Commit Graph

2594 Commits

Author SHA1 Message Date
Richard Smith 434bc3478f PR12298 et al: don't recursively instantiate a template specialization from
within the instantiation of that same specialization. This could previously
happen for eagerly-instantiated function templates, variable templates,
exception specifications, default arguments, and a handful of other cases.

We still have an issue here for default template arguments that recursively
make use of themselves and likewise for substitution into the type of a
non-type template parameter, but in those cases we're producing a different
entity each time, so they should instead be caught by the instantiation depth
limit. However, currently we will typically run out of stack before we reach
it. :(


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@280190 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-31 02:15:21 +00:00
Richard Smith d605534140 C++ Modules TS: add frontend support for building pcm files from module
interface files. At the moment, all declarations (and no macros) are exported,
and 'export' declarations are not supported yet.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@279794 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-26 00:14:38 +00:00
Richard Smith 584334cb10 Fix regression introduced by r279164: only pass definitions as the PatternDef
to DiagnoseUninstantiableTemplate, teach hasVisibleDefinition to correctly
determine whether a function definition is visible, and mark both the function
and the template as visible when merging function template definitions to
provide hasVisibleDefinition with the relevant information.

The change to always pass the right declaration as the PatternDef to
DiagnoseUninstantiableTemplate also caused those checks to happen before other
diagnostics in InstantiateFunctionDefinition, giving worse diagnostics for the
same situations, so I sunk the relevant diagnostics into
DiagnoseUninstantiableTemplate. Those parts of this patch are based on changes
in reviews.llvm.org/D23492 by Vassil Vassilev.


This reinstates r279486, reverted in r279500, with a fix to
DiagnoseUninstantiableTemplate to only mark uninstantiable explicit
instantiation declarations as invalid if we actually diagnosed them. (When we
trigger an explicit instantiation of a class member from an explicit
instantiation declaration for the class, it's OK if there is no corresponding
definition and we certainly don't want to mark the member invalid in that
case.) This previously caused a build failure during bootstrap.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@279557 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-23 19:41:39 +00:00
Chandler Carruth 36fa4bbf3f Revert r279486 "Fix regression introduced by r279164"
Build bots seem unhappy and as Richard was leaving he asked me to revert
this for him. Doing so.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@279500 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-23 02:00:51 +00:00
Richard Smith e7c9a6c34c Fix regression introduced by r279164: only pass definitions as the PatternDef
to DiagnoseUninstantiableTemplate, teach hasVisibleDefinition to correctly
determine whether a function definition is visible, and mark both the function
and the template as visible when merging function template definitions to
provide hasVisibleDefinition with the relevant information.

The change to always pass the right declaration as the PatternDef to
DiagnoseUninstantiableTemplate also caused those checks to happen before other
diagnostics in InstantiateFunctionDefinition, giving worse diagnostics for the
same situations, so I sunk the relevant diagnostics into
DiagnoseUninstantiableTemplate. Those parts of this patch are based on changes
in reviews.llvm.org/D23492 by Vassil Vassilev.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@279486 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-22 22:25:03 +00:00
Richard Smith f76493a344 C++ Modules TS: support parsing the 'module' declaration (including extensions
from p0273r0 approved by EWG). We'll eventually need to handle this from the
lexer as well, in order to disallow preprocessor directives preceding the
module declaration and to support macro import.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@279196 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-19 01:43:06 +00:00
Richard Smith ec9187d1cd C++ Modules TS: Add parsing support for module import declaration.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@279163 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-18 21:59:42 +00:00
Reid Kleckner b2df6a41f4 [MS] Silence -Wextern-init on const selectany variables
In C, 'extern' is typically used to avoid tentative definitions when
declaring variables in headers, but adding an intializer makes it a
defintion. This is somewhat confusing, so GCC and Clang both warn on it.
In C++, 'extern' is often used to give implictly static 'const'
variables external linkage, so don't warn in that case. If selectany is
present, this might be header code intended for C and C++ inclusion, so
apply the C++ rules.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@279116 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-18 18:45:07 +00:00
Erik Pilkington 1d09f0125a [ObjC] Warn on unguarded use of partial declaration
This commit adds a traversal of the AST after Sema of a function that diagnoses
unguarded references to declarations that are partially available (based on
availability attributes). This traversal is only done when we would otherwise
emit -Wpartial-availability.

This commit is part of a feature I proposed here:
http://lists.llvm.org/pipermail/cfe-dev/2016-July/049851.html

Differential revision: https://reviews.llvm.org/D23003

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278826 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-16 17:44:11 +00:00
Richard Smith d28be6c82c P0217R3: template instantiation support for decomposition declarations.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278458 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-12 01:55:21 +00:00
Richard Smith 1068a78bd3 Remove unused and undesirable reference from BindingDecl to DecompositionDecl.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278448 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-12 00:53:41 +00:00
Richard Smith c52f27b275 P0217R3: Constant expression evaluation for decomposition declarations.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278447 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-12 00:39:32 +00:00
Richard Smith 5f0128122c P0217R3: Perform semantic checks and initialization for the bindings in a
decomposition declaration for arrays, aggregate-like structs, tuple-like
types, and (as an extension) for complex and vector types.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278435 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-11 22:25:46 +00:00
Justin Lebar bd12a41e3d [CUDA] Reject calls to __device__ functions from host variable global initializers.
Reviewers: tra

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D23335

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278196 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-10 01:09:21 +00:00
Serge Pavlov c231913835 Pass information in a record instead of stack. NFC
Functions of Sema that work with building of nested name specifiers have too
many parameters (BuildCXXNestedNameSpecifier already expects 10 arguments).
With this change the information about identifier and its context is packed
into a structure, which is then passes to the semantic functions.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@277976 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-08 04:02:15 +00:00
Richard Smith 1a9b9adf6f P0217R3: Parsing support and framework for AST representation of C++1z
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).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@276492 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-22 23:36:59 +00:00
Richard Smith 3b75c09ec6 [modules] Don't emit initializers for VarDecls within a module eagerly whenever
we first touch any part of that module. Instead, defer them until the first
time that module is (transitively) imported. The initializer step for a module
then recursively initializes modules that its own headers imported.

For example, this avoids running the <iostream> global initializer in programs
that don't actually use iostreams, but do use other parts of the standard
library.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@276159 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-20 19:10:16 +00:00
Mehdi Amini 2e23251d3e [NFC] Header cleanup
Summary: Removed unused headers, replaced some headers with forward class declarations

Patch by: Eugene <claprix@yandex.ru>

Differential Revision: https://reviews.llvm.org/D20100

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@275882 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-18 19:02:11 +00:00
Argyrios Kyrtzidis 753944f521 [AST] Keep track of the left brace source location of a tag decl.
This is useful for source modification tools. There will be a follow-up commit using it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@275590 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-15 18:11:33 +00:00
Paul Robinson f6fec8b923 C does not have inline variables.
Add a few missing tests for related C++ diagnostics.

Differential Revision: http://reviews.llvm.org/D22113


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@275493 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-14 22:22:58 +00:00
Yaron Keren 4e226ee7fb Implement FunctionDecl::getDefinition() to be consistent with
VarDecl, TagDecl, EnumDecl, RecordDecl, CXXRecordDecl.

Use getDefinition in two locations to make the code more readable.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@275303 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-13 19:04:51 +00:00
Anastasia Stulova 481ab3b5eb [OpenCL] Improved diagnostics of OpenCL types.
- Changes diagnostics for Blocks to be implicitly
const qualified OpenCL v2.0 s6.12.5.

 - Added and unified diagnostics of some OpenCL special types:
blocks, images, samplers, pipes. These types are intended for use
with the OpenCL builtin functions only and, therefore, most regular
uses are not allowed including assignments, arithmetic operations,
pointer dereferencing, etc.

Review: http://reviews.llvm.org/D21989



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@275061 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-11 13:46:02 +00:00
David Majnemer ce09fec7c1 [AST] Use ArrayRef in more interfaces
ArrayRef is a little better than passing around a pointer/length
pair.

No functional change is intended.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@274732 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-07 04:43:07 +00:00
David Majnemer dab1d243a4 [Sema] A flexible array member must not be the only named member
We didn't correctly detect situations where a flexible array member was
the only named member in a record.

This fixes PR28407.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@274477 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-04 00:24:59 +00:00
Richard Smith 3c1c202ada Implement C++17 P0386R2, inline variables. (The 'inline' specifier gives a
variable weak discardable linkage and partially-ordered initialization, and is
implied for constexpr static data members.)


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@273754 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-25 00:15:56 +00:00
David Majnemer ba5c7ce848 Use more ArrayRefs
No functional change is intended, just a small refactoring.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@273647 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-24 04:05:48 +00:00
Tim Shen a0640f4d99 Re-commit "[Temporary] Add an ExprWithCleanups for each C++ MaterializeTemporaryExpr."
Since D21243 fixes relative clang-tidy tests.

This reverts commit a71d9fbd41.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@273312 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-21 20:29:17 +00:00
Olivier Goffart 12a83d357c Fix a few issues while skipping function bodies
- In functions with try { } catch { }, only the try block would be
   skipped, not the catch blocks

 - The template functions would still be parsed.

 - The initializers within a constructor would still be parsed.

 - The inline functions within class would still be stored, only to be
   discared later.

 - Invalid code with try would assert (as in "int foo() try assert_here")

This attempt to do even less while skipping function bodies.

Differential Revision: http://reviews.llvm.org/D20821

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@272963 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-16 21:40:06 +00:00
Olivier Goffart 21f60bb7d8 Keep invalid functions as part of the AST
Differential Revision: http://reviews.llvm.org/D19764

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@272962 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-16 21:39:55 +00:00
Faisal Vali c306c03ef9 Fix cv-qualification of '*this' captures and nasty bug PR27507
The bug report by Gonzalo (https://llvm.org/bugs/show_bug.cgi?id=27507 -- which results in clang crashing when generic lambdas that capture 'this' are instantiated in contexts where the Functionscopeinfo stack is not in a reliable state - yet getCurrentThisType expects it to be) - unearthed some additional bugs in regards to maintaining proper cv qualification through 'this' when performing by value captures of '*this'.

This patch attempts to correct those bugs and makes the following changes:

   o) when capturing 'this', we do not need to remember the type of 'this' within the LambdaScopeInfo's Capture - it is never really used for a this capture - so remove it.
   o) teach getCurrentThisType to walk the stack of lambdas (even in scenarios where we run out of LambdaScopeInfo's such as when instantiating call operators) looking for by copy captures of '*this' and resetting the type of 'this' based on the constness of that capturing lambda's call operator.

This patch has been baking in review-hell for > 6 weeks - all the comments so far have been addressed and the bug (that it addresses in passing, and I regret not submitting as a separate patch initially) has been reported twice independently, so is frequent and important for us not to just sit on. I merged the cv qualification-fix and the PR-fix initially in one patch, since they resulted from my initial implementation of star-this and so were related. If someone really feels strongly, I can put in the time to revert this - separate the two out - and recommit.  I won't claim it's immunized against all bugs, but I feel confident enough about the fix to land it for now.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@272480 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-11 16:41:54 +00:00
Tim Shen a71d9fbd41 Revert "[Temporary] Add an ExprWithCleanups for each C++ MaterializeTemporaryExpr."
This reverts r272296, since there are clang-tidy failures that appear to
be caused by this change.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@272310 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-09 21:13:39 +00:00
Tim Shen e1fab5f946 [Temporary] Add an ExprWithCleanups for each C++ MaterializeTemporaryExpr.
These ExprWithCleanups are added for holding a RunCleanupsScope not
for destructor calls; rather, they are for lifetime marks. This requires
ExprWithCleanups to keep a bit to indicate whether it have cleanups with
side effects (e.g. dtor calls).

Differential Revision: http://reviews.llvm.org/D20498

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@272296 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-09 19:54:46 +00:00
Manman Ren fca76f6c02 FixIt: use getLocForEndOfToken to insert fix-it after a type name.
Instead of setting DeclSpec's range end to point to the next token
after the DeclSpec, we use getLocForEndOfToken to insert fix-it after a type
name.

Before this fix, fix-it will change
^(NSView view) to ^(*NSView view)

This commit correctly updates the source to ^(NSView* view).

rdar://21042144
Differential Revision: http://reviews.llvm.org/D20844


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@271448 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-02 00:11:03 +00:00
Alexey Bataev c8dc8c5444 [MSVC] Fix stack overflow in unqualified type lookup logic, by Will
Wilson.

An unqualified lookup for in base classes may cause stack overflow if
the base class is a specialization of current class.
Patch by Will Wilson.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@271251 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-31 06:21:27 +00:00
Denis Zobnin 99820de733 [ms][dll] #26935 Defining a dllimport function should cause it to be exported
If we have some function with dllimport attribute and then we have the function
definition in the same module but without dllimport attribute we should add
dllexport attribute to this function definition.
The same should be done for variables.

Example:
struct __declspec(dllimport) C3 {
  ~C3();
};
C3::~C3() {;} // we should export this definition.

Patch by Andrew V. Tischenko

Differential revision: http://reviews.llvm.org/D18953


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@270686 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-25 11:32:42 +00:00
Reid Kleckner 27c10ea3c6 [ms] Allow more unqualified lookup of types in dependent base classes
Summary:
In dependent contexts where we know a type name is required, such as a
new expression, we can recover by forming a DependentNameType.

This generalizes our existing compatibility hack for default arguments
for template type parameters.

Works towards parsing atlctrlw.h, which is PR26748.

Reviewers: avt77, rsmith

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D20500

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@270615 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-24 21:23:54 +00:00
Richard Smith cfc5968efb Fix filtering of prior declarations when checking for a tag redeclaration to
map to the redecl context for both decls, not just one of them, and to properly
check that the decl contexts are equivalent.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@270482 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-23 20:03:04 +00:00
Artem Belevich f365f5e4da [CUDA] Do not allow non-empty destructors for global device-side variables.
According to Cuda Programming guide (v7.5, E2.3.1):
> __device__, __constant__ and __shared__ variables defined in namespace
> scope, that are of class type, cannot have a non-empty constructor or a
> non-empty destructor.

Clang already deals with device-side constructors (see D15305).
This patch enforces similar rules for destructors.

Differential Revision: http://reviews.llvm.org/D20140

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@270108 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-19 20:13:53 +00:00
Vassil Vassilev 334ff89aa7 Teach Sema::MergeFunctionDecl to properly check for an out-of-line definition of a function that is declared as =default in its class definition.
First part of PR27699.

Patch by Cristina Cristescu!

Reviewed by Richard Smith and me.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@269935 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-18 15:14:46 +00:00
Andrey Bokhanko 8ecbed3b1a [MSVC] Implementation of __unaligned as a proper type qualifier
This patch implements __unaligned (MS extension) as a proper type qualifier
(before that, it was implemented as an ignored attribute).

It also fixes PR27367 and PR27666.

Differential Revision: http://reviews.llvm.org/D20103


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@269220 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-11 18:38:21 +00:00
Artem Belevich e0c569d597 [CUDA] Restrict init of local __shared__ variables to empty constructors only.
Allow only empty constructors for local __shared__ variables in a way
identical to restrictions imposed on dynamic initializers for global
variables on device.

Differential Revision: http://reviews.llvm.org/D20039

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@268982 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-09 22:09:56 +00:00
Artem Belevich a93fdcf110 [CUDA] Only __shared__ variables can be static local on device side.
According to CUDA programming guide (v7.5):
> E.2.9.4: Within the body of a device or global function, only
> shared variables may be declared with static storage class.

Differential Revision: http://reviews.llvm.org/D20034

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@268962 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-09 19:36:08 +00:00
Nemanja Ivanovic fa54202263 Enable support for __float128 in Clang and enable it on pertinent platforms
This patch corresponds to reviews:
http://reviews.llvm.org/D15120
http://reviews.llvm.org/D19125

It adds support for the __float128 keyword, literals and target feature to
enable it. Based on the latter of the two aforementioned reviews, this feature
is enabled on Linux on i386/X86 as well as SystemZ.
This is also the second attempt in commiting this feature. The first attempt
did not enable it on required platforms which caused failures when compiling
type_traits with -std=gnu++11.

If you see failures with compiling this header on your platform after this
commit, it is likely that your platform needs to have this feature enabled.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@268898 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-09 08:52:33 +00:00
Manman Ren ae16b820f9 Availability: set location when creating attribute for tvos, watchos.
When inferring availability attributes for tvos, watchos from ios, we
use the same source location and set the implicit bit to true.

So when emitting diagnostics on inferred attributes, we have a source
location.

rdar://25893544


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@268793 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-06 21:04:01 +00:00
Nico Weber 75762ded3b Revert r268727, it caused PR27666.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@268736 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-06 14:34:29 +00:00
Andrey Bokhanko 7fd0aa52a1 [MSVC] Implementation of __unaligned as a proper type qualifier
This patch implements __unaligned (MS extension) as a proper type qualifier
(before that, it was implemented as an ignored attribute).

It also fixes PR27367.

Differential Revision: http://reviews.llvm.org/D19654


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@268727 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-06 11:47:55 +00:00
Aaron Ballman ce6d6c2e99 Add the Pure attribute to C99 builtin functions from ctype.h. This is a corrected version of r266199 with test case fixes.
Patch by Taewook Oh.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@268553 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-04 21:08:13 +00:00
Reid Kleckner e5d643a3e7 Avoid -Wshadow warnings about constructor parameters named after fields
Usually these parameters are used solely to initialize the field in the
initializer list, and there is no real shadowing confusion.

There is a new warning under -Wshadow called
-Wshadow-field-in-constructor-modified. It attempts to find
modifications of such constructor parameters that probably intended to
modify the field.

It has some false negatives, though, so there is another warning group,
-Wshadow-field-in-constructor, which always warns on this special case.
For users who just want the old behavior and don't care about these fine
grained groups, we have a new warning group called -Wshadow-all that
activates everything.

Fixes PR16088.

Reviewers: rsmith

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D18271

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@267957 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-29 00:37:43 +00:00
Faisal Vali fd39f9d7f8 Implement CWG 941 - explicit specializations of deleted function templates
template<class T> void f(T) = delete;
  template<> void f(int); // OK.

  f(3); // OK

Implementation strategy:

When an explicit specialization of a function template, a member function template or a member function of a class template is declared, clang first implicitly instantiates the declaration of a specialization from the templated-entity being explicitly specialized (since their signatures must be the same) and then links the explicit specialization being declared as a redeclaration of the aforementioned specialization.  

The problem was that when clang 'implicitly instantiates' the initial specialization, it marks the corresponding FunctionDecl as deleted if the corresponding templated-entity was deleted, rather than waiting to see whether the explicit specialization being declared provides a non-deleted body. (The eager marking of delete has advantages during overload resolution I suppose, where we don't have to try and instantiate a definition of the function to see if it is deleted). 

The present fix entails recognizing that when clang knows that an explicit specialization is being declared (for whichever templated-entity), the prior implicit instantiation should not inherit the 'deleted' status, and so we reset it to false.

I suppose an alternative fix (amongst others) could consider creating a new context (ExplicitSpecializationDeclarationSubstitution or some such) that is checked during template-argument-deduction and final substitution, and avoid inheriting the deleted status during declaration substitution.  But while conceptually cleaner, that would be a slightly more involved change (as could be some of the other alternatives: such as avoid tagging implicit specializations as deleted, and check their primary templates for the deleted status where needed), and so I chose a different path.  Hopefully it'll prove to not be a bad choice.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@266561 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-17 17:32:04 +00:00
Nemanja Ivanovic c74bb5e707 Revert 266186 as it breaks anything that includes type_traits on some platforms
Since this patch provided support for the __float128 type but disabled it
on all platforms by default, some platforms can't compile type_traits with
-std=gnu++11 since there is a specialization with __float128.
This reverts the patch until D19125 is approved (i.e. we know which platforms
need this support enabled).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@266460 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-15 18:04:13 +00:00