Summary:
This patch aims to fix the bug reported at
https://bugs.llvm.org/show_bug.cgi?id=33189. Clang hits an assertion
when a template destructor declaration is present. This is caused by
later processing that does not expect to encounter a template when
looking at a destructor. The resolution is to treat the destructor as
being not declared when later processing is interested in the properties
of the destructor of a class.
Reviewers: rcraik, hubert.reinterpretcast, aaron.ballman, rsmith
Reviewed By: rsmith
Subscribers: rsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D33833
Patch by Kuang He!
llvm-svn: 306905
When looking for the template instantiation pattern of a templated entity,
consistently select the definition of the pattern if there is one. This means
we'll pick the same owning module when we start instantiating a template that
we'll later pick when determining which modules are visible during that
instantiation.
This reinstates r300650, reverted in r300659, with a fix for a regression
reported by Chandler after commit.
llvm-svn: 300938
modules but exposes much more widespread issues. Example and more
information is on the review thread for r300650.
Original commit summary:
[modules] Properly look up the owning module for an instantiation of a merged template.
llvm-svn: 300659
When looking for the template instantiation pattern of a templated entity,
consistently select the definition of the pattern if there is one. This means
we'll pick the same owning module when we start instantiating a template that
we'll later pick when determining which modules are visible during that
instantiation.
llvm-svn: 300650
Calculating the hash in Sema::ActOnTagFinishDefinition could happen before
all sub-Decls were parsed or processed, which would produce the wrong hash
value. Change to calculating the hash on the first use and storing the value
instead. Also, avoid using the macros that were only for Boolean fields and
use an explicit checker during the DefintionData merge. No functional change,
but was this blocking other ODRHash patches.
llvm-svn: 299989
Summary: When adding an Objective-C retainable type member to a C++ class, also check the LangOpts.ObjCWeak flag and the lifetime qualifier so __weak qualified Objective-C pointer members cause the class to be a non-POD type with non-trivial special members, so the compiler always emits the necessary runtime calls for copying, moving, and destroying the weak member. Otherwise, Objective-C++ classes with weak Objective-C pointer members compiled with -fobjc-weak exhibit undefined behavior if the C++ class is classified as a POD type.
Reviewers: rsmith, benlangmuir, doug.gregor, rjmccall
Reviewed By: rjmccall
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D31003
llvm-svn: 299008
Essentially, as a base class constructor does not construct virtual bases, such
a constructor for an abstract class does not need the corresponding base class
construction to be valid, and likewise for destructors.
This creates an awkward situation: clang will sometimes generate references to
the complete object and deleting destructors for an abstract class (it puts
them in the construction vtable for a derived class). But we can't generate a
"correct" version of these because we can't generate references to base class
constructors any more (if they're template specializations, say, we might not
have instantiated them and can't assume any other TU will emit a copy).
Fortunately, we don't need to, since no correct program can ever invoke them,
so instead emit symbols that just trap.
We should stop emitting references to these symbols, but still need to emit
definitions for compatibility.
llvm-svn: 296275
Add the basics for the ODRHash class, which will only process Decl's from
a whitelist, which currently only has AccessSpecDecl. Different access
specifiers in merged classes can now be detected.
Differential Revision: https://reviews.llvm.org/D21675
llvm-svn: 295800
Reserve a spot for ODR hash in CXXRecordDecl and in its modules storage.
Default the hash value to 0 for all classes.
Differential Revision: https://reviews.llvm.org/D21675
llvm-svn: 295533
A slightly weaker form of ODR checking than previous attempts, but hopefully
won't break the modules build bot. Future work will be needed to catch all
cases.
When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation. Previously, only a small number of such
violations were detected. This patch provides a stronger check based on
AST nodes.
The information needed to uniquely identify an object is taken from the AST and
put into a one-dimensional byte stream. This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.
When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared. Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.
The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops. For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed. As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.
Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.
Differential Revision: https://reviews.llvm.org/D21675
llvm-svn: 295421
Recommit r293585 that was reverted in r293611 with new fixes. The previous
issue was determined to be an overly aggressive AST visitor from forward
declared objects. The visitor will now only deeply visit certain Decl's and
only do a shallow information extraction from all other Decl's.
When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation. Previously, only a small number of such
violations were detected. This patch provides a stronger check based on
AST nodes.
The information needed to uniquely identify an object is taken from the AST and
put into a one-dimensional byte stream. This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.
When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared. Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.
The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops. For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed. As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.
Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.
Differential Revision: https://reviews.llvm.org/D21675
llvm-svn: 295284
We're seeing what we believe are false positives. (It's hard to tell with the
available diagnostics, and I'm not sure how to reduce them yet).
I'll send Richard reproduction details offline.
djasper/chandlerc suggested this should be a warning for now, to make rolling it
out feasible.
llvm-svn: 293611
When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation. Previously, only a small number of such
violations were detected. This patch provides a stronger check based on
AST nodes.
The information needed to uniquely identify an object is taked from the AST and
put into a one-dimensional byte stream. This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.
When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared. Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.
The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops. For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed. As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.
Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.
Differential Revision: https://reviews.llvm.org/D21675
llvm-svn: 293585
effect they would have in C++11. In particular, they do not prevent
value-initialization from performing zero-initialization, nor do they prevent a
struct from being an aggregate.
llvm-svn: 290229
This change introduces UsingPackDecl as a marker for the set of UsingDecls
produced by pack expansion of a single (unresolved) using declaration. This is
not strictly necessary (we just need to be able to map from the original using
declaration to its expansions somehow), but it's useful to maintain the
invariant that each declaration reference instantiates to refer to one
declaration.
This is a re-commit of r290080 (reverted in r290092) with a fix for a
use-after-lifetime bug.
llvm-svn: 290203
This change introduces UsingPackDecl as a marker for the set of UsingDecls
produced by pack expansion of a single (unresolved) using declaration. This is
not strictly necessary (we just need to be able to map from the original using
declaration to its expansions somehow), but it's useful to maintain the
invariant that each declaration reference instantiates to refer to one
declaration.
llvm-svn: 290080
copy constructors of classes with array members, instead using
ArrayInitLoopExpr to represent the initialization loop.
This exposed a bug in the static analyzer where it was unable to differentiate
between zero-initialized and unknown array values, which has also been fixed
here.
llvm-svn: 289618
Summary:
The C++17 rules for aggregate initialization changed to disallow types with explicit constructors [dcl.init.aggr]p1. This patch implements that new rule.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25654
llvm-svn: 288565
anonymous union member of a class, we need overload resolution for the move
constructor of the class itself too; we can't rely on Sema to do the right
thing for us for anonymous union types.
llvm-svn: 278763
tuple-like decomposition declaration. This significantly simplifies the
semantics of BindingDecls for AST consumers (they can now always be evalated
at the point of use).
llvm-svn: 278640
decomposition declarations.
There are a couple of things in the wording that seem strange here:
decomposition declarations are permitted at namespace scope (which we partially
support here) and they are permitted as the declaration in a template (which we
reject).
llvm-svn: 276492
Replace inheriting constructors implementation with new approach, voted into
C++ last year as a DR against C++11.
Instead of synthesizing a set of derived class constructors for each inherited
base class constructor, we make the constructors of the base class visible to
constructor lookup in the derived class, using the normal rules for
using-declarations.
For constructors, UsingShadowDecl now has a ConstructorUsingShadowDecl derived
class that tracks the requisite additional information. We create shadow
constructors (not found by name lookup) in the derived class to model the
actual initialization, and have a new expression node,
CXXInheritedCtorInitExpr, to model the initialization of a base class from such
a constructor. (This initialization is special because it performs real perfect
forwarding of arguments.)
In cases where argument forwarding is not possible (for inalloca calls,
variadic calls, and calls with callee parameter cleanup), the shadow inheriting
constructor is not emitted and instead we directly emit the initialization code
into the caller of the inherited constructor.
Note that this new model is not perfectly compatible with the old model in some
corner cases. In particular:
* if B inherits a private constructor from A, and C uses that constructor to
construct a B, then we previously required that A befriends B and B
befriends C, but the new rules require A to befriend C directly, and
* if a derived class has its own constructors (and so its implicit default
constructor is suppressed), it may still inherit a default constructor from
a base class
llvm-svn: 274049
This implements support for MS-specific __unaligned qualifier in functions and
makes the following test case both compile and mangle correctly:
struct S {
void f() __unaligned;
};
void S::f() __unaligned {
}
Differential Revision: http://reviews.llvm.org/D20437
llvm-svn: 270834
a base class via a using-declaration. If a class has a using-declaration
declaring either a constructor or an assignment operator, eagerly declare its
special members in case they need to displace a shadow declaration from a
using-declaration.
llvm-svn: 269398
r261297 called hasUserProvidedDefaultConstructor() to check if defining a
const object is ok. This is incorrect for this example:
struct X { template<typename ...T> X(T...); int n; };
const X x; // formerly OK, now bogus error
Instead, track if a class has a defaulted default constructor, and disallow
a const object for classes that either have defaulted default constructors or
if they need an implicit constructor.
Bug report and fix approach by Richard Smith, thanks!
llvm-svn: 261770
For templates, fields can have incomplete types:
template <class T>
struct A2 {
struct B;
B b;
};
Don't try to touch the DefinitionData of those fields.
llvm-svn: 261301
C++11 requires const objects to have a user-provided constructor, even for
classes without any fields. DR 253 relaxes this to say "If the implicit default
constructor initializes all subobjects, no initializer should be required."
clang is currently the only compiler that implements this C++11 rule, and e.g.
libstdc++ relies on something like DR 253 to compile in newer versions. This
change makes it possible to build code that says `const vector<int> v;' again
when using libstdc++5.2 and _GLIBCXX_DEBUG
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60284).
Fixes PR23381.
http://reviews.llvm.org/D16552
llvm-svn: 261297
keys, and PointerIntPairs where the pointee types are incomplete
out-of-line to where we have the complete type.
This is the standard pattern used throughout the AST library to address
the inherently mutually cross referenced nature of the AST.
This is part of a series of patches to allow LLVM to check for complete
pointee types when computing its pointer traits. This is absolutely
necessary to get correct (or reproducible) results for things like how
many low bits are guaranteed to be zero.
llvm-svn: 256612
Hubert Tong