Commit Graph

1955 Commits

Author SHA1 Message Date
Erich Keane 03406c50fa [NFC] Convert ParsedAttr to use llvm::TrailingObjects
ParsedAttr is using a hand-rolled trailing-objects
implementation that gets cleaned up quite a bit by
just using llvm::TrailingObjects. This is a large
TrailingObjects list, but most things are length '0'.

Differential Revision: https://reviews.llvm.org/D50531

llvm-svn: 339380
2018-08-09 20:25:12 +00:00
Erik Pilkington be168a9d34 [Sema] P0961R1: Relaxing the structured bindings customization point finding rules
Differential revision: https://reviews.llvm.org/D50418

llvm-svn: 339375
2018-08-09 20:11:13 +00:00
Eli Friedman 7499610e1b Diagnose invalid cv-qualifiers for friend decls.
Differential Revision: https://reviews.llvm.org/D45712

llvm-svn: 338931
2018-08-03 22:09:44 +00:00
Sanjin Sijaric 56391d6f84 [ARM64] [Windows] Follow MS X86_64 C++ ABI when passing structs
Summary: Microsoft's C++ object model for ARM64 is the same as that for X86_64.
For example, small structs with non-trivial copy constructors or virtual
function tables are passed indirectly.  Currently, they are passed in registers
when compiled with clang.

Reviewers: rnk, mstorsjo, TomTan, haripul, javed.absar

Reviewed By: rnk, mstorsjo

Subscribers: kristof.beyls, chrib, llvm-commits, cfe-commits

Differential Revision: https://reviews.llvm.org/D49770

llvm-svn: 338076
2018-07-26 22:18:28 +00:00
Richard Smith ca975b2f58 Fold dangling-field warning into general initialization lifetime checks.
This reinstates r337627, reverted in r337671, with a fix to correctly
handle the lvalueness of array subscript expressions on pointers.

llvm-svn: 337726
2018-07-23 18:50:26 +00:00
Ilya Biryukov e7cd2c38e8 Revert "Fold dangling-field warning into general initialization lifetime checks."
This reverts commit r337627.
After the change, clang started producing invalid warning on the following code:
    struct foo {
      foo(char *x) : x_(&x[10]) {}
    private:
      char *x_;
    };

1.cpp:2:21: warning: initializing pointer member 'x_' with the stack address of parameter 'x' [-Wdangling-field]

llvm-svn: 337671
2018-07-23 06:32:36 +00:00
Richard Smith 8aacc2cce6 Fold dangling-field warning into general initialization lifetime checks.
llvm-svn: 337627
2018-07-20 22:25:55 +00:00
Erich Keane 7963e8bebb Add support for __declspec(code_seg("segname"))
This patch uses CodeSegAttr to represent __declspec(code_seg) rather than 
building on the existing support for #pragma code_seg.
The code_seg declspec is applied on functions and classes. This attribute 
enables the placement of code into separate named segments, including compiler-
generated codes and template instantiations.

For more information, please see the following:
https://msdn.microsoft.com/en-us/library/dn636922.aspx

This patch fixes the regression for the support for attribute ((section).
746b78de78

Patch by Soumi Manna (Manna)
Differential Revision: https://reviews.llvm.org/D48841

llvm-svn: 337420
2018-07-18 20:04:48 +00:00
Richard Smith d87aab939a Restructure checking for, and warning on, lifetime extension.
This change implements C++ DR1696, which makes initialization of a
reference member of a class from a temporary object ill-formed. The
standard wording here is imprecise, but we interpret it as meaning that
any time a mem-initializer would result in lifetime extension, the
program is ill-formed.

This reinstates r337226, reverted in r337255, with a fix for the
InitializedEntity alignment problem that was breaking ARM buildbots.

llvm-svn: 337329
2018-07-17 22:24:09 +00:00
Florian Hahn 0aa117dd2c Temporarily revert r337226 "Restructure checking for, and warning on, lifetime extension."
This change breaks on ARM because pointers to clang::InitializedEntity are only
4 byte aligned and do not have 3 bits to store values. A possible solution
would be to change the fields in clang::InitializedEntity to enforce a bigger
alignment requirement.

The error message is

llvm/include/llvm/ADT/PointerIntPair.h:132:3: error: static_assert failed "PointerIntPair with integer size too large for pointer"
  static_assert(IntBits <= PtrTraits::NumLowBitsAvailable,
include/llvm/ADT/PointerIntPair.h:73:13: note: in instantiation of template class 'llvm::PointerIntPairInfo<const clang::InitializedEntity *, 3, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *> >' requested here
    Value = Info::updateInt(Info::updatePointer(0, PtrVal),
llvm/include/llvm/ADT/PointerIntPair.h:51:5: note: in instantiation of member function 'llvm::PointerIntPair<const clang::InitializedEntity *, 3, (anonymous namespace)::LifetimeKind, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *>, llvm::PointerIntPairInfo<const clang::InitializedEntity *, 3, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *> > >::setPointerAndInt' requested here
    setPointerAndInt(PtrVal, IntVal);
    ^
llvm/tools/clang/lib/Sema/SemaInit.cpp:6237:12: note: in instantiation of member function 'llvm::PointerIntPair<const clang::InitializedEntity *, 3, (anonymous namespace)::LifetimeKind, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *>, llvm::PointerIntPairInfo<const clang::InitializedEntity *, 3, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *> > >::PointerIntPair' requested here
    return {Entity, LK_Extended};

Full log here:
http://lab.llvm.org:8011/builders/clang-cmake-armv7-global-isel/builds/1330
http://lab.llvm.org:8011/builders/clang-cmake-armv7-full/builds/1394

llvm-svn: 337255
2018-07-17 09:23:31 +00:00
Richard Smith 0a9969b36b Restructure checking for, and warning on, lifetime extension.
This change implements C++ DR1696, which makes initialization of a
reference member of a class from a temporary object ill-formed. The
standard wording here is imprecise, but we interpret it as meaning that
any time a mem-initializer would result in lifetime extension, the
program is ill-formed.

llvm-svn: 337226
2018-07-17 00:11:41 +00:00
Erich Keane e891aa971a [NFC] Rename clang::AttributeList to clang::ParsedAttr
Since The type no longer contains the 'next' item anymore, it isn't a list,
so rename it to ParsedAttr to be more accurate.

llvm-svn: 337005
2018-07-13 15:07:47 +00:00
Erich Keane c480f30580 AttributeList de-listifying:
Basically, "AttributeList" loses all list-like mechanisms, ParsedAttributes is
switched to use a TinyPtrVector (and a ParsedAttributesView is created to
have a non-allocating attributes list). DeclaratorChunk gets the later kind,
Declarator/DeclSpec keep ParsedAttributes.

Iterators are added to the ParsedAttribute types so that for-loops work.

llvm-svn: 336945
2018-07-12 21:09:05 +00:00
Akira Hatanaka 8c21627963 Use cast instead of dyn_cast_or_null.
This addresses John's post-commit review feedback.

https://reviews.llvm.org/rC335021#inline-2038

llvm-svn: 335189
2018-06-20 22:56:59 +00:00
Richard Smith 715ee079da Related to PR37768: improve diagnostics for class name shadowing.
Diagnose the name of the class being shadowed by using declarations, and
improve the diagnostics for the case where the name of the class is
shadowed by a non-static data member in a class with constructors.  In
the latter case, we now always give the "member with the same name as
its class" diagnostic regardless of the relative order of the member and
the constructor, rather than giving an inscrutible diagnostic if the
constructor appears second.

llvm-svn: 335182
2018-06-20 21:58:20 +00:00
Akira Hatanaka ea798aa7f5 [Sema] Produce diagnostics for attribute 'trivial_abi' that appears
after the closing brace of a class declaration.

Merge the two call sites of checkIllFormedTrivialABIStruct and sink it
into CheckCompletedCXXClass so that it is called after the attribute has
been attached to the CXXRecordDecl.

rdar://problem/40873297

llvm-svn: 335021
2018-06-19 05:04:44 +00:00
Sven van Haastregt e6e76fd839 [OpenCL] Support new/delete in Sema
Reject uses of the default new/delete operators with a diagnostic
instead of a crash in OpenCL C++ mode and accept user-defined forms.

Differential Revision: https://reviews.llvm.org/D46651

llvm-svn: 334700
2018-06-14 09:51:54 +00:00
Piotr Padlewski e368de364e Add -fforce-emit-vtables
Summary:
 In many cases we can't devirtualize
 because definition of vtable is not present. Most of the
 time it is caused by inline virtual function not beeing
 emitted. Forcing emitting of vtable adds a reference of these
 inline virtual functions.
 Note that GCC was always doing it.

Reviewers: rjmccall, rsmith, amharc, kuhar

Subscribers: llvm-commits, cfe-commits

Differential Revision: https://reviews.llvm.org/D47108

Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 334600
2018-06-13 13:55:42 +00:00
Craig Topper 7c89d046ea Use SmallPtrSet instead of SmallSet in places where we iterate over the set.
SmallSet forwards to SmallPtrSet for pointer types. SmallPtrSet supports iteration, but a normal SmallSet doesn't. So if it wasn't for the forwarding, this wouldn't work.

These places were found by hiding the begin/end methods in the SmallSet forwarding.

llvm-svn: 334339
2018-06-09 00:30:45 +00:00
Richard Smith e4899c1648 PR37631: verify that a member deduction guide has the same access as its template.
llvm-svn: 333599
2018-05-30 22:13:43 +00:00
Richard Smith fb50dd34ed Revert r332470 (and corresponding tests in r332492).
This regressed our support for __attribute__((section)). See added test file
for example of code broken by this.

llvm-svn: 332760
2018-05-18 20:18:17 +00:00
Erich Keane 64144eb194 Add support for __declspec(code_seg("segname"))
Add support for __declspec(code_seg("segname"))

This patch is built on the existing support for #pragma code_seg. The code_seg
declspec is allowed on functions and classes. The attribute enables the
placement of code into separate named segments, including compiler-generated
members and template instantiations.

For more information, please see the following:
https://msdn.microsoft.com/en-us/library/dn636922.aspx

A new CodeSeg attribute is used instead of adding a new spelling to the existing
Section attribute since they don’t apply to the same Subjects. Section
attributes are also added for the code_seg declspec since they are used for
#pragma code_seg. No CodeSeg attributes are added to the AST.

The patch is written to match with the Microsoft compiler’s behavior even where
that behavior is a little complicated (see https://reviews.llvm.org/D22931, the
Microsoft feedback page is no longer available since MS has removed the page).
That code is in getImplicitSectionAttrFromClass routine.

Diagnostics messages are added to match with the Microsoft compiler for code-seg
attribute mismatches on base and derived classes and virtual overrides.


Differential Revision: https://reviews.llvm.org/D43352

llvm-svn: 332470
2018-05-16 13:57:17 +00:00
Akira Hatanaka 852829792b Address post-commit review comments after r328731. NFC.
- Define a function (canPassInRegisters) that determines whether a
record can be passed in registers based on language rules and
target-specific ABI rules.

- Set flag RecordDecl::ParamDestroyedInCallee to true in MSVC mode and
remove ASTContext::isParamDestroyedInCallee, which is no longer needed.

- Use the same type (unsigned) for RecordDecl's bit-field members.

For more background, see the following discussions that took place on
cfe-commits.

http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180326/223498.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180402/223688.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180409/224754.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180423/226494.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180507/227647.html

llvm-svn: 332397
2018-05-15 21:00:30 +00:00
Reid Kleckner df6dbf6719 Don't propagate dllimport to base class template static data members
MSVC doesn't, so we shouldn't. Fixes PR37232.

llvm-svn: 332074
2018-05-11 01:26:11 +00:00
Adrian Prantl 9fc8faf9e6 Remove \brief commands from doxygen comments.
This is similar to the LLVM change https://reviews.llvm.org/D46290.

We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46320

llvm-svn: 331834
2018-05-09 01:00:01 +00:00
Eric Fiselier 4ed0fe04ef [C++2a] operator<=>: Fix incorrect use of Twine.
llvm-svn: 331713
2018-05-08 02:28:47 +00:00
Eric Fiselier c5fb858053 [C++2a] Implement operator<=>: Address bugs and post-commit review comments after r331677.
This patch addresses some mostly trivial post-commit review comments received
on r331677.

Additionally, this patch fixes an assertion in `getNarrowingKind` caused by
the use of an uninitialized value from `checkThreeWayNarrowingConversion`.

llvm-svn: 331707
2018-05-08 00:52:19 +00:00
Eric Fiselier 0683c0e68d [C++2a] Implement operator<=> CodeGen and ExprConstant
Summary:
This patch tackles long hanging fruit for the builtin operator<=> expressions. It is currently needs some cleanup before landing, but I want to get some initial feedback.

The main changes are:

* Lookup, build, and store the required standard library types and expressions in `ASTContext`. By storing them in ASTContext we don't need to store (and duplicate) the required expressions in the BinaryOperator AST nodes. 

* Implement [expr.spaceship] checking, including diagnosing narrowing conversions. 

* Implement `ExprConstant` for builtin spaceship operators.

* Implement builitin operator<=> support in `CodeGenAgg`. Initially I emitted the required comparisons using `ScalarExprEmitter::VisitBinaryOperator`, but this caused the operand expressions to be emitted once for every required cmp.

* Implement [builtin.over] with modifications to support the intent of P0946R0. See the note on `BuiltinOperatorOverloadBuilder::addThreeWayArithmeticOverloads` for more information about the workaround.




Reviewers: rsmith, aaron.ballman, majnemer, rnk, compnerd, rjmccall

Reviewed By: rjmccall

Subscribers: rjmccall, rsmith, aaron.ballman, junbuml, mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D45476

llvm-svn: 331677
2018-05-07 21:07:10 +00:00
Richard Smith eaf11ad709 Track the result of evaluating a computed noexcept specification on the
FunctionProtoType.

We previously re-evaluated the expression each time we wanted to know whether
the type is noexcept or not. We now evaluate the expression exactly once.

This is not quite "no functional change": it fixes a crasher bug during AST
deserialization where we would try to evaluate the noexcept specification in a
situation where we have not deserialized sufficient portions of the AST to
permit such evaluation.

llvm-svn: 331428
2018-05-03 03:58:32 +00:00
Richard Smith 3a8244df6f Implement P0482R2, support for char8_t type.
This is not yet part of any C++ working draft, and so is controlled by the flag
-fchar8_t rather than a -std= flag. (The GCC implementation is controlled by a
flag with the same name.)

This implementation is experimental, and will be removed or revised
substantially to match the proposal as it makes its way through the C++
committee.

llvm-svn: 331244
2018-05-01 05:02:45 +00:00
Richard Smith b5f8171a1b PR37189 Fix incorrect end source location and spelling for a split '>>' token.
When a '>>' token is split into two '>' tokens (in C++11 onwards), or (as an
extension) when we do the same for other tokens starting with a '>', we can't
just use a location pointing to the first '>' as the location of the split
token, because that would result in our miscomputing the length and spelling
for the token. As a consequence, for example, a refactoring replacing 'A<X>'
with something else would sometimes replace one character too many, and
similarly diagnostics highlighting a template-id source range would highlight
one character too many.

Fix this by creating an expansion range covering the first character of the
'>>' token, whose spelling is '>'. For this to work, we generalize the
expansion range of a macro FileID to be either a token range (the common case)
or a character range (used in this new case).

llvm-svn: 331155
2018-04-30 05:25:48 +00:00
Faisal Vali a534f07f8c Revert rC330794 and some dependent tiny bug fixes
See Richard's humbling feedback here: 
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180423/226482.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180423/226486.html

Wish I'd had the patience to solicit the feedback prior to committing :)

Sorry for the noise guys.

Thank you Richard for being the steward that clang deserves!

llvm-svn: 330888
2018-04-26 00:42:40 +00:00
Faisal Vali 936de9d666 [c++2a] [concepts] Add rudimentary parsing support for template concept declarations
This patch is a tweak of changyu's patch: https://reviews.llvm.org/D40381. It differs in that the recognition of the 'concept' token is moved into the machinery that recognizes declaration-specifiers - this allows us to leverage the attribute handling machinery more seamlessly.

See the test file to get a sense of the basic parsing that this patch supports. 

There is much more work to be done before concepts are usable...

Thanks Changyu!

llvm-svn: 330794
2018-04-25 02:42:26 +00:00
Malcolm Parsons fab3680990 Clean carriage returns from lib/ and include/. NFC.
Summary:
Clean carriage returns from lib/ and include/. NFC.
(I have to make this change locally in order for `git diff` to show sane output after I edit a file, so I might as well ask for it to be committed. I don't have commit privs myself.)
(Without this patch, `git rebase`ing any change involving SemaDeclCXX.cpp is a real nightmare. :( So while I have no right to ask for this to be committed, geez would it make my workflow easier if it were.)

Here's the command I used to reformat things. (Requires bash and OSX/FreeBSD sed.)

    git grep -l $'\r' lib include | xargs sed -i -e $'s/\r//'
    find lib include -name '*-e' -delete

Reviewers: malcolm.parsons

Reviewed By: malcolm.parsons

Subscribers: emaste, krytarowski, cfe-commits

Differential Revision: https://reviews.llvm.org/D45591

Patch by Arthur O'Dwyer.

llvm-svn: 330112
2018-04-16 08:31:08 +00:00
Aaron Ballman 3399e50832 Correctly diagnose when a conversion function is declared with a type qualifier in the declaration specifiers rather than in the conversion type id. Fixes PR30595.
llvm-svn: 329924
2018-04-12 16:41:55 +00:00
Akira Hatanaka e6313ace66 [ObjC++] Never pass structs that transitively contain __weak fields in
registers.

This patch fixes a bug in r328731 that caused structs transitively
containing __weak fields to be passed in registers. The patch replaces
the flag RecordDecl::CanPassInRegisters with a 2-bit enum that indicates
whether the struct or structs containing the struct are forced to be
passed indirectly.

This reapplies r329617. r329617 didn't specify the underlying type for
enum ArgPassingKind, which caused regression tests to fail on a windows
bot.

rdar://problem/39194693

Differential Revision: https://reviews.llvm.org/D45384

llvm-svn: 329635
2018-04-09 22:48:22 +00:00
Akira Hatanaka d236a34ddb Revert "[ObjC++] Never pass structs that transitively contain __weak fields in"
This reverts commit r329617. It broke a windows bot.

http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/16372/steps/test/logs/stdio

llvm-svn: 329627
2018-04-09 21:47:58 +00:00
Akira Hatanaka f15d29ccc7 [ObjC++] Never pass structs that transitively contain __weak fields in
registers.

This patch fixes a bug in r328731 that caused structs transitively
containing __weak fields to be passed in registers. The patch replaces
the flag RecordDecl::CanPassInRegisters with a 2-bit enum that indicates
whether the struct or structs containing the struct are forced to be
passed indirectly.

rdar://problem/39194693

llvm-svn: 329617
2018-04-09 20:39:47 +00:00
Richard Smith 866dee4ea0 Add helper to determine if a field is a zero-length bitfield.
llvm-svn: 328999
2018-04-02 18:29:43 +00:00
Akira Hatanaka fcbe17c6be [ObjC++] Make parameter passing and function return compatible with ObjC
ObjC and ObjC++ pass non-trivial structs in a way that is incompatible
with each other. For example:
    
typedef struct {
  id f0;
  __weak id f1;
} S;
    
// this code is compiled in c++.
extern "C" {
  void foo(S s);
}
    
void caller() {
  // the caller passes the parameter indirectly and destructs it.
  foo(S());
}
    
// this function is compiled in c.
// 'a' is passed directly and is destructed in the callee.
void foo(S a) {
}
    
This patch fixes the incompatibility by passing and returning structs
with __strong or weak fields using the C ABI in C++ mode. __strong and
__weak fields in a struct do not cause the struct to be destructed in
the caller and __strong fields do not cause the struct to be passed
indirectly.
    
Also, this patch fixes the microsoft ABI bug mentioned here:
    
https://reviews.llvm.org/D41039?id=128767#inline-364710
    
rdar://problem/38887866
    
Differential Revision: https://reviews.llvm.org/D44908

llvm-svn: 328731
2018-03-28 21:13:14 +00:00
Richard Trieu b402580616 Fix some handling of AST nodes with diagnostics.
The diagnostic system for Clang can already handle many AST nodes.  Instead
of converting them to strings first, just hand the AST node directly to
the diagnostic system and let it handle the output.  Minor changes in some
diagnostic output.

llvm-svn: 328688
2018-03-28 04:16:13 +00:00
Richard Smith c660c8f5d2 Implement C++ DR727, which permits explicit specializations at class scope.
More generally, this permits a template to be specialized in any scope in which
it could be defined, so this also supersedes DR44 and DR374 (the latter of
which we previously only implemented in C++11 mode onwards due to unclarity as
to whether it was a DR).

llvm-svn: 327705
2018-03-16 13:36:56 +00:00
Stephan Bergmann 0feb0b9059 Propagate DLLAttr to friend re-declarations of member functions
...that have already been constructed (e.g., in inner classes) while parsing the
class definition.  They would otherwise lack any DLLAttr inherited from the
class, which are only set here (called from Sema::CheckCompletedClass) after the
class definition has been parsed completely.

Differential revision: https://reviews.llvm.org/D16632

llvm-svn: 326990
2018-03-08 07:34:40 +00:00
George Burgess IV 00f70bd933 Remove redundant casts. NFC
So I wrote a clang-tidy check to lint out redundant `isa`, `cast`, and
`dyn_cast`s for fun. This is a portion of what it found for clang; I
plan to do similar cleanups in LLVM and other subprojects when I find
time.

Because of the volume of changes, I explicitly avoided making any change
that wasn't highly local and obviously correct to me (e.g. we still have
a number of foo(cast<Bar>(baz)) that I didn't touch, since overloading
is a thing and the cast<Bar> did actually change the type -- just up the
class hierarchy).

I also tried to leave the types we were cast<>ing to somewhere nearby,
in cases where it wasn't locally obvious what we were dealing with
before.

llvm-svn: 326416
2018-03-01 05:43:23 +00:00
Hans Wennborg 83665e6d36 Re-commit r324991 "Fix for PR32992. Static const classes not exported."
Fix for PR32992. Static const classes not exported.

Patch by zahiraam!

(This re-lands the commit, but using S.MarkVariableReferenced instead of
S.PendingInstantiations.push_back, and with an additional test.)

Differential Revision: https://reviews.llvm.org/D42968

llvm-svn: 326089
2018-02-26 15:03:59 +00:00
Hans Wennborg 00f4598ec5 Revert r324991 "Fix for PR32992. Static const classes not exported."
This broke the Chromium build on Windows; see https://crbug.com/812231

> Fix for PR32992. Static const classes not exported.
>
> Patch by zahiraam!
>
> Differential Revision: https://reviews.llvm.org/D42968

llvm-svn: 325133
2018-02-14 15:19:46 +00:00
Hans Wennborg 3bd0a15867 Fix for PR32992. Static const classes not exported.
Patch by zahiraam!

Differential Revision: https://reviews.llvm.org/D42968

llvm-svn: 324991
2018-02-13 09:19:43 +00:00
Akira Hatanaka 02914dc127 Add support for attribute 'trivial_abi'.
The 'trivial_abi' attribute can be applied to a C++ class, struct, or
union. It makes special functions of the annotated class (the destructor
and copy/move constructors) to be trivial for the purpose of calls and,
as a result, enables the annotated class or containing classes to be
passed or returned using the C ABI for the underlying type.

When a type that is considered trivial for the purpose of calls despite
having a non-trivial destructor (which happens only when the class type
or one of its subobjects is a 'trivial_abi' class) is passed to a
function, the callee is responsible for destroying the object.

For more background, see the discussions that took place on the mailing
list:

http://lists.llvm.org/pipermail/cfe-dev/2017-November/055955.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180101/thread.html#214043

rdar://problem/35204524

Differential Revision: https://reviews.llvm.org/D41039

llvm-svn: 324269
2018-02-05 20:23:22 +00:00
Vedant Kumar a14a1f923f [Parse] Forward brace locations to TypeConstructExpr
When parsing C++ type construction expressions with list initialization,
forward the locations of the braces to Sema.

Without these locations, the code coverage pass crashes on the given test
case, because the pass relies on getLocEnd() returning a valid location.

Here is what this patch does in more detail:

  - Forwards init-list brace locations to Sema (ParseExprCXX),
  - Builds an InitializationKind with these locations (SemaExprCXX), and
  - Uses these locations for constructor initialization (SemaInit).

The remaining changes fall out of introducing a new overload for
creating direct-list InitializationKinds.

Testing: check-clang, and a stage2 coverage-enabled build of clang with
asserts enabled.

Differential Revision: https://reviews.llvm.org/D41921

llvm-svn: 322729
2018-01-17 18:53:51 +00:00
Jan Korous fda9daeb03 [Sema] Fix crash for type-dependent base classes
llvm-svn: 322438
2018-01-13 15:24:16 +00:00
Aaron Ballman a503855906 Track in the AST whether the operand to a UnaryOperator can overflow and then use that logic when evaluating constant expressions and emitting codegen.
llvm-svn: 322074
2018-01-09 13:07:03 +00:00
Richard Smith 50e291eaf2 Fix and simplify handling of return type for (generic) lambda conversion function to function pointer.
Previously, we would:
 * compute the type of the conversion function and static invoker as a
   side-effect of template argument deduction for a conversion
 * re-compute the type as part of deduced return type deduction when building
   the conversion function itself

Neither of these turns out to be quite correct. There are other ways to reach a
declaration of the conversion function than in a conversion (such as an
explicit call or friend declaration), and performing auto deduction causes the
function type to be rebuilt in the context of the lambda closure type (which is
different from the context in which it originally appeared, resulting in
spurious substitution failures for constructs that are valid in one context but
not the other, such as the use of an enclosing class's "this" pointer).

This patch switches us to use a different strategy: as before, we use the
declared type of the operator() to form the type of the conversion function and
invoker, but we now populate that type as part of return type deduction for the
conversion function. And the invoker is now treated as simply being an
implementation detail of building the conversion function, and isn't given
special treatment by template argument deduction for the conversion function
any more.

llvm-svn: 321683
2018-01-02 23:52:42 +00:00
Faisal Vali 090da2d1ac Again reverting an attempt to convert the DeclSpec enums into scoped enums.
- reverts r321622, r321625, and r321626.
  - the use of bit-fields is still resulting in warnings - even though we can use static-asserts to harden the code and ensure the bit-fields are wide enough.  The bots still complain of warnings being seen.
  - to silence the warnings requires specifying the bit-fields with the underlying enum type (as opposed to the enum type itself), which then requires lots of unnecessary static casts of each enumerator within DeclSpec to the underlying-type, which even though could be seen as implementation details, it does hamper readability - and given the additional litterings, makes me question the value of the change.

So in short - I give up (for now at least).  

Sorry about the noise.

llvm-svn: 321628
2018-01-01 18:23:28 +00:00
Faisal Vali 038df49033 [NFC] Modernize enums TypeSpecifierWidth, TypeSpecifierSign & TypeSpecifierType into scoped enums with underlying types.
- Since these enums are used as bit-fields - for the bit-fields to be interpreted as unsigned, the underlying type must be specified as unsigned.

Previous failed attempt - wherein I did not specify an underlying type - was the sum of:
https://reviews.llvm.org/rC321614
https://reviews.llvm.org/rC321615

llvm-svn: 321622
2018-01-01 15:42:13 +00:00
Faisal Vali c535adcfc5 Revert r321614 and r321615
- the enum changes to TypeSpecifierType are breaking some tests - and will require a more careful integration.

Sorry about rushing these changes - thought I could sneak them in prior to heading out for new years ;)

llvm-svn: 321616
2018-01-01 02:49:17 +00:00
Faisal Vali 8736dee017 [NFC] Modernize enums TypeSpecifierWidth, TypeSpecifierSign & TypeSpecifierType into scoped enums.
llvm-svn: 321614
2018-01-01 02:19:52 +00:00
Faisal Vali 2ab8c15cf1 [NFC] Modernize enum 'UnqualifiedId::IdKind' into a scoped enum UnqualifiedIdKind.
llvm-svn: 321574
2017-12-30 04:15:27 +00:00
Faisal Vali 421b2d1d8e [NFC] Modernize enum Declarator::TheContext to a type-safe scoped enum.
Note, we don't do any bitwise manipulations when using them.

llvm-svn: 321546
2017-12-29 05:41:00 +00:00
Benjamin Kramer 0742090e3d [AST] Inline CompoundStmt contents into the parent allocation.
Saves a pointer on every CompoundStmt.

llvm-svn: 321429
2017-12-24 16:24:20 +00:00
Adrian Prantl f3b3ccda59 Silence a bunch of implicit fallthrough warnings
llvm-svn: 321115
2017-12-19 22:06:11 +00:00
Benjamin Kramer acfa339e15 Refactor overridden methods iteration to avoid double lookups.
Convert most uses to range-for loops. No functionality change intended.

llvm-svn: 320954
2017-12-17 23:52:45 +00:00
Dimitry Andric c7bc461298 Don't trigger -Wuser-defined-literals for system headers
Summary:
In D41064, I proposed adding `#pragma clang diagnostic ignored
"-Wuser-defined-literals"` to some of libc++'s headers, since these
warnings are now triggered by clang's new `-std=gnu++14` default:

```
$ cat test.cpp
#include <string>

$ clang -std=c++14 -Wsystem-headers -Wall -Wextra -c test.cpp
In file included from test.cpp:1:
In file included from /usr/include/c++/v1/string:470:
/usr/include/c++/v1/string_view:763:29: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string_view<char> operator "" sv(const char *__str, size_t __len)
                            ^
/usr/include/c++/v1/string_view:769:32: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string_view<wchar_t> operator "" sv(const wchar_t *__str, size_t __len)
                               ^
/usr/include/c++/v1/string_view:775:33: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string_view<char16_t> operator "" sv(const char16_t *__str, size_t __len)
                                ^
/usr/include/c++/v1/string_view:781:33: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string_view<char32_t> operator "" sv(const char32_t *__str, size_t __len)
                                ^
In file included from test.cpp:1:
/usr/include/c++/v1/string:4012:24: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string<char> operator "" s( const char *__str, size_t __len )
                       ^
/usr/include/c++/v1/string:4018:27: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string<wchar_t> operator "" s( const wchar_t *__str, size_t __len )
                          ^
/usr/include/c++/v1/string:4024:28: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string<char16_t> operator "" s( const char16_t *__str, size_t __len )
                           ^
/usr/include/c++/v1/string:4030:28: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string<char32_t> operator "" s( const char32_t *__str, size_t __len )
                           ^
8 warnings generated.
```

Both @aaron.ballman and @mclow.lists felt that adding this workaround to
the libc++ headers was the wrong way, and it should be fixed in clang
instead.

Here is a proposal to do just that.  I verified that this suppresses the
warning, even when -Wsystem-headers is used, and that the warning is
still emitted for a declaration outside of system headers.

Reviewers: aaron.ballman, mclow.lists, rsmith

Reviewed By: aaron.ballman

Subscribers: mclow.lists, aaron.ballman, andrew, emaste, cfe-commits

Differential Revision: https://reviews.llvm.org/D41080

llvm-svn: 320755
2017-12-14 22:32:24 +00:00
Zhihao Yuan c81f4538ec Allow conditions to be decomposed with structured bindings
Summary:
This feature was discussed but not yet proposed.  It allows a structured binding to appear as a //condition//

    if (auto [ok, val] = f(...))

So the user can save an extra //condition// if the statement can test the value to-be-decomposed instead.  Formally, it makes the value of the underlying object of the structured binding declaration also the value of a //condition// that is an initialized declaration.

Considering its logicality which is entirely evident from its trivial implementation, I think it might be acceptable to land it as an extension for now before I write the paper.

Reviewers: rsmith, faisalv, aaron.ballman

Reviewed By: rsmith

Subscribers: aaron.ballman, cfe-commits

Differential Revision: https://reviews.llvm.org/D39284

llvm-svn: 320011
2017-12-07 07:03:15 +00:00
Hubert Tong bd72cd9577 Remove old concepts parsing code
Summary:
This is so we can implement concepts per P0734R0. Relevant failing test
cases are disabled.

Reviewers: hubert.reinterpretcast, rsmith, saar.raz, nwilson

Reviewed By: saar.raz

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D40380

Patch by Changyu Li!

llvm-svn: 319992
2017-12-07 00:34:20 +00:00
Aaron Ballman c351fba69e Now that C++17 is official (https://www.iso.org/standard/68564.html), start changing the C++1z terminology over to C++17. NFC intended, these are all mechanical changes.
llvm-svn: 319688
2017-12-04 20:27:34 +00:00
Richard Trieu 7f932dd063 Change assertion to quick exit from checking function.
Remove the assertion that could be triggered by invalid code.  Replace it with
an early exit from the checking function.

llvm-svn: 317073
2017-11-01 03:57:27 +00:00
Reid Kleckner 2e87a21c7c [MS] Allow access to ambiguous, inaccessible direct bases
Summary:
Clang typically warns that in the following class hierarchy, 'A' is
inaccessible because there is no series of casts that the user can
write to access it unambiguously:
  struct A { };
  struct B : A { };
  struct C : A, B { };

MSVC allows the user to convert from C* to A*, though, and we've
encountered this issue in the latest Windows SDK headers.

This patch allows this conversion when -fms-compatibility is set and
adds a warning for it under -Wmicrosoft-inaccessible-base.

Reviewers: rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D39389

llvm-svn: 316807
2017-10-27 22:48:41 +00:00
Richard Smith 5b34958b46 Support for destroying operator delete, per C++2a proposal P0722.
This feature is not (yet) approved by the C++ committee, so this is liable to
be reverted or significantly modified based on committee feedback.

No functionality change intended for existing code (a new type must be defined
in namespace std to take advantage of this feature).

llvm-svn: 315662
2017-10-13 01:55:36 +00:00
Erich Keane 883f22ef7e [Sema][Crash] Correctly handle an non-dependent noexcept expr in function template
It seems that all of the other templated cases are handled correctly,
however the function template case was not correctly handled. This
patch recovers from this condition by setting the function to noexcept
after diagnosing. Previously it simply set NoexceptExpr to null,
which caused an Assert when this was evaluated during substitution.

Differential Revision:https://reviews.llvm.org/D38700

llvm-svn: 315638
2017-10-12 23:01:53 +00:00
Richard Smith becb92dec8 [Modules TS] Module ownership semantics for redeclarations.
When declaring an entity in the "purview" of a module, it's never a
redeclaration of an entity in the purview of a default module or in no module
("in the global module"). Don't consider those other declarations as possible
redeclaration targets if they're not visible, and reject any cases where we
pick a prior visible declaration that violates this rule.

This reinstates r315251 and r315256, reverted in r315309 and r315308
respectively, tweaked to avoid triggering a linkage calculation when declaring
implicit special members (this exposed our pre-existing issue with typedef
names for linkage changing the linkage of types whose linkage has already been
computed and cached in more cases). A testcase for that regression has been
added in r315366.

llvm-svn: 315379
2017-10-10 22:33:17 +00:00
Eric Liu f01516db8d Revert "[Modules TS] Module ownership semantics for redeclarations."
This reverts commit r315251. See the original commit thread for reason.

llvm-svn: 315309
2017-10-10 13:09:40 +00:00
Richard Smith b87720b77a [Modules TS] Module ownership semantics for redeclarations.
When declaring an entity in the "purview" of a module, it's never a
redeclaration of an entity in the purview of a default module or in no module
("in the global module"). Don't consider those other declarations as possible
redeclaration targets if they're not visible, and reject any cases where we
pick a prior visible declaration that violates this rule.

llvm-svn: 315251
2017-10-09 23:42:09 +00:00
Richard Smith 81df9eb0f2 PR33839: Fix -Wunused handling for structured binding declarations.
We warn about a structured binding declaration being unused only if none of its
bindings are used.

llvm-svn: 314733
2017-10-02 22:43:36 +00:00
Erich Keane 97dfc4ab28 [Sema] Correct nothrow inherited by noexcept
As reported in https://bugs.llvm.org/show_bug.cgi?id=33235,
a noexcept function was unable to inherit from a nothrow defaulted
constructor. Attribute "nothrow" is supposed to be semantically
identical to noexcept, and in fact, a number of other places in the
code treat them identically.

This patch simply checks the RecordDecl for the correct attribute in
the case where no other exception specifier was set.

Differential Revision: https://reviews.llvm.org/D38209

llvm-svn: 314462
2017-09-28 20:47:10 +00:00
Nico Weber b688d131f0 Consolidate std::move() detection code. No behavior change.
llvm-svn: 314427
2017-09-28 16:16:39 +00:00
Richard Smith c95d2c5dda Give external linkage and mangling to lambdas inside inline variables and variable templates.
This implements the proposed approach in https://github.com/itanium-cxx-abi/cxx-abi/issues/33

This reinstates r313827, reverted in r313856, with a fix for the 'out-of-bounds
enumeration value' ubsan error in that change.

llvm-svn: 313955
2017-09-22 04:25:05 +00:00
Akira Hatanaka 98a49337be Add support for attribute 'noescape'.
The attribute informs the compiler that the annotated pointer parameter
of a function cannot escape and enables IRGen to attach attribute
'nocapture' to parameters that are annotated with the attribute. That is
the only optimization that currently takes advantage of 'noescape', but
there are other optimizations that will be added later that improves
IRGen for ObjC blocks.

This recommits r313722, which was reverted in r313725 because clang
couldn't build compiler-rt. It failed to build because there were
function declarations that were missing 'noescape'. That has been fixed
in r313929.

rdar://problem/19886775

Differential Revision: https://reviews.llvm.org/D32210

llvm-svn: 313945
2017-09-22 00:41:05 +00:00
Vitaly Buka 17def21749 Revert "Give external linkage and mangling to lambdas inside inline variables and variable templates."
To fix: runtime error: load of value 15, which is not a valid value for type 'clang::LVComputationKind'

This reverts commit r313827.

llvm-svn: 313856
2017-09-21 02:51:56 +00:00
Erich Keane bb8636477d [MS Compat]Allow __interfaces to have properties.
__interface types are allowed in MSVC to have "property" data members
(marked with declspec property). This patch alters Sema to allow property
data members.

Differential Revision: https://reviews.llvm.org/D38092

llvm-svn: 313828
2017-09-20 22:28:24 +00:00
Richard Smith fb130c6084 Give external linkage and mangling to lambdas inside inline variables and variable templates.
This implements the proposed approach in https://github.com/itanium-cxx-abi/cxx-abi/issues/33

llvm-svn: 313827
2017-09-20 22:17:55 +00:00
Akira Hatanaka 30c93dba5b Revert "Add support for attribute 'noescape'."
This reverts commit r313722.

It looks like compiler-rt/lib/tsan/rtl/tsan_libdispatch_mac.cc cannot be
compiled because some of the functions declared in the file do not match
the ones in the SDK headers (which are annotated with 'noescape').

llvm-svn: 313725
2017-09-20 06:55:43 +00:00
Akira Hatanaka e974479fa5 Add support for attribute 'noescape'.
The attribute informs the compiler that the annotated pointer parameter
of a function cannot escape and enables IRGen to attach attribute
'nocapture' to parameters that are annotated with the attribute. That is
the only optimization that currently takes advantage of 'noescape', but
there are other optimizations that will be added later that improves
IRGen for ObjC blocks.

rdar://problem/19886775

Differential Revision: https://reviews.llvm.org/D32210

llvm-svn: 313722
2017-09-20 06:32:45 +00:00
Akira Hatanaka 1b9418e163 Revert "Add support for attribute 'noescape'."
This reverts r313717.

I closed the wrong phabricator review.

llvm-svn: 313721
2017-09-20 06:27:39 +00:00
Akira Hatanaka fc587e6a57 Add support for attribute 'noescape'.
The attribute informs the compiler that the annotated pointer parameter
of a function cannot escape and enables IRGen to attach attribute
'nocapture' to parameters that are annotated with the attribute. That is
the only optimization that currently takes advantage of 'noescape', but
there are other optimizations that will be added later that improves
IRGen for ObjC blocks.

rdar://problem/19886775

Differential Revision: https://reviews.llvm.org/D32520

llvm-svn: 313720
2017-09-20 06:22:51 +00:00
Erich Keane 0ac9524c99 [Sema] Fix a pair of crashes when generating exception specifiers with an
error'ed field for a template class' default ctor.

The two examples in the test would both cause a compiler assert when attempting
to calculate the exception specifier for the default constructor for the
template classes. The problem was that dependents of this function expect that
Field->getInClassInitializer (including canThrow) is not nullptr. However, if
the template's initializer has an error, exactly that situation happens.

This patch simply sets the field to be invalid.

Differential Revision: https://reviews.llvm.org/D37865

llvm-svn: 313569
2017-09-18 21:28:55 +00:00
Erich Keane 58bd603109 Fix the __interface inheritence rules to work better with IUnknown and IDispatch
__interface objects in MSVC are permitted to inherit from __interface types, 
and interface-like types.

Additionally, there are two default interface-like types 
(IUnknown and IDispatch) that all interface-like
types must inherit from.

Differential Revision: https://reviews.llvm.org/D37308

llvm-svn: 313364
2017-09-15 16:03:35 +00:00
Douglas Gregor 672281a511 Diagnostic specific failed condition in a static_assert.
When a static_assert fails, dig out a specific condition to diagnose,
using the same logic that we use to find the enable_if condition to
diagnose.

llvm-svn: 313315
2017-09-14 23:38:42 +00:00
Richard Smith 96cd671cd6 PR19668, PR23034: Fix handling of move constructors and deleted copy
constructors when deciding whether classes should be passed indirectly.

This fixes ABI differences between Clang and GCC:

 * Previously, Clang ignored the move constructor when making this
   determination. It now takes the move constructor into account, per
   https://github.com/itanium-cxx-abi/cxx-abi/pull/17 (this change may
   seem recent, but the ABI change was agreed on the Itanium C++ ABI
   list a long time ago).

 * Previously, Clang's behavior when the copy constructor was deleted
   was unstable -- depending on whether the lazy declaration of the
   copy constructor had been triggered, you might get different behavior.
   We now eagerly declare the copy constructor whenever its deletedness
   is unclear, and ignore deleted copy/move constructors when looking for
   a trivial such constructor.

This also fixes an ABI difference between Clang and MSVC:

 * If the copy constructor would be implicitly deleted (but has not been
   lazily declared yet), for instance because the class has an rvalue
   reference member, we would pass it directly. We now pass such a class
   indirectly, matching MSVC.

Based on a patch by Vassil Vassilev, which was based on a patch by Bernd
Schmidt, which was based on a patch by Reid Kleckner!

This is a re-commit of r310401, which was reverted in r310464 due to ARM
failures (which should now be fixed).

llvm-svn: 310983
2017-08-16 01:49:53 +00:00
Diana Picus 0c9f193acc Revert "PR19668, PR23034: Fix handling of move constructors and deleted copy constructors when deciding whether classes should be passed indirectly."
This reverts commit r310401 because it seems to have broken some ARM
bot(s).

llvm-svn: 310464
2017-08-09 12:22:25 +00:00
Richard Smith f1a425edb7 PR19668, PR23034: Fix handling of move constructors and deleted copy
constructors when deciding whether classes should be passed indirectly.

This fixes ABI differences between Clang and GCC:

 * Previously, Clang ignored the move constructor when making this
   determination. It now takes the move constructor into account, per
   https://github.com/itanium-cxx-abi/cxx-abi/pull/17 (this change may
   seem recent, but the ABI change was agreed on the Itanium C++ ABI
   list a long time ago).

 * Previously, Clang's behavior when the copy constructor was deleted
   was unstable -- depending on whether the lazy declaration of the
   copy constructor had been triggered, you might get different behavior.
   We now eagerly declare the copy constructor whenever its deletedness
   is unclear, and ignore deleted copy/move constructors when looking for
   a trivial such constructor.

This also fixes an ABI difference between Clang and MSVC:

 * If the copy constructor would be implicitly deleted (but has not been
   lazily declared yet), for instance because the class has an rvalue
   reference member, we would pass it directly. We now pass such a class
   indirectly, matching MSVC.

llvm-svn: 310401
2017-08-08 19:12:28 +00:00
Alex Lorenz 99bee7f4a1 Recommit r306103: PR26195: Set correct NestedNameSpecifierLoc for the
dependent initializer

This commit fixes incorrect source positions of dependent c'tor initializers
like in the following code:

template<typename MyBase>
struct Derived: MyBase::InnerIterator
{

Derived() : MyBase::InnerIterator() {} /// This line is problematic: all positions point to InnerIterator and nothing points to MyBase
};

Patch by Serge Preis!

Differential Revision: https://reviews.llvm.org/D32439

llvm-svn: 306392
2017-06-27 10:35:30 +00:00
Akira Hatanaka 12ddceecde [Sema] Fix a crash-on-invalid when a template parameter list has a class
definition or non-reference class type.

The crash occurs when there is a template parameter list in a class that
is missing the closing angle bracket followed by a definition of a
struct. For example:

class C0 {
public:
  template<typename T, typename T1 = T // missing closing angle bracket
  struct S0 {};

  C0() : m(new S0<int>) {}
  S0<int> *m;
};

This happens because the parsed struct is added to the scope of the
enclosing class without having its access specifier set, which results
in an assertion failure in SemaAccess.cpp later.

This commit fixes the crash by adding the parsed struct to the enclosing
file scope and marking structs as invalid if they are defined in
template parameter lists.

rdar://problem/31783961
rdar://problem/19570630

Differential Revision: https://reviews.llvm.org/D33606

llvm-svn: 306317
2017-06-26 18:46:12 +00:00
Alex Lorenz a2af95a615 Revert r306103: "PR26195: Set correct NestedNameSpecifierLoc for the
dependent initializer"

It caused buildbot failures such as this one:
http://bb.pgr.jp/builders/test-clang-msc-x64-on-i686-linux-RA/builds/3777/steps/test_clang/logs/Clang%20%3A%3A%20Index__ctor-init-source-loc.cpp

llvm-svn: 306111
2017-06-23 15:10:54 +00:00
Alex Lorenz 787d30fe18 PR26195: Set correct NestedNameSpecifierLoc for the dependent initializer
This commit fixes incorrect source positions of dependent c'tor initializers
like in the following code:

template<typename MyBase>
struct Derived: MyBase::InnerIterator
{

Derived() : MyBase::InnerIterator() {} /// This line is problematic: all positions point to InnerIterator and nothing points to MyBase
};

Patch by Serge Preis!

Differential Revision: https://reviews.llvm.org/D32439

llvm-svn: 306103
2017-06-23 14:10:07 +00:00
Serge Pavlov 25dbe1a16e Function with unparsed body is a definition
While a function body is being parsed, the function declaration is not considered
as a definition because it does not have a body yet. In some cases it leads to
incorrect interpretation, the case is presented in
https://bugs.llvm.org/show_bug.cgi?id=14785:
```
    template<typename T> struct Somewhat {
      void internal() const {}
      friend void operator+(int const &, Somewhat<T> const &) {}
    };
void operator+(int const &, Somewhat<char> const &x) { x.internal(); }
```
When statement `x.internal()` in the body of global `operator+` is parsed, the type
of `x` must be completed, so the instantiation of `Somewhat<char>` is started. It
instantiates the declaration of `operator+` defined inline, and makes a check for
redefinition. The check does not detect another definition because the declaration
of `operator+` is still not defining as does not have a body yet.

To solves this problem the function `isThisDeclarationADefinition` considers
a function declaration as a definition if it has flag `WillHaveBody` set.

This change fixes PR14785.

Differential Revision: https://reviews.llvm.org/D30375

This is a recommit of 305379, reverted in 305381, with small changes.

llvm-svn: 305903
2017-06-21 12:46:57 +00:00
Serge Pavlov a4ab1b1c59 Reverted 305379 (Function with unparsed body is a definition)
It broke clang-x86_64-linux-selfhost-modules-2 and some other buildbots.

llvm-svn: 305381
2017-06-14 10:57:56 +00:00
Serge Pavlov c73c81be5c Function with unparsed body is a definition
While a function body is being parsed, the function declaration is not considered
as a definition because it does not have a body yet. In some cases it leads to
incorrect interpretation, the case is presented in
https://bugs.llvm.org/show_bug.cgi?id=14785:
```
    template<typename T> struct Somewhat {
      void internal() const {}
      friend void operator+(int const &, Somewhat<T> const &) {}
    };
void operator+(int const &, Somewhat<char> const &x) { x.internal(); }
```
When statement `x.internal()` in the body of global `operator+` is parsed, the type
of `x` must be completed, so the instantiation of `Somewhat<char>` is started. It
instantiates the declaration of `operator+` defined inline, and makes a check for
redefinition. The check does not detect another definition because the declaration
of `operator+` is still not defining as does not have a body yet.

To solves this problem the function `isThisDeclarationADefinition` considers
a function declaration as a definition if it has flag `WillHaveBody` set.

This change fixes PR14785.

Differential Revision: https://reviews.llvm.org/D30375

llvm-svn: 305379
2017-06-14 10:07:02 +00:00
Serge Pavlov 79271ab154 Do not inherit default arguments for friend function in class template.
A function declared in a friend declaration may have declarations prior
to the containing class definition. If such declaration defines default
argument, the friend function declaration inherits them. This behavior
causes problems if the class where the friend is declared is a template:
during the class instantiation the friend function looks like if it had
default arguments, so error is triggered.

With this change friend functions declared in class templates do not
inherit default arguments. Actual set of them will be defined at the
point where the containing class is instantiated.

This change fixes PR12724.

Differential Revision: https://reviews.llvm.org/D30393

llvm-svn: 304965
2017-06-08 06:31:19 +00:00
Serge Pavlov 673f44c769 Improve diagnostics if friend function redefines file-level function.
Clang makes check for function redefinition after it merged the new
declaration with the existing one. As a result, it produces poor
diagnostics in the case of a friend function defined inline, as in
the code:
```
    void func() {}
    class C { friend void func() {} };
```
Error message in this case states that `inline declaration of 'func'
follows non-inline definition`, which is misleading, as `func` does
not have explicit `inline` specifier.

With this changes compiler reports function redefinition if the new
function is a friend defined inline and it does not have explicit
`inline` specifier.

Differential Revision: https://reviews.llvm.org/D26065

llvm-svn: 304964
2017-06-08 06:07:07 +00:00
Richard Smith b301806c4b PR33318: Add missing full-expression checking to static_assert expression.
This fixes missing lambda-captures for variables referenced only inside a
static_assert (!), among other things.

llvm-svn: 304760
2017-06-06 01:34:24 +00:00