliminates one of the "special" types in the AST file format.
llvm-svn: 137429
ASTContext with accessors/mutators. The only functional change is that
the AST writer won't bother writing the id/Class/SEL redefinition type
if it hasn't been explicitly set; previously, it ended up being
written as a synonym for the built-in id/Class/SEL.
llvm-svn: 137349
- Added LazyVector::erase() to support this use case.
- Factored out the LazyDecl-of-Decls to RecordData translation in
the ASTWriter. There is still a pile of code duplication here to
eliminate.
llvm-svn: 136270
contents are lazily loaded on demand from an external source (e.g., an
ExternalASTSource or ExternalSemaSource). The "loaded" entities are
kept separate from the "local" entities, so that the two can grow
independently.
Switch Sema::TentativeDefinitions from a normal vector that is eagerly
populated by the ASTReader into one of these LazyVectors, making the
ASTReader a bit more like me (i.e., lazy).
llvm-svn: 136262
FullSourceLoc::getInstantiationLoc to ...::getExpansionLoc. This is part
of the API and documentation update from 'instantiation' as the term for
macros to 'expansion'.
llvm-svn: 135914
Special detail is added for uninitialized variable analysis as this has
serious performance problems than need to be tracked.
Computing some of this data is expensive, for example walking the CFG to
determine its size. To avoid doing that unless the stats data is going
to be used, we thread a bit into the Sema object to track whether
detailed stats should be collected or not. This bit is used to avoid
computations whereever the computations are likely to be more expensive
than checking the state of the flag. Thus, counters are in some cases
unconditionally updated, but the more expensive (and less frequent)
aggregation steps are skipped.
With this patch, we're able to see that for 'gcc.c':
*** Analysis Based Warnings Stats:
232 functions analyzed (0 w/o CFGs).
7151 CFG blocks built.
30 average CFG blocks per function.
1167 max CFG blocks per function.
163 functions analyzed for uninitialiazed variables
640 variables analyzed.
3 average variables per function.
94 max variables per function.
96409 block visits.
591 average block visits per function.
61546 max block visits per function.
And for the reduced testcase in PR10183:
*** Analysis Based Warnings Stats:
98 functions analyzed (0 w/o CFGs).
8526 CFG blocks built.
87 average CFG blocks per function.
7277 max CFG blocks per function.
68 functions analyzed for uninitialiazed variables
1359 variables analyzed.
19 average variables per function.
1196 max variables per function.
2540494 block visits.
37360 average block visits per function.
2536495 max block visits per function.
That last number is the somewhat scary one that indicates the problem in
PR10183.
llvm-svn: 134494
vector<int>
to
std::vector<int>
Patch by Kaelyn Uhrain, with minor tweaks + PCH support from me. Fixes
PR5776/<rdar://problem/8652971>.
Thanks Kaelyn!
llvm-svn: 134007
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
We can use this to produce nice diagnostics (and try to fixit-and-recover) in
various cases where we might see "MyFunction" instead of "MyFunction()". The
changes in SemaExpr are an example of how to use isExprCallable.
llvm-svn: 130878
This is more efficient as it's all done at once at the end of the TU.
This could still get expensive, so a flag is provided to disable it. As
an added bonus, the diagnostics will now print out a cycle.
The PCH test is XFAILed because we currently can't deal with a note
emitted in the header and I, being tired, see no other way to verify the
serialization of delegating constructors. We should probably address
this problem /somehow/ but no good solution comes to mind.
llvm-svn: 130836
new templates that need to be instantiated and vice-versa. Iterate
until we've instantiated all required templates and defined all
required vtables. Fixed PR9325 / <rdar://problem/9055177>.
llvm-svn: 130023
gcc's unused warnings which don't get emitted if the function is referenced even in an unevaluated context
(e.g. in templates, sizeof, etc.). Also, saying that a function is 'unused' because it won't get codegen'ed
is somewhat misleading.
- Don't emit 'unused' warnings for functions that are referenced in any part of the user's code.
- A warning that an internal function/variable won't get emitted is useful though, so introduce
-Wunneeded-internal-declaration which will warn if a function/variable with internal linkage is not
"needed" ('used' from the codegen perspective), e.g:
static void foo() { }
template <int>
void bar() {
foo();
}
test.cpp:1:13: warning: function 'foo' is not needed and will not be emitted
static void foo() { }
^
Addresses rdar://8733476.
llvm-svn: 129794
This patch authored by Eric Niebler.
Many methods on the Sema class (e.g. ConvertPropertyForRValue) take Expr
pointers as in/out parameters (Expr *&). This is especially true for the
routines that apply implicit conversions to nodes in-place. This design is
workable only as long as those conversions cannot fail. If they are allowed
to fail, they need a way to report their failures. The typical way of doing
this in clang is to use an ExprResult, which has an extra bit to signal a
valid/invalid state. Returning ExprResult is de riguour elsewhere in the Sema
interface. We suggest changing the Expr *& parameters in the Sema interface
to ExprResult &. This increases interface consistency and maintainability.
This interface change is important for work supporting MS-style C++
properties. For reasons explained here
<http://lists.cs.uiuc.edu/pipermail/cfe-dev/2011-February/013180.html>,
seemingly trivial operations like rvalue/lvalue conversions that formerly
could not fail now can. (The reason is that given the semantics of the
feature, getter/setter method lookup cannot happen until the point of use, at
which point it may be found that the method does not exist, or it may have the
wrong type, or overload resolution may fail, or it may be inaccessible.)
llvm-svn: 129143
diagnostics that occur in unreachable code (e.g., -Warray-bound).
We only pay the cost of doing the reachability analysis when we issue one of these diagnostics.
llvm-svn: 126290
* Flag indicating 'we're parsing this auto typed variable's initializer' moved from VarDecl to Sema
* Temporary template parameter list for auto deduction is now allocated on the stack.
* Deduced 'auto' types are now uniqued.
llvm-svn: 126139
without defining them. This should be an error, but I'm paranoid about
"uses" that end up not actually requiring a definition. I'll revisit later.
Also, teach IR generation to not set internal linkage on variable
declarations, just for safety's sake. Doing so produces an invalid module
if the variable is not ultimately defined.
Also, fix several places in the test suite where we were using internal
functions without definitions.
llvm-svn: 126016
making them be template instantiated in a more normal way and
make them handle attributes like other decls.
This fixes the used/unused label handling stuff, making it use
the same infrastructure as other decls.
llvm-svn: 125771
LabelDecl and LabelStmt. There is a 1-1 correspondence between the
two, but this simplifies a bunch of code by itself. This is because
labels are the only place where we previously had references to random
other statements, causing grief for AST serialization and other stuff.
This does cause one regression (attr(unused) doesn't silence unused
label warnings) which I'll address next.
This does fix some minor bugs:
1. "The only valid attribute " diagnostic was capitalized.
2. Various diagnostics printed as ''labelname'' instead of 'labelname'
3. This reduces duplication of label checking between functions and blocks.
Review appreciated, particularly for the cindex and template bits.
llvm-svn: 125733
access-control diagnostics which arise from the portion of the declarator
following the scope specifier, just in case access is granted by
friending the individual method. This can also happen with in-line
member function declarations of class templates due to templated-scope
friend declarations.
We were really playing fast-and-loose before with this sort of thing,
and it turned out to work because *most* friend functions are in file
scope. Making us delay regardless of context exposed several bugs with
how we were manipulating delay. I ended up needing a concept of a
context that's independent of the declarations in which it appears,
and then I actually had to make some things save contexts correctly,
but delay should be much cleaner now.
I also encapsulated all the delayed-diagnostics machinery in a single
subobject of Sema; this is a pattern we might want to consider rolling
out to other components of Sema.
llvm-svn: 125485
access control errors into SFINAE errors, so that the trait provides
enough support to implement the C++0x std::is_convertible type trait.
To get there, the SFINAETrap now knows how to set up a SFINAE context
independent of any template instantiations or template argument
deduction steps, and (separately) can set a Sema flag to translate
access control errors into SFINAE errors. The latter can also be
useful if we decide that access control errors during template argument
deduction should cause substitution failure (rather than a hard error)
as has been proposed for C++0x.
llvm-svn: 124446
whose patterns are template arguments. We can now instantiate, e.g.,
typedef tuple<pair<OuterTypes, InnerTypes>...> type;
where OuterTypes and InnerTypes are template type parameter packs.
There is a horrible inefficiency in
TemplateArgumentLoc::getPackExpansionPattern(), where we need to
create copies of TypeLoc data because our interfaces traffic in
TypeSourceInfo pointers where they should traffic in TypeLocs
instead. I've isolated in efficiency in this one routine; once we
refactor our interfaces to traffic in TypeLocs, we can eliminate it.
llvm-svn: 122278
a translation unit to the ActOnEndOfTranslationUnit function instead of doing
it at the start of DefineUsedVTables. The latter is now called *recursively*
during template instantiation, which causes an absolutely insane number of
walks of every record decl in the translation unit.
After this patch, an extremely template instantiation heavy test case's compile
time drops by 10x, and we see between 15% and 20% improvement in average
compile times across a project. This is just recovering a regression, it
doesn't make anything faster than it was several weeks ago.
llvm-svn: 121644
a useful template instantiation stack. Fixes PR8640.
This also causes a slight change to where the "instantianted from" note shows up
in truly esoteric cases (see the change to test/SemaCXX/destructor.cpp), but
that isn't directly the fault of this patch.
llvm-svn: 120135
-Move the stuff of Diagnostic related to creating/querying diagnostic IDs into a new DiagnosticIDs class.
-DiagnosticIDs can be shared among multiple Diagnostics for multiple translation units.
-The rest of the state in Diagnostic object is considered related and tied to one translation unit.
-Have Diagnostic point to the SourceManager that is related with. Diagnostic can now accept just a
SourceLocation instead of a FullSourceLoc.
-Reflect the changes to various interfaces.
llvm-svn: 119730
that are suppressed during template argument deduction. This change
queues diagnostics computed during template argument deduction. Then,
if the resulting function template specialization or partial
specialization is chosen by overload resolution or partial ordering
(respectively), we will emit the queued diagnostics at that point.
This addresses most of PR6784. However, the check for unnamed/local
template arguments (which existed before this change) is still only
skin-deep, and needs to be extended to look deeper into types. It must
be improved to finish PR6784.
llvm-svn: 116373
typeid expressions:
- make sure we have a proper source location for the closing ')'
- cache the declaration of std::type_info once we've found it
llvm-svn: 113441
One who seeks the Tao unlearns something new every day.
Less and less remains until you arrive at non-action.
When you arrive at non-action,
nothing will be left undone.
llvm-svn: 112244
This works courtesy of the new SmallVector<..., 0> specialization that
doesn't require a complete type. Note that you'll need to pull at least
SmallVector.h from LLVM to compile successfully.
llvm-svn: 112114
token. The first token might be something that ends up triggering code
completion, which in turn requires a valid Scope. Test case forthcoming.
llvm-svn: 112066
Reid Kleckner