control the visibility of a type for the purposes of RTTI
and template argument restrictions independently of how
visibility propagates to its non-type member declarations.
Also fix r175326 to not ignore template argument visibility
on a template explicit instantiation when a member has
an explicit attribute but the instantiation does not.
The type_visibility work is rdar://11880378
llvm-svn: 175587
We treat this as an alternative to -fvisibility=<?>
which changes the default value visibility to "hidden"
and the default type visibility to "default".
Expose a -cc1 option for changing the default type
visibility, repurposing -fvisibility as the default
value visibility option (also setting type visibility
from it in the absence of a specific option).
rdar://13079314
llvm-svn: 175480
for distinguishing type vs. value visibility.
The changes to the visibility of explicit specializations
are intentional. The change to the "ugly" test case is
a consequence of a sensible implementation, and I am happy
to argue that this is better behavior. Other changes may
or may not be intended; it is quite difficult to divine
intent from some of the code I altered.
I've left behind a comment which I hope explains the
philosophy behind visibility computation.
llvm-svn: 175326
I added hasCLanguageLinkage while fixing some language linkage bugs some
time ago so that I wouldn't have to check all users of isExternC. It turned
out to be a much longer detour than expected, but this patch finally
merges the two again. The isExternC function now implements just the
standard notion of having C language linkage.
llvm-svn: 175119
some cases where functions with no language linkage were being treated as having
C language linkage. In particular, don't warn in
extern "C" {
static NonPod foo();
}
Since getLanguageLinkage checks the language linkage, the linkage computation
cannot use the language linkage. Break the loop by checking just the context
in the linkage computation.
llvm-svn: 175117
the linkage of functions and variables while merging declarations from modules,
and we don't necessarily have enough of the rest of the AST loaded at that
point to allow us to compute linkage, so serialize it instead.
llvm-svn: 174943
visible.
The basic problem here is that a given translation unit can use
forward declarations to form pointers to a given type, say,
class X;
X *x;
and then import a module that includes a definition of X:
import XDef;
We will then fail when attempting to access a member of X, e.g.,
x->method()
because the AST reader did not know to look for a default of a class
named X within the new module.
This implementation is a bit of a C-centric hack, because the only
definitions that can have this property are enums, structs, unions,
Objective-C classes, and Objective-C protocols, and all of those are
either visible at the top-level or can't be defined later. Hence, we
can use the out-of-date-ness of the name and the identifier-update
mechanism to force the update.
In C++, we will not be so lucky, and will need a more advanced
solution, because the definitions could be in namespaces defined in
two different modules, e.g.,
// module 1
namespace N { struct X; }
// module 2
namespace N { struct X { /* ... */ }; }
One possible implementation here is for C++ to extend the information
associated with each identifier table to include the declaration IDs
of any definitions associated with that name, regardless of
context. We would have to eagerly load those definitions.
llvm-svn: 174794
Title: [PR9027] volatile struct bug: member is not loaded at -O;
This is caused by last flag passed to @llvm.memcpy being false,
not honoring that aggregate has at least one 'volatile' data member
(even though aggregate itself has not been qualified as 'volatile'.
As a result, optimization optimizes away the memcpy altogether.
Patch review by John MaCall (I still need to fix up a test though).
llvm-svn: 173535
for template instantiations, and use it to simplify the implementation of
FunctionDecl::isInlined().
This incidentally changes the result of isInlined on a declared-but-not-defined
non-inline member function from true to false. This is sort of a bug fix, but
currently isInlined is only called on function definitions, so it has no visible
effects.
llvm-svn: 173397
it apart from [[gnu::noreturn]] / __attribute__((noreturn)), since their
semantics are not equivalent (for instance, we treat [[gnu::noreturn]] as
affecting the function type, whereas [[noreturn]] does not).
llvm-svn: 172691
The testcase in pr14929 shows that this is extremely hard to do. If we choose
to apply the attribute, that causes the visibility of some decls to change and
that can happen really late (during codegen).
Current gcc warns and ignores the attribute in this testcase with a warning.
This suggest that the correct solution is to find a point in the compilation
where we can compute the visibility and
* assert it was never computed before
* reject any attempts to compute it again in the future (with warnings).
llvm-svn: 172305
It is somewhat hard to test linkage, so I decided to try to add an assert. This
already found some interesting cases where there were different.
llvm-svn: 171585
This patch moves hasCLanguageLinkage to be VarDecl and FunctionDecl methods
so that they can be used from SemaOverload.cpp and then fixes the logic
in Sema::IsOverload.
llvm-svn: 171193
the body of a functions. The problem was that hasBody looks at the entire chain
and causes problems to -fvisibility-inlines-hidden if the cache was not
invalidated.
Original message:
Cache visibility of decls.
This unifies the linkage and visibility caching. I first implemented this when
working on pr13844, but the previous fixes removed the performance advantage of
this one.
This is still a step in the right direction for making linkage and visibility
cheap to use.
llvm-svn: 171053
This unifies the linkage and visibility caching. I first implemented this when
working on pr13844, but the previous fixes removed the performance advantage of
this one.
This is still a step in the right direction for making linkage and visibility
cheap to use.
llvm-svn: 171048
This fixes the storage class of extern decls that are merged with file level
statics. The patch also fixes the linkage computation so that they are
considered internal.
llvm-svn: 170406
Remove pre-standard restriction on explicitly-defaulted copy constructors with
'incorrect' parameter types, and instead just make those special members
non-trivial as the standard requires.
This required making CXXRecordDecl correctly handle classes which have both a
trivial and a non-trivial special member of the same kind.
This also fixes PR13217 by reimplementing DiagnoseNontrivial in terms of the
new triviality computation technology.
llvm-svn: 169667
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
This corrects the mangling and linkage of classes (& their member functions) in
cases like this:
struct foo {
struct {
void func() { ... }
} x;
};
we were accidentally giving this nested unnamed struct 'no' linkage where it
should've had the linkage of the outer class. The mangling was incorrecty too,
mangling as TU-wide unnamed type mangling of $_X rather than class-scoped
mangling of UtX_.
This also fixes -Wunused-member-function which would incorrectly diagnose
'func' as unused due to it having no linkage & thus appearing to be TU-local
when in fact it might be correctly used in another TU.
Similar mangling should be applied to function local classes in similar cases
but I've deferred that for a subsequent patch.
Review/discussion by Richard Smith, John McCall, & especially Eli Friedman.
llvm-svn: 167906
attributes. In cases where the merged declaration is fully equivalent to the
two original ones, some of the code was getLVForDecl was duplicated.
Cases that are still handled in getLVForDecl are things like
__private_extern__ int N;
int N;
For which we cannot produce a single merged decl with all the information.
llvm-svn: 167703
of the initializer is valid before using it.
Fixes rdar://12455002&12449015 where local variables of objc objects in ARC mode
were not annotated because of the ImplicitValueInitExpr initializer having invalid
source range, resulting in the SourceRange of the VarDecl having invalid end location.
llvm-svn: 165456
enough information so we can mangle them correctly in cases involving
dependent parameter types. (This specifically impacts cases involving
null pointers and cases involving parameters of reference type.)
Fix the mangler to use this information instead of trying to scavenge
it out of the parameter declaration.
<rdar://problem/12296776>.
llvm-svn: 164656
load in the IndirectField declarations as well.
Field designators in initializer lists depend on traversing the fields
decl chain to find the indirect fields.
Fixes rdar://12239321
llvm-svn: 163552
only using the linkage.
Use and test both, documenting that considering the visibility and linkage
of template parameters is a difference from gcc.
llvm-svn: 158309
constexpr until we get to the end of the class definition. When that happens,
be sure to remember that the class actually does have a constexpr constructor.
This is a stopgap solution, which still doesn't cover the case of a class with
multiple copy constructors (only some of which are constexpr). We should be
performing constructor lookup when implicitly defining a constructor in order
to determine whether all constructors it invokes are constexpr.
llvm-svn: 158228
In addition, I've made the pointer and reference typedef 'void' rather than T*
just so they can't get misused. I would've omitted them entirely but
std::distance likes them to be there even if it doesn't use them.
This rolls back r155808 and r155869.
Review by Doug Gregor incorporating feedback from Chandler Carruth.
llvm-svn: 158104
struct HIDDEN foo {
};
template <class P>
struct bar {
};
template <>
struct HIDDEN bar<foo> {
DEFAULT static void zed();
};
void bar<foo>::zed() {
}
Before we would produce a hidden symbol in
struct HIDDEN foo {
};
template <class P>
struct bar {
};
template <>
struct bar<foo> {
DEFAULT static void zed();
};
void bar<foo>::zed() {
}
But adding HIDDEN to the specialization would cause us to produce a default
symbol.
llvm-svn: 157206
* Don't copy the visibility attribute during instantiations. We have to be able
to distinguish
struct HIDDEN foo {};
template<class T>
DEFAULT void bar() {}
template DEFAULT void bar<foo>();
from
struct HIDDEN foo {};
template<class T>
DEFAULT void bar() {}
template void bar<foo>();
* If an instantiation has an attribute, it takes precedence over an attribute
in the template.
* With instantiation attributes handled with the above logic, we can now
select the minimum visibility when looking at template arguments.
llvm-svn: 156821
filter_decl_iterator had a weird mismatch where both op* and op-> returned T*
making it difficult to generalize this filtering behavior into a reusable
library of any kind.
This change errs on the side of value, making op-> return T* and op* return
T&.
(reviewed by Richard Smith)
llvm-svn: 155808
the tempale arguments in deciding the visibility.
This agrees with gcc 4.7.
Found by trying to build chrome with component=shared_library with 155314
reverted.
llvm-svn: 155316
This fixes the included testcase and lets us simplify the code a bit. It
does require using mergeWithMin when merging class information to its
members. Expand the comments to explain why that works.
llvm-svn: 155103
there is no need for mergeVisibily to ever increase the visibility. Not
doing so lets us replace an incorrect use of mergeVisibilityWithMin. The
testcase
struct HIDDEN RECT {
int top;
};
DEFAULT RECT foo = {0};
shows that we should give preference to one of the attributes instead of
keeping the minimum. We still get this testcase wrong because mergeVisibily
handles two explicit visibilities incorrectly, but this is a step in the
right direction.
llvm-svn: 155101
the current implementation this should be a nop as explicit visibility
takes precedence in mergeVisibility.
The location chosen is such that attributes checked above it can force
a symbol to be default. For example, an attribute is the variable or function.
Attributes checked after this point, can only make the visibility more
restrictive. An attribute in a type for example.
llvm-svn: 155098
currently a nop as those users are the first merge or are a merge
of a hidden explicit visibility, which always wins in the current
implementation.
llvm-svn: 155095
search for the specialization (in a folding set) and, if not found
form a *Decl that is then inserted into that folding set. In rare
cases, the folding set may be reallocated between the search and the
insertion, causing a crash. No test case, because triggering rehashing
consistently in a small test case is not feasible. Fixes
<rdar://problem/11115071>.
llvm-svn: 153575
completion item. For example, if the code completion itself represents
a declaration in a namespace (say, std::vector), then this API
retrieves the cursor kind and name of the namespace (std). Implements
<rdar://problem/11121951>.
llvm-svn: 153545
scoped enumeration members. Later uses of an enumeration temploid as a nested
name specifier should cause its instantiation. Plus some groundwork for
explicit specialization of member enumerations of class templates.
llvm-svn: 152750
- This function is not at all free; pass it around along some hot paths instead
of recomputing it deep inside various VarDecl methods.
llvm-svn: 152363
early, since their values can be used in constant expressions in C++11. For
odr-use checking, the opposite change is required, since references are
odr-used whether or not they satisfy the requirements for appearing in a
constant expression.
llvm-svn: 151881
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
* Handle some situations where we should never make a decl more visible,
even when merging in an explicit visibility.
* Handle attributes in members of classes that are explicitly specialized.
Thanks Nico for the report and testing, Eric for the initial review, and dgregor
for the awesome test27 :-)
llvm-svn: 151236
stable mangling, since these lambdas can end up in multiple
translation units. Sema is responsible for deciding when this is the
case, because it's already responsible for choosing the mangling
number.
llvm-svn: 151029
This seems to negatively affect compile time onsome ObjC tests
(which use a lot of partial diagnostics I assume). I have to come
up with a way to keep them inline without including Diagnostic.h
everywhere. Now adding a new diagnostic requires a full rebuild
of e.g. the static analyzer which doesn't even use those diagnostics.
This reverts commit 6496bd10dc3a6d5e3266348f08b6e35f8184bc99.
This reverts commit 7af19b817ba964ac560b50c1ed6183235f699789.
This reverts commit fdd15602a42bbe26185978ef1e17019f6d969aa7.
This reverts commit 00bd44d5677783527d7517c1ffe45e4d75a0f56f.
This reverts commit ef9b60ffed980864a8db26ad30344be429e58ff5.
llvm-svn: 150006
Fix all the files that depended on transitive includes of Diagnostic.h.
With this patch in place changing a diagnostic no longer requires a full rebuild of the StaticAnalyzer.
llvm-svn: 149781
argument in strncat.
The warning is ignored by default since it needs more qualification.
TODO: The warning message and the note are messy when
strncat is a builtin due to the macro expansion.
llvm-svn: 149524
for FunctionDecl::getMemoryFunctionKind().
This is a follow up on the Chris's review for r148142: We don't want to
pollute FunctionDecl with an extra enum. (To make this work, added
memcmp and family to the library builtins.)
llvm-svn: 148267
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
APValue::Array and APValue::MemberPointer. All APValue values can now be emitted
as constants.
Add new CGCXXABI entry point for emitting an APValue MemberPointer. The other
entrypoints dealing with constant member pointers are no longer necessary and
will be removed in a later change.
Switch codegen from using EvaluateAsRValue/EvaluateAsLValue to
VarDecl::evaluateValue. This performs caching and deals with the nasty cases in
C++11 where a non-const object's initializer can refer indirectly to
previously-initialized fields within the same object.
Building the intermediate APValue object incurs a measurable performance hit on
pathological testcases with huge initializer lists, so we continue to build IR
directly from the Expr nodes for array and record types outside of C++11.
llvm-svn: 148178
With that, centralize the way we merge visibility, always preferring explicit over
implicit and then picking the most restrictive one.
Fixes pr10113 and pr11690.
llvm-svn: 148163
the AST reader doesn't actually perform a merge, because name lookup
knows how to merge identical typedefs together.
As part of this, teach C/Objective-C name lookup to return multiple
results in all cases, rather than first digging through the attributes
to see if the value is overloadable. This way, we'll catch ambiguous
lookups in C/Objective-C.
llvm-svn: 147498
variable is initialized by a non-constant expression, and pass in the variable
being declared so that earlier-initialized fields' values can be used.
Rearrange VarDecl init evaluation to make this possible, and in so doing fix a
long-standing issue in our C++ constant expression handling, where we would
mishandle cases like:
extern const int a;
const int n = a;
const int a = 5;
int arr[n];
Here, n is not initialized by a constant expression, so can't be used in an ICE,
even though the initialization expression would be an ICE if it appeared later
in the TU. This requires computing whether the initializer is an ICE eagerly,
and saving that information in PCH files.
llvm-svn: 146856
explicit template specializations (which represent actual functions somebody wrote).
Along the way, refactor some other code which similarly cares about whether or
not they are looking at a template instantiation.
llvm-svn: 145547
- Remodel Expr::EvaluateAsInt to behave like the other EvaluateAs* functions,
and add Expr::EvaluateKnownConstInt to capture the current fold-or-assert
behaviour.
- Factor out evaluation of bitfield bit widths.
- Fix a few places which would evaluate an expression twice: once to determine
whether it is a constant expression, then again to get the value.
llvm-svn: 141561
the fields if they are already loaded, just ignore them when we are building
the chain in BuildDeclChain.
This fixes an lldb issue where fields were removed and not getting re-added
because lldb is based on ASTImporter adding decls to DeclContext and fields
were already added before by the ASTImporter.
We should really simplify the interaction between DeclContext <-> lldb
going forward..
rdar://10246067
llvm-svn: 141418
builtin types (When requested). This is another step toward making
ASTUnit build the ASTContext as needed when loading an AST file,
rather than doing so after the fact. No actual functionality change (yet).
llvm-svn: 138985
Example:
template <class T>
class A {
public:
template <class U> void f(U p) { }
template <> void f(int p) { } // <== class scope specialization
};
This extension is necessary to parse MSVC standard C++ headers, MFC and ATL code.
BTW, with this feature in, clang can parse (-fsyntax-only) all the MSVC 2010 standard header files without any error.
llvm-svn: 137573
broken because the end location of the parameter was the end location of the default arg,
resulting in a source range that could begin in one file and end in another.
llvm-svn: 136572
to allow clients to specify that they've already (correctly) loaded
declarations, and that no further action is needed.
Also, make sure that we clear the "has external lexical declarations"
bit before calling FindExternalLexicalDecls(), to avoid infinite
recursion.
llvm-svn: 135306
MaterializeTemporaryExpr captures a reference binding to a temporary
value, making explicit that the temporary value (a prvalue) needs to
be materialized into memory so that its address can be used. The
intended AST invariant here is that a reference will always bind to a
glvalue, and MaterializeTemporaryExpr will be used to convert prvalues
into glvalues for that binding to happen. For example, given
const int& r = 1.0;
The initializer of "r" will be a MaterializeTemporaryExpr whose
subexpression is an implicit conversion from the double literal "1.0"
to an integer value.
IR generation benefits most from this new node, since it was
previously guessing (badly) when to materialize temporaries for the
purposes of reference binding. There are likely more refactoring and
cleanups we could perform there, but the introduction of
MaterializeTemporaryExpr fixes PR9565, a case where IR generation
would effectively bind a const reference directly to a bitfield in a
struct. Addresses <rdar://problem/9552231>.
llvm-svn: 133521
The general out-of-line case (including explicit instantiation mostly
works except that the definition is being lost somewhere between the AST
and CodeGen, so the definition is never emitted.
llvm-svn: 131933
placement allocation or deallocation functions. These functions cannot be
replaced by the user and are exempt from the normal requirements on
allocation functions (e.g. that they must return unaliased memory).
llvm-svn: 131386
that the destructor body is trivial and that all member variables also have either
trivial destructors or trivial destructor bodies, we don't need to initialize the
vtable pointers since no virtual member functions will be called on the destructor.
Fixes PR9181.
llvm-svn: 131368
- New isDefined() function checks for deletedness
- isThisDeclarationADefinition checks for deletedness
- New doesThisDeclarationHaveABody() does what
isThisDeclarationADefinition() used to do
- The IsDeleted bit is not propagated across redeclarations
- isDeleted() now checks the canoncial declaration
- New isDeletedAsWritten() does what it says on the tin.
- isUserProvided() now correct (thanks Richard!)
This fixes the bug that we weren't catching
void foo() = delete;
void foo() {}
as being a redefinition.
llvm-svn: 131013
platform implies default visibility. To achieve these, refactor our
lookup of explicit visibility so that we search for both an explicit
VisibilityAttr and an appropriate AvailabilityAttr, favoring the
VisibilityAttr if it is present.
llvm-svn: 128336
computing for a nested decl with explicit visibility. This is all part
of the general philosophy of explicit visibility attributes, where
any information that was obviously available at the attribute site
should probably be ignored. Fixes PR9371.
llvm-svn: 126992
UnresolvedUsingValueDecl to use NestedNameSpecifierLoc rather than the
extremely-lossy NestedNameSpecifier/SourceRange pair it used to use,
improving source-location information.
Various infrastructure updates to support NestedNameSpecifierLoc:
- AST/PCH (de-)serialization
- Recursive AST visitor
- libclang traversal (including the first tests of this
functionality)
llvm-svn: 126459
I tried to add test cases for these, but I can't because variables
aren't warned on the way functions are and the codegen layer appears to
use different logic for determining that 'a' and 'g' in the test case
should receive C mangling. I've included the test so that if we ever
switch the codegen layer to use these functions, we won't regress due to
latent bugs.
llvm-svn: 126453
lead to a serious slowdown (4%) on parsing of Cocoa.h. This memory
optimization should be revisited later, when we have time to look at
the generated code.
llvm-svn: 126033
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
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
linkage into Decl.cpp. Disable this logic for extern "C" functions, because
the operative rule there is weaker. Fixes rdar://problem/8898466
llvm-svn: 125268
- BlockDeclRefExprs always store VarDecls
- BDREs no longer store copy expressions
- BlockDecls now store a list of captured variables, information about
how they're captured, and a copy expression if necessary
With that in hand, change IR generation to use the captures data in
blocks instead of walking the block independently.
Additionally, optimize block layout by emitting fields in descending
alignment order, with a heuristic for filling in words when alignment
of the end of the block header is insufficient for the most aligned
field.
llvm-svn: 125005
a pack expansion, e.g., the parameter pack Values in:
template<typename ...Types>
struct Outer {
template<Types ...Values>
struct Inner;
};
This new implementation approach introduces the notion of an
"expanded" non-type template parameter pack, for which we have already
expanded the types of the parameter pack (to, say, "int*, float*",
for Outer<int*, float*>) but have not yet expanded the values. Aside
from creating these expanded non-type template parameter packs, this
patch updates template argument checking and non-type template
parameter pack instantiation to make use of the appropriate types in
the parameter pack.
llvm-svn: 123845
sentence of [temp.deduct.call]p1, both of which concern the
non-deducibility of parameter packs not at the end of a
parameter-type-list. The latter isn't fully implemented yet; see the
new FIXME.
llvm-svn: 123210
template whose last parameter is a parameter pack. This allows us to
form a call to, e.g.,
template<typename ...Args1, typename ...Args2>
void f(std::pair<Args1, Args2> ...pairs);
given zero or more instances of "pair".
llvm-svn: 122973
parameter packs, along with ParmVarDecl::isParameterPack(), which
looks for function parameter packs. Use these routines to fix some
obvious FIXMEs.
llvm-svn: 122904
expansions with something that is easier to use correctly: a new
template argment kind, rather than a bit on an existing kind. Update
all of the switch statements that deal with template arguments, fixing
a few latent bugs in the process. I"m happy with this representation,
now.
And, oh look! Template instantiation and deduction work for template
template argument pack expansions.
llvm-svn: 122896
Previously designated anonymous fields were found via name lookup. This redesign uses the fact that an IndirectFieldDecl declaration will always follow an anonymous implicit field to remove the special case of name lookup.
llvm-svn: 122387
visibility. Fixes PR8713.
I've disabled a test which was testing that you can #pragma pop visibility
to get out of a namespace's visibility attribute. We should probably just
diagnose that as an error unless it's instrumental to someone's system
headers.
llvm-svn: 121459
"inline", we weren't giving the definition weak linkage because the
"inline" bit wasn't propagated. This was a longstanding FIXME that,
somehow, hadn't triggered a bug in the wild. Fix this problem by
tracking whether any declaration was marked "inline", and clean up the
semantics of GNU's "extern inline" semantics calculation based on this
change.
Fixes <rdar://problem/8740363>.
llvm-svn: 121373
My previous attempt at solving the compile-time problem with many
redeclarations of the same entity cached both linkage and visibility,
while this patch only tackles linkage. There are several reasons for
this difference:
- Linkage is a language concept, and is evaluated many times during
semantic analysis and codegen, while visibility is only a
code-generation concept that is evaluated only once per (unique)
declaration. Hence, we *must* optimize linkage calculations but
don't need to optimize visibility computation.
- Once we know the linkage of a declaration, subsequent
redeclarations can't change that linkage. Hence, cache
invalidation is far simpler than for visibility, where a later
redeclaration can completely change the visibility.
- We have 3 spare bits in Decl to store the linkage cache, so the
cache doesn't increase the size of declarations. With the
visibility+linkage cache, NamedDecl got larger.
llvm-svn: 121023
and visibility of declarations, because it was extremely messy and it
increased the size of NamedDecl.
An improved implementation is forthcoming.
llvm-svn: 121012
declarations.
The motivation for this patch is that linkage/visibility computations
are linear in the number of redeclarations of an entity, and we've run
into a case where a single translation unit has > 6500 redeclarations
of the same (unused!) external variable. Since each redeclaration
involves a linkage check, the resulting quadratic behavior makes Clang
slow to a crawl. With this change, a simple test with 512
redeclarations of a variable syntax-checks ~20x faster than
before.
That said, I hate this change, and will probably end up reverting it
in a few hours. Reasons to hate it:
- It makes NamedDecl larger, since we don't have enough free bits in
Decl to squeeze in the extra information about caching.
- There are way too many places where we need to invalidate this
cache, because the visibility of a declaration can change due to
redeclarations (!). Despite self-hosting and passing the testsuite,
I have no confidence that I've found all of places where this cache
needs to be invalidated.
llvm-svn: 120808
A new AST node is introduced:
def IndirectField : DDecl<Value>;
IndirectFields are injected into the anonymous's parent scope and chain back to
the original field. Name lookup for anonymous entities now result in an
IndirectFieldDecl instead of a FieldDecl.
There is no functionality change, the code generated should be the same.
llvm-svn: 119919
abstractions (e.g., TemplateArgumentListBuilder) that were designed to
support variadic templates. Only a few remnants of variadic templates
remain, in the parser (parsing template type parameter packs), AST
(template type parameter pack bits and TemplateArgument::Pack), and
Sema; these are expected to be used in a future implementation of
variadic templates.
But don't get too excited about that happening now.
llvm-svn: 118385
with their own explicit visibility attributes. Basically we only want to
apply a single visibility attribute from any particular ancestry.
llvm-svn: 117998
independently of whether they're definitions, then teach IR generation to
ignore non-explicit visibility when emitting declarations. Use this to
make sure that RTTI, vtables, and VTTs get the right visibility.
More of rdar://problem/8613093
llvm-svn: 117781
whether it's a declaration or not, then ignores that information for
declarations unless it was explicitly given. It's not totally clear
how that should be mapped into a sane system, but make an effort.
llvm-svn: 117780
for namespace-scope variable declarations.
Apply visibility in IR gen to variables that are merely declared
and never defined. We were previously emitting these with default
visibility unless they were declared with private_extern.
Ignore global visibility settings when computing visibility for
a declaration's context, and key several conditions on whether a
visibility attribute exists anywhere in the hierarchy as opposed
to whether it exists at the current level.
llvm-svn: 117729