Commit Graph

4186 Commits

Author SHA1 Message Date
Richard Smith 0511d23aeb PR22924, PR22845, some of CWG1464: When checking the initializer for an array
new expression, distinguish between the case of a constant and non-constant
initializer. In the former case, if the bound is erroneous (too many
initializer elements, bound is negative, or allocated size overflows), reject,
and take the bound into account when determining whether we need to
default-construct any elements. In the remanining cases, move the logic to
check for default-constructibility of trailing elements into the initialization
code rather than inventing a bogus array bound, to cope with cases where the
number of initialized elements is not the same as the number of initializer
list elements (this can happen due to string literal initialization or brace
elision).

This also fixes rejects-valid and crash-on-valid errors when initializing a
new'd array of character type from a braced string literal.

llvm-svn: 283406
2016-10-05 22:41:02 +00:00
Reid Kleckner 56f4535634 Test what happens when tag lookup and redeclaration lookup disagree
Clang has a diagnostic for the what happens when an elaborated type
implicitly creates a tag declaration and the initial tag lookup fails,
but the redeclaration lookup succeeds and finds a non-tag type. However,
it wasn't tested, and looked like dead code. After much staring, we
discovered how to exercise it, and are now committing the test for
posterity.

In this example, the tag lookup will not find A, but then when we go to
insert a declaration of A at global scope, we discover the template
friend, which is not a tag type.

  struct C {
    template <typename> friend struct A;
  };
  struct B {
    struct A *p;
  };

llvm-svn: 283235
2016-10-04 18:10:23 +00:00
Reid Kleckner d2c0c25be4 [MS] Move hex long long sign compat hack to -fms-compatibility
Treating large 0x*LL literals as signed instead of unsigned is not a
conforming language extension, so move it out of -fms-extensions.

Came up in PR30605

llvm-svn: 283227
2016-10-04 15:57:49 +00:00
Serge Pavlov 06b7a87298 Do not find friend function definitions inside non-instantiated class.
Previously if a file-level function was defined inside befriending
template class, it always was treated as defined. For instance, the code like:
```
  int func(int x);
  template<typename T> class C1 {
    friend int func(int x) { return x; }
  };
  template<typename T> class C2 {
    friend int func(int x) { return x; }
  };
```
could not be compiled due to function redefinition, although not of the templates
is instantiated. Moreover, the body of friend function can contain use of template
parameters, attempt to get definition of such function outside any instantiation
causes compiler abnormal termination.

Other compilers (gcc, icc) follow viewpoint that the body of the function defined
in friend declaration becomes available when corresponding class is instantiated.
This patch implements this viewpoint in clang.

Definitions introduced by friend declarations in template classes are not added
to the redeclaration chain of corresponding function. Only when the template is
instantiated, instantiation of the function definition is placed to the chain.

The fix was made in collaboration with Richard Smith.

This change fixes PR8035, PR17923, PR22307 and PR25848.

Differential Revision: http://reviews.llvm.org/D16989

llvm-svn: 283207
2016-10-04 10:11:43 +00:00
Gor Nishanov 3e048bb140 [coroutines] Switch to using std::experimental namespace per P0057R5
Summary:
Look for coroutine_traits and friends in std::experimental namespace.
Patch (mostly) by EricWF.

Reviewers: cfe-commits, EricWF, rsmith

Subscribers: majnemer, mehdi_amini

Differential Revision: https://reviews.llvm.org/D25068

llvm-svn: 283170
2016-10-04 00:31:16 +00:00
Alex Lorenz ea9b59a33d Fix PR 28885: Fix AST Printer output for the inherited constructor using
declarations.

This commit ensures that the correct record type is printed out for the
using declarations that represent C++ inherited constructors.
It fixes a regression introduced in r274049 which changed the name that's
stored in the using declarations that correspond to inherited constructors.

Differential Revision: https://reviews.llvm.org/D25131

llvm-svn: 283105
2016-10-03 12:22:17 +00:00
Alex Lorenz 4ff920bf1b Revert r283102 (Typo in the phabricator link)
llvm-svn: 283104
2016-10-03 12:17:56 +00:00
Alex Lorenz 2bc02892be Fix PR 28885: Fix AST Printer output for the inherited constructor using
declarations.

This commit ensures that the correct record type is printed out for the
using declarations that represent C++ inherited constructors.
It fixes a regression introduced in r274049 which changed the name that's
stored in the using declarations that correspond to inherited constructors.

Differential Revision: https://reviews.llvm.org/D25131

llvm-svn: 283102
2016-10-03 12:12:03 +00:00
Gor Nishanov 4ffb434ca8 [coroutines] Rename driver flag -fcoroutines to -fcoroutines-ts
Summary:
Also makes -fcoroutines_ts to be both a Driver and CC1 flag.

Patch mostly by EricWF.

Reviewers: rnk, cfe-commits, rsmith, EricWF

Subscribers: mehdi_amini

Differential Revision: https://reviews.llvm.org/D25130

llvm-svn: 283064
2016-10-02 03:31:58 +00:00
Richard Trieu c2265be186 Fix crash when emitting error.
With templated classes, is possible to not be able to determine is a member
function is a special member function before the class is instantiated.  Only
these special member functions can be defaulted.  In some cases, knowing
whether a function is a special member function can't be determined until
instantiation, so an uninstantiated function could possibly be defaulted too.
Add a case to the error diagnostic when the function marked with a default is
not known to be a special member function.

llvm-svn: 282989
2016-10-01 00:15:24 +00:00
Eric Fiselier 7d5773e610 [coroutines] Diagnose when 'main' is declared as a coroutine.
Summary: The title says it all.

Reviewers: rsmith, GorNishanov

Subscribers: mehdi_amini, cfe-commits

Differential Revision: https://reviews.llvm.org/D25078

llvm-svn: 282973
2016-09-30 22:38:31 +00:00
Eric Fiselier a546528d7b [Coroutines] Fix assertion about uncorrected typos in co_await/co_yield/co_return expressions
llvm-svn: 282792
2016-09-29 21:47:39 +00:00
Richard Trieu 3d1235a97d Revert r282547 and add test to show correct behavior.
llvm-svn: 282555
2016-09-27 23:44:07 +00:00
Richard Trieu 0013782030 Fix defaulted member functions for templated classes.
In some cases, non-special member functions were being marked as being defaulted
in templated classes.  This can cause interactions with later code that expects
the default function to be one of the specific member functions.  Fix the check
so that templated class members are checked the same way as non-templated class
members are.

llvm-svn: 282547
2016-09-27 22:28:59 +00:00
Richard Smith 3b66056a3f [Modules TS] Diagnose 'export' declaration within 'export' declaration.
llvm-svn: 282443
2016-09-26 21:27:23 +00:00
Neil Hickey 50d1ded535 Testing commit rights. Removing trailing white space from test file.
llvm-svn: 281711
2016-09-16 09:38:11 +00:00
Nico Weber d58c26090d Follow-up to r281367: Compare uuids case-insensitively.
llvm-svn: 281430
2016-09-14 01:16:54 +00:00
Nico Weber 88f5ed9430 [clang-cl] Diagnose duplicate uuids.
This mostly behaves cl.exe's behavior, even though clang-cl is stricter in some
corner cases and more lenient in others (see the included test).

To make the uuid declared previously here diagnostic work correctly, tweak
stripTypeAttributesOffDeclSpec() to keep attributes in the right order.

https://reviews.llvm.org/D24469

llvm-svn: 281367
2016-09-13 18:55:26 +00:00
Nico Weber b5bdf3410e Add missing test coverage for an inheritance model attrib merge diag.
Without this, no tests fail if I remove the Diag() in the first if in
Sema::mergeMSInheritanceAttr().

llvm-svn: 281136
2016-09-10 13:03:59 +00:00
Richard Smith 8df390f9eb C++ Modules TS: Add parsing and some semantic analysis support for
export-declarations. These don't yet have an effect on name visibility;
we still export everything by default.

llvm-svn: 280999
2016-09-08 23:14:54 +00:00
George Burgess IV fbad5b2f1b [Sema] Compare bad conversions in overload resolution.
r280553 introduced an issue where we'd emit ambiguity errors for code
like:

```
void foo(int *, int);
void foo(unsigned int *, unsigned int);

void callFoo() {
  unsigned int i;
  foo(&i, 0); // ambiguous: int->unsigned int is worse than int->int,
              // but unsigned int*->unsigned int* is better than
              // int*->int*.
}
```

This patch fixes this issue by changing how we handle ill-formed (but
valid) implicit conversions. Candidates with said conversions now always
rank worse than candidates without them, and two candidates are
considered to be equally bad if they both have these conversions for
the same argument.

Additionally, this fixes a case in C++11 where we'd complain about an
ambiguity in a case like:

```
void f(char *, int);
void f(const char *, unsigned);
void g() { f("abc", 0); }
```

...Since conversion to char* from a string literal is considered
ill-formed in C++11 (and deprecated in C++03), but we accept it as an
extension.

llvm-svn: 280847
2016-09-07 20:03:19 +00:00
Richard Smith 7c2bcc9eb0 Fix clang's handling of the copy performed in the second phase of class
copy-initialization. We previously got this wrong in a couple of ways:
 - we only looked for copy / move constructors and constructor templates for
   this copy, and thus would fail to copy in cases where doing so should use
   some other constructor (but see core issue 670),
 - we mishandled the special case for disabling user-defined conversions that
   blocks infinite recursion through repeated application of a copy constructor
   (applying it in slightly too many cases) -- though as far as I can tell,
   this does not ever actually affect the result of overload resolution, and
 - we misapplied the special-case rules for constructors taking a parameter
   whose type is a (reference to) the same class type by incorrectly assuming
   that only happens for copy/move constructors (it also happens for
   constructors instantiated from templates and those inherited from base
   classes).

These changes should only affect strange corner cases (for instance, where the
copy constructor exists but has a non-const-qualified parameter type), so for
the most part it only causes us to produce more 'candidate' notes, but see the
test changes for other cases whose behavior is affected.

llvm-svn: 280776
2016-09-07 02:14:33 +00:00
Eric Fiselier 341e825eae Implement __attribute__((require_constant_initialization)) for safe static initialization.
Summary:
This attribute specifies expectations about the initialization of static and
thread local variables. Specifically that the variable has a
[constant initializer](http://en.cppreference.com/w/cpp/language/constant_initialization)
according to the rules of [basic.start.static]. Failure to meet this expectation
will result in an error.

Static objects with constant initializers avoid hard-to-find bugs caused by
the indeterminate order of dynamic initialization. They can also be safely
used by other static constructors across translation units.

This attribute acts as a compile time assertion that the requirements
for constant initialization have been met. Since these requirements change
between dialects and have subtle pitfalls it's important to fail fast instead
of silently falling back on dynamic initialization.

```c++
  // -std=c++14
  #define SAFE_STATIC __attribute__((require_constant_initialization)) static
  struct T {
    constexpr T(int) {}
    ~T();
  };
  SAFE_STATIC T x = {42}; // OK.
  SAFE_STATIC T y = 42; // error: variable does not have a constant initializer
  // copy initialization is not a constant expression on a non-literal type.
```
This attribute can only be applied to objects with static or thread-local storage
duration.

Reviewers: majnemer, rsmith, aaron.ballman

Subscribers: jroelofs, cfe-commits

Differential Revision: https://reviews.llvm.org/D23385

llvm-svn: 280525
2016-09-02 18:53:31 +00:00
Eric Fiselier bcdcbd11ba Revert r280516 since it contained accidental changes.
llvm-svn: 280521
2016-09-02 18:43:25 +00:00
Eric Fiselier 92f8935e63 Implement __attribute__((require_constant_initialization)) for safe static initialization.
Summary:
This attribute specifies expectations about the initialization of static and
thread local variables. Specifically that the variable has a
[constant initializer](http://en.cppreference.com/w/cpp/language/constant_initialization)
according to the rules of [basic.start.static]. Failure to meet this expectation
will result in an error.

Static objects with constant initializers avoid hard-to-find bugs caused by
the indeterminate order of dynamic initialization. They can also be safely
used by other static constructors across translation units.

This attribute acts as a compile time assertion that the requirements
for constant initialization have been met. Since these requirements change
between dialects and have subtle pitfalls it's important to fail fast instead
of silently falling back on dynamic initialization.

```c++
  // -std=c++14
  #define SAFE_STATIC __attribute__((require_constant_initialization)) static
  struct T {
    constexpr T(int) {}
    ~T();
  };
  SAFE_STATIC T x = {42}; // OK.
  SAFE_STATIC T y = 42; // error: variable does not have a constant initializer
  // copy initialization is not a constant expression on a non-literal type.
```
This attribute can only be applied to objects with static or thread-local storage
duration.

Reviewers: majnemer, rsmith, aaron.ballman

Subscribers: jroelofs, cfe-commits

Differential Revision: https://reviews.llvm.org/D23385

llvm-svn: 280516
2016-09-02 18:25:29 +00:00
Richard Smith e4caa48dbb DR259: Demote the pedantic error for an explicit instantiation after an
explicit specialization to a warning for C++98 mode (this is a defect report
resolution, so per our informal policy it should apply in C++98), and turn
the warning on by default for C++11 and later. In all cases where it fires, the
right thing to do is to remove the pointless explicit instantiation.

llvm-svn: 280308
2016-08-31 23:23:25 +00:00
Nico Weber 8be5d034e4 fix typo "varaible"
llvm-svn: 279639
2016-08-24 16:37:21 +00:00
Vassil Vassilev 8643639ab4 PR28423: Compare primary declaration contexts.
In certain cases (mostly coming from modules), Sema's idea of the StdNamespace
does not point to the first declaration of namespace std.

Patch by Cristina Cristescu!

Reviewed by Richard Smith.

llvm-svn: 279371
2016-08-20 14:50:22 +00:00
Roger Ferrer Ibanez f7b9f3149b Add missing tests
Change r278483 was missing the tests

Differential Revision: https://reviews.llvm.org/D20561

llvm-svn: 278908
2016-08-17 06:52:15 +00:00
Richard Smith 1879f1069b Disable lambda-capture of decomposition declaration bindings for now, until CWG
agrees on how they're supposed to work.

llvm-svn: 278648
2016-08-15 02:34:23 +00:00
Richard Smith da38363784 P0217R3: code generation support for decomposition declarations.
llvm-svn: 278642
2016-08-15 01:33:41 +00:00
George Burgess IV 53b938da5a [Sema] Fix a crash on variadic enable_if functions.
Currently, when trying to evaluate an enable_if condition, we try to
evaluate all arguments a user passes to a function. Given that we can't
use variadic arguments from said condition anyway, not converting them
is a reasonable thing to do. So, this patch makes us ignore any varargs
when attempting to check an enable_if condition.

We'd crash because, in order to convert an argument, we need its
ParmVarDecl. Variadic arguments don't have ParmVarDecls.

llvm-svn: 278471
2016-08-12 04:12:31 +00:00
Richard Smith 7b76d81bdf P0217R3: serialization/deserialization support for c++17 decomposition declarations.
llvm-svn: 278460
2016-08-12 02:21:25 +00:00
Richard Smith 3997b1b427 P0217R3: template instantiation support for decomposition declarations.
llvm-svn: 278458
2016-08-12 01:55:21 +00:00
Richard Smith dca60b4958 P0217R3: Constant expression evaluation for decomposition declarations.
llvm-svn: 278447
2016-08-12 00:39:32 +00:00
Richard Smith 7873de0cf6 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.

llvm-svn: 278435
2016-08-11 22:25:46 +00:00
Bruno Cardoso Lopes 7ea9fd233b Reapply [Sema] Add sizeof diagnostics for bzero
Reapply r277787. For memset (and others) we can get diagnostics like:

  struct stat { int x; };
  void foo(struct stat *stamps) {
    bzero(stamps, sizeof(stamps));
    memset(stamps, 0, sizeof(stamps));
  }

  t.c:7:28: warning: 'memset' call operates on objects of type 'struct stat' while the size is based on a different type 'struct stat *' [-Wsizeof-pointer-memaccess]
    memset(stamps, 0, sizeof(stamps));
           ~~~~~~            ^~~~~~
  t.c:7:28: note: did you mean to dereference the argument to 'sizeof' (and multiply it by the number of elements)?
    memset(stamps, 0, sizeof(stamps));
                             ^~~~~~

This patch implements the same class of warnings for bzero.

Differential Revision: https://reviews.llvm.org/D22525

rdar://problem/18963514

llvm-svn: 278264
2016-08-10 18:34:47 +00:00
Richard Trieu e056aee9d9 Fix typos from r277797 and unused variable from r277889.
llvm-svn: 277900
2016-08-06 01:44:06 +00:00
Richard Trieu 81b6c561ea Fix two false positives in -Wreturn-stack-address
If the return type is a pointer and the function returns the reference to a
pointer, don't warn since only the value is returned, not the reference.

If a reference function parameter appears in the reference chain, don't warn
since binding happens at the caller scope, so addresses returned are not
to local stack.  This includes default arguments as well.

llvm-svn: 277889
2016-08-05 23:24:47 +00:00
Richard Trieu 71d74d4b25 Fix false positive in -Wunsequenced and templates.
For builtin logical operators, there is a well-defined ordering of argument
evaluation.  For overloaded operator of the same type, there is no argument
evaluation order, similar to other function calls.  When both are present,
uninstantiated templates with an operator&& is treated as an unresolved
function call.  Unresolved function calls are treated as normal function calls,
and may result in false positives when the builtin logical operator is used.
Have the unsequenced checker ignore dependent expressions to avoid this
false positive.  The check also happens in template instantiations to catch
when the overloaded operator is used.

llvm-svn: 277866
2016-08-05 21:02:34 +00:00
Bruno Cardoso Lopes 9e4374daa3 Revert "[Sema] Add sizeof diagnostics for bzero"
This reverts commit r277787, which caused PR28870.

llvm-svn: 277830
2016-08-05 16:41:00 +00:00
Bruno Cardoso Lopes edf3d81cbf [Sema] Add sizeof diagnostics for bzero
For memset (and others) we can get diagnostics like:

  struct stat { int x; };
  void foo(struct stat *stamps) {
    bzero(stamps, sizeof(stamps));
    memset(stamps, 0, sizeof(stamps));
  }

  t.c:7:28: warning: 'memset' call operates on objects of type 'struct stat' while the size is based on a different type 'struct stat *' [-Wsizeof-pointer-memaccess]
    memset(stamps, 0, sizeof(stamps));
           ~~~~~~            ^~~~~~
  t.c:7:28: note: did you mean to dereference the argument to 'sizeof' (and multiply it by the number of elements)?
    memset(stamps, 0, sizeof(stamps));
                             ^~~~~~

This patch implements the same class of warnings for bzero.

Differential Revision: https://reviews.llvm.org/D22525

rdar://problem/18963514

llvm-svn: 277787
2016-08-04 23:55:22 +00:00
Devin Coughlin 6eb1ca7416 [CFG] Fix crash finding destructor of lifetime-extended temporary.
Fix a crash under -Wthread-safety when finding the destructor for a
lifetime-extending reference.

A patch by Nandor Licker!

Differential Revision: https://reviews.llvm.org/D22419

llvm-svn: 277522
2016-08-02 21:07:23 +00:00
Faisal Vali 5e5501861a [NFC] Rearrange an example-file so the c++14 specific example is on top.
This makes it easier to add C++1z examples to the bottom, just before the #endif.

llvm-svn: 277287
2016-07-31 01:19:17 +00:00
Erik Pilkington 3cdc317342 [Sema] Teach getCurrentThisType to reconize lambda in in-class initializer
Fixes PR27994, a crash on valid.

Differential revision: https://reviews.llvm.org/D21145

llvm-svn: 276900
2016-07-27 18:25:10 +00:00
Faisal Vali c6b9be29f2 [cxx1z-constexpr-lambda] Make a lambda's closure type eligible as a literal-type in C++1z
Additionally, for pre-C++1z, instead of forbidding a lambda's closure type from being a literal type through circumlocutorily setting HasNonLiteralTypeFieldsOrBases falsely to true -- handle lambda's more directly in CXXRecordDecl::isLiteral().

One additional small step towards implementing constexpr-lambdas.

Thanks to Richard Smith for his review! 
https://reviews.llvm.org/D22662

llvm-svn: 276514
2016-07-23 04:05:19 +00:00
Richard Smith bdb84f374c 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).

llvm-svn: 276492
2016-07-22 23:36:59 +00:00
George Burgess IV 92b43a462e [Sema] Fix PR28623.
In atomic builtins, we assumed that the LValue conversion on the first
argument would succeed. So, we would crash given code like:

```
void ovl(char);
void ovl(int);
__atomic_store_n(ovl, 0, 0);
```

This patch makes us not assume that said conversion is successful. :)

llvm-svn: 276232
2016-07-21 03:28:13 +00:00
Akira Hatanaka 73118fd10e [Sema] Compute the nullability of a conditional expression based on the
nullabilities of its operands.

This patch defines a function to compute the nullability of conditional
expressions, which enables Sema to precisely detect implicit conversions
of nullable conditional expressions to nonnull pointers.

rdar://problem/25166556

Differential Revision: https://reviews.llvm.org/D22392

llvm-svn: 276076
2016-07-20 01:48:11 +00:00
Dmitry Polukhin ba57f02720 Deprecated (legacy) string literal conversion to 'char *' causes strange overloading resolution
It's a patch for PR28050. Seems like overloading resolution wipes out
the first standard conversion sequence (before user-defined conversion)
in case of deprecated string literal conversion.

Differential revision: https://reviews.llvm.org/D21228

Patch by Alexander Makarov

llvm-svn: 275970
2016-07-19 11:29:16 +00:00
Richard Smith 3cbf3f1f59 Push alias-declarations and alias-template declarations into scope even if
they're redeclarations. This is necessary in order for name lookup to correctly
find the most recent declaration of the name (which affects default template
argument lookup and cross-module merging, among other things).

llvm-svn: 275612
2016-07-15 20:53:25 +00:00
Saleem Abdulrasool 511f2e5a89 Sema: support __declspec(dll*) on ObjC interfaces
Extend the __declspec(dll*) attribute to cover ObjC interfaces.  This was
requested by Microsoft for their ObjC support.  Cover both import and export.
This only adds the semantic analysis portion of the support, code-generation
still remains outstanding.  Add some basic initial documentation on the
attributes that were previously empty.  Tweak the previous tests to use the
relative expected-warnings to make the tests easier to read.

llvm-svn: 275610
2016-07-15 20:41:10 +00:00
Paul Robinson 4e0ff9c46b C does not have inline variables.
Add a few missing tests for related C++ diagnostics.

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

llvm-svn: 275493
2016-07-14 22:22:58 +00:00
Roger Ferrer Ibanez 58b8e483f0 Reverting 275417
This change has triggered unexpected failures.

llvm-svn: 275462
2016-07-14 20:05:30 +00:00
Roger Ferrer Ibanez 585ea9ddce Diagnose taking address and reference binding of packed members
This patch implements PR#22821.

Taking the address of a packed member is dangerous since the reduced
alignment of the pointee is lost. This can lead to memory alignment
faults in some architectures if the pointer value is dereferenced.

This change adds a new warning to clang emitted when taking the address
of a packed member. A packed member is either a field/data member
declared as attribute((packed)) or belonging to a struct/class
declared as such. The associated flag is -Waddress-of-packed-member.
Conversions (either implicit or via a valid casting) to pointer types
with lower or equal alignment requirements (e.g. void* or char*)
silence the warning.

This change also adds a new error diagnostic when the user attempts to
bind a reference to a packed member, regardless of the alignment.

Differential Revision: https://reviews.llvm.org/D20561

llvm-svn: 275417
2016-07-14 14:10:43 +00:00
Richard Smith a547eb27fa P0305R0: Semantic analysis and code generation for C++17 init-statement for 'if' and 'switch':
if (stmt; condition) { ... }

Patch by Anton Bikineev! Some minor formatting and comment tweets by me.

llvm-svn: 275350
2016-07-14 00:11:03 +00:00
David Majnemer c2406d46b8 [Sema] Don't artificially forbid BuiltinTemplateDecls in CheckTemplateArgument
After thinking about it, we don't really need to forbid
BuiltinTemplateDecls explicitly.  The restriction doesn't really buy us
anything.

llvm-svn: 275078
2016-07-11 17:09:56 +00:00
David Majnemer f580dd98cb [Sema] Disallow __make_integer_seq from showing up in __make_integer_seq
We hit over stringent asserts when trying to diagnose.  Loosen them as
appropriate.

This fixes PR28494.

llvm-svn: 275047
2016-07-11 05:59:24 +00:00
Vassil Vassilev 1002373946 Teach -ast-print to print constexpr variables.
Patch reviewed by Richard Smith (D22168).

llvm-svn: 274930
2016-07-08 21:09:08 +00:00
Vassil Vassilev cdaa31fe84 Don't crash when printing auto variables.
Patch by Axel Naumann!

llvm-svn: 274859
2016-07-08 16:04:22 +00:00
Manman Ren ebe8cf55ac C++14 init-capture: error out instead of crashing.
When we have template arguments, we have a function and a pattern, the variable
in init-capture belongs to the pattern decl when checking if the lhs of
"max = current" is modifiable:
  auto find = [max = init](auto current) {
    max = current;
  };

In function isReferenceToNonConstCapture, we handle the case where the decl
context for the variable is not part of the current context.

Instead of crashing, we emit an error message:
cannot assign to a variable captured by copy in a non-mutable lambda

rdar://26997922

llvm-svn: 274392
2016-07-01 22:27:16 +00:00
Eric Fiselier 6ad68551c3 [Feature] Add a builtin for indexing into parameter packs. Patch by Louis Dionne.
This patch adds a __nth_element builtin that allows fetching the n-th type of a
parameter pack with very little compile-time overhead. The patch was inspired by
r252036 and r252115 by David Majnemer, which add a similar __make_integer_seq
builtin for efficiently creating a std::integer_sequence.

Reviewed as D15421. http://reviews.llvm.org/D15421

llvm-svn: 274316
2016-07-01 01:24:09 +00:00
Erik Pilkington fc235eb780 [Sema] Implement C++14's DR1579: Prefer returning by converting move constructor
Fixes PR28096.

Differential Revision: http://reviews.llvm.org/D21619

llvm-svn: 274291
2016-06-30 23:09:13 +00:00
Richard Smith b8c414ccd1 Fix typo-correction crash if a typo occurs within the operand of a
function-style cast to a non-dependent type which is then used in an invalid
way. We'd lose the "type dependent" bit here, and downstream Sema processing
would then discard the expression if it was used in a context where its type
rendered it invalid.

llvm-svn: 274267
2016-06-30 20:24:30 +00:00
Richard Smith cc4bb63351 PR28373: fix crash-on-invalid if the condition of an if-statement fails typo-correction.
llvm-svn: 274260
2016-06-30 18:36:34 +00:00
Dmitry Polukhin 90bb49e362 [GCC] PR23529 Mangler part of attrbute abi_tag support
Original patch by Stefan Bühler http://reviews.llvm.org/D12834

Difference between original and this one:
- fixed all failing tests
- fixed mangling for global variable outside namespace
- emit ABI tags for guards and local names
- clang-format + other stylistic changes
- significantly reworked patch according to Richard's suggestions

Sema part, committed before http://reviews.llvm.org/D17567

Differential revision: http://reviews.llvm.org/D18035

llvm-svn: 274222
2016-06-30 09:40:38 +00:00
Richard Smith 80a4702d02 Mark inheriting constructors as deleted if the corresponding defaulted default
constructor would be; this is effectively required by P0136R1. This has the
effect of exposing the validity of the base class initialization steps to
SFINAE checks.

llvm-svn: 274088
2016-06-29 01:10:27 +00:00
Richard Smith 3ffc45f5fd Function declarations are, in fact, permitted in the init-statement of a for
loop. Don't confuse Sema by saying they're not.

llvm-svn: 274080
2016-06-28 23:26:18 +00:00
Manman Ren ccf25bbf3f AvailabilityAttr: we accept "macos" as the platform name.
We continue accepting "macosx" but canonicalize it to "macos", When emitting
diagnostics, we use "macOS" instead of "OS X".

The PlatformName in TargetInfo is changed from "macosx" to "macos" so we can
directly compare the Platform in AvailabilityAttr with the PlatformName
in TargetInfo.

rdar://26795172
rdar://26800775

llvm-svn: 274064
2016-06-28 20:55:30 +00:00
Richard Smith 5179eb7821 P0136R1, DR1573, DR1645, DR1715, DR1736, DR1903, DR1941, DR1959, DR1991:
Replace inheriting constructors implementation with new approach, voted into
C++ last year as a DR against C++11.

Instead of synthesizing a set of derived class constructors for each inherited
base class constructor, we make the constructors of the base class visible to
constructor lookup in the derived class, using the normal rules for
using-declarations.

For constructors, UsingShadowDecl now has a ConstructorUsingShadowDecl derived
class that tracks the requisite additional information. We create shadow
constructors (not found by name lookup) in the derived class to model the
actual initialization, and have a new expression node,
CXXInheritedCtorInitExpr, to model the initialization of a base class from such
a constructor. (This initialization is special because it performs real perfect
forwarding of arguments.)

In cases where argument forwarding is not possible (for inalloca calls,
variadic calls, and calls with callee parameter cleanup), the shadow inheriting
constructor is not emitted and instead we directly emit the initialization code
into the caller of the inherited constructor.

Note that this new model is not perfectly compatible with the old model in some
corner cases. In particular:
 * if B inherits a private constructor from A, and C uses that constructor to
   construct a B, then we previously required that A befriends B and B
   befriends C, but the new rules require A to befriend C directly, and
 * if a derived class has its own constructors (and so its implicit default
   constructor is suppressed), it may still inherit a default constructor from
   a base class

llvm-svn: 274049
2016-06-28 19:03:57 +00:00
Richard Smith 03a4aa3d00 Re-commit r273548, reverted in r273589, with a fix to not produce
-Wfor-loop-analysis warnings for a for-loop with a condition variable. In such
a case, the loop condition variable is modified on each iteration of the loop
by definition.

Original commit message:

Rearrange condition handling so that semantic checks on a condition variable
are performed before the other substatements of the construct are parsed,
rather than deferring them until the end. This allows better error recovery
from semantic errors in the condition, improves diagnostic order, and is a
prerequisite for C++17 constexpr if.

llvm-svn: 273600
2016-06-23 19:02:52 +00:00
Peter Collingbourne ae72fa2f97 Add a test case for the regression in -Wfor-loop-analysis caused by r273548.
llvm-svn: 273590
2016-06-23 18:11:19 +00:00
Peter Collingbourne b77ebd749a Revert r273548, "Rearrange condition handling so that semantic checks on a condition variable"
as it caused a regression in -Wfor-loop-analysis.

llvm-svn: 273589
2016-06-23 18:11:15 +00:00
Richard Smith 19f877c3f2 Rearrange condition handling so that semantic checks on a condition variable
are performed before the other substatements of the construct are parsed,
rather than deferring them until the end. This allows better error recovery
from semantic errors in the condition, improves diagnostic order, and is a
prerequisite for C++17 constexpr if.

llvm-svn: 273548
2016-06-23 08:41:20 +00:00
Erik Pilkington 71a7d912dc [Sema] Only define function as move assignment when needed
Fixes PR27941, a crash on invalid.

Differential revision: http://reviews.llvm.org/D20923

llvm-svn: 273193
2016-06-20 20:04:15 +00:00
Olivier Goffart 12b2219841 Functions declared in a scope should not hide previous declaration in earlier scopes
This code should be an error:

 void foo(int);
 void f3() {
   int foo(float);
   {
     float foo(int); // expected-error {{functions that differ only in their return type cannot be overloaded}}
   }
 }

the foo(float) function declared at function scope should not hide the float(int)
while trying to redeclare functions.

Differential Revision: http://reviews.llvm.org/D19763

llvm-svn: 272961
2016-06-16 21:39:46 +00:00
Roger Ferrer Ibanez 985c0c274b Reverting "Warn when taking address of a packed member"
This new diagnostic is causing some false positives that have to be addressed.

This reverts commit 272552

llvm-svn: 272653
2016-06-14 11:20:07 +00:00
Faisal Vali 81a88beec4 Fix PR28100 - Allow redeclarations of deleted explicit specializations.
See https://llvm.org/bugs/show_bug.cgi?id=28100.

In r266561 when I implemented allowing explicit specializations of function templates to override deleted status, I mistakenly assumed (and hence introduced a violable assertion) that when an explicit specialization was being declared, the corresponding specialization of the most specialized function template that it would get linked to would always be the one that was implicitly generated - and so if it was marked as 'deleted' it must have inherited it from the primary template and so should be safe to reset its deleted status, and set it to being an explicit specialization.  Obviously during redeclaration of a deleted explicit specialization, in order to avoid a recursive reset, we need to check that the previous specialization is not an explicit specialization (instead of assuming and asserting it) and that it hasn't been referenced, and so only then is it safe to reset its 'deleted' status.

All regression tests pass.

Thanks to Zhendong Su for reporting the bug and David Majnemer for tracking it to my commit r266561, and promptly bringing it to my attention.

llvm-svn: 272631
2016-06-14 03:23:15 +00:00
Serge Pavlov b82a9401df Detect recursive default argument definition
If definition of default function argument uses itself, clang crashed,
because corresponding function parameter is not associated with the default
argument yet. With this fix clang emits appropriate error message.

This change fixes PR28105.

Differential Revision: http://reviews.llvm.org/D21301

llvm-svn: 272623
2016-06-14 02:55:56 +00:00
Roger Ferrer Ibanez ac6617b288 Warn when taking address of a packed member
This patch implements PR#22821.

Taking the address of a packed member is dangerous since the reduced
alignment of the pointee is lost. This can lead to memory alignment
faults in some architectures if the pointer value is dereferenced.

This change adds a new warning to clang emitted when taking the address
of a packed member. A packed member is either a field/data member
declared as attribute((packed)) or belonging to a struct/class
declared as such. The associated flag is -Waddress-of-packed-member

Differential Revision: http://reviews.llvm.org/D20561

llvm-svn: 272552
2016-06-13 15:41:40 +00:00
Faisal Vali 67b04465c0 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.

llvm-svn: 272480
2016-06-11 16:41:54 +00:00
David Majnemer 5d321e63c0 [Sema] Return an appropriate result from CheckSpecifiedExceptionType
We shouldn't return true from CheckSpecifiedExceptionType if
the record type is incomplete and -fms-extensions is engaged.  Otherwise
we will have an incomplete AST.

llvm-svn: 272447
2016-06-11 01:25:04 +00:00
David Majnemer b2b0da4ad0 [-fms-extensions] Permit incomplete types in dynamic exception specifications
Microsoft headers, comdef.h and comutil.h, assume that this is an OK
thing to do.  Downgrade the hard error to a warning if we are in
-fms-extensions mode.

This fixes PR28080.

llvm-svn: 272412
2016-06-10 18:24:41 +00:00
David Majnemer 76a256260e [Sema] Don't crash when a field w/ a mem-initializer clashes with a record name
It is possible for a field and a class to have the same name.  In such
cases, performing lookup for the field might return a result set with
more than one entry.  An overzealous assertion fired, causing us to
crash instead of using the non-class lookup result.

This fixes PR28060.

llvm-svn: 272247
2016-06-09 05:26:56 +00:00
David Majnemer e56d1a0d50 [Sema] Don't permit catching variably modified types
Variably modified types shouldn't be permitted in catch clauses.

This fixes PR28047.

llvm-svn: 272159
2016-06-08 16:05:07 +00:00
George Burgess IV beca4a3338 [Sema] Teach CheckPlaceholderExpr about unaddressable functions.
Given the following C++:

```
void foo();
void foo() __attribute__((enable_if(false, "")));

bool bar() {
  auto P = foo;
  return P == foo;
}
```

We'll currently happily (and correctly) resolve `foo` to the `foo`
overload without `enable_if` when assigning to `P`. However, we'll
complain about an ambiguous overload on the `P == foo` line, because
`Sema::CheckPlaceholderExpr` doesn't recognize that there's only one
`foo` that could possibly work here.

This patch teaches `Sema::CheckPlaceholderExpr` how to properly deal
with such cases.

Grepping for other callers of things like
`Sema::ResolveAndFixSingleFunctionTemplateSpecialization`, it *looks*
like this is the last place that needed to be fixed up. If I'm wrong,
I'll see if there's something we can do that beats what amounts to
whack-a-mole with bugs.

llvm-svn: 272080
2016-06-08 00:34:22 +00:00
Saleem Abdulrasool ada78feb08 Sema: do not attempt to sizeof a dependent type
We would attempt to evaluate the sizeof a dependent type to check for an
integral overflow.  However, because the dependent type is not yet resolved, we
cannot determine if the expression would overflow.  Report a failure to perform
a symbolic evaluation of a constant involving the dependent type.

llvm-svn: 271762
2016-06-04 03:16:21 +00:00
Richard Smith 3a09d8be7c PR27989: only enqueue binary operators into the data recursive int expression
evaluator if they are actually int expressions.

llvm-svn: 271754
2016-06-04 00:22:31 +00:00
Olivier Goffart eeba9e4066 Fix crash while parsing variable template with variadic template arguments
It is only a crash if the compiler optimize for this!=nullptr because
LocalInstantiationScope::getPartiallySubstitutedPack checks if 'this' is null
(This is crashing when clang is compiled with GCC6)

Differential Revision: http://reviews.llvm.org/D20511

llvm-svn: 270845
2016-05-26 12:55:34 +00:00
Andrey Bokhanko 67a4186ee6 [MSVC] Support for __unaligned qualifier in functions
This implements support for MS-specific __unaligned qualifier in functions and
makes the following test case both compile and mangle correctly:

struct S {
    void f() __unaligned;
};
void S::f() __unaligned {
}

Differential Revision: http://reviews.llvm.org/D20437

llvm-svn: 270834
2016-05-26 10:06:01 +00:00
George Burgess IV 8c892b556f [Sema] Note when we encounter a problem in ExprConstant.
Currently, the constexpr evaluator is very conservative about unmodeled
side-effects when we're evaluating an expression in a mode that allows
such side-effects.

This patch makes us note when we might have actually encountered an
unmodeled side-effect, which allows us to be more accurate when we know
an unmodeled side-effect couldn't have occurred.

This patch has been split into two commits; this one primarily
introduces the bits necessary to track whether we might have potentially
hit such a side-effect. The one that actually does the tracking (which
boils down to more or less a rename of keepEvaluatingAfterFailure to
noteFailure) is coming soon.

Differential Revision: http://reviews.llvm.org/D18540

llvm-svn: 270781
2016-05-25 22:31:54 +00:00
Richard Smith c0d04a2567 Fix rejects-valid on constexpr function that accesses a not-yet-defined 'extern
const' variable. That variable might be defined as 'constexpr', so we cannot
prove that a use of it could never be a constant expression.

llvm-svn: 270774
2016-05-25 22:06:25 +00:00
Denis Zobnin eebc4af0ed [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

llvm-svn: 270686
2016-05-25 11:32:42 +00:00
Richard Smith 22e7cc6a32 Properly track the found declaration (possibly a using-declaration) when
handling an explicit member specialization.

llvm-svn: 270514
2016-05-24 00:01:49 +00:00
Richard Smith cc1b82be17 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.

llvm-svn: 270482
2016-05-23 20:03:04 +00:00
David Majnemer 7eca8a3d41 Address post-commit review feedback to r270457
Add two tests which show our error handling behavior for invalid
parameters in the layout_version and empty_bases attributes.

Amend our documentation to make it more clear that
__declspec(empty_bases) and __declspec(layout_version) can only apply to
classes, structs, and unions.

llvm-svn: 270461
2016-05-23 17:32:35 +00:00
David Majnemer b3d96882ec Clang support for __is_assignable intrinsic
MSVC now supports the __is_assignable type trait intrinsic,
to enable easier and more efficient implementation of the
Standard Library's is_assignable trait.
As of Visual Studio 2015 Update 3, the VC Standard Library
implementation uses the new intrinsic unconditionally.

The implementation is pretty straightforward due to the previously
existing is_nothrow_assignable and is_trivially_assignable.
We handle __is_assignable via the same code as the other two except
that we skip the extra checks for nothrow or triviality.

Patch by Dave Bartolomeo!

Differential Revision: http://reviews.llvm.org/D20492

llvm-svn: 270458
2016-05-23 17:21:55 +00:00
David Majnemer cd3ebfe293 [MS ABI] Implement __declspec(empty_bases) and __declspec(layout_version)
The layout_version attribute is pretty straightforward: use the layout
rules from version XYZ of MSVC when used like
struct __declspec(layout_version(XYZ)) S {};

The empty_bases attribute is more interesting.  It tries to get the C++
empty base optimization to fire more often by tweaking the MSVC ABI
rules in subtle ways:
1. Disable the leading and trailing zero-sized object flags if a class
   is marked __declspec(empty_bases) and is empty.

   This means that given:
   struct __declspec(empty_bases) A {};
   struct __declspec(empty_bases) B {};
   struct C : A, B {};

   'C' will have size 1 and nvsize 0 despite not being annotated
   __declspec(empty_bases).

2. When laying out virtual or non-virtual bases, disable the injection
   of padding between classes if the most derived class is marked
   __declspec(empty_bases).

   This means that given:
   struct A {};
   struct B {};
   struct __declspec(empty_bases) C : A, B {};

   'C' will have size 1 and nvsize 0.

3. When calculating the offset of a non-virtual base, choose offset zero
   if the most derived class is marked __declspec(empty_bases) and the
   base is empty _and_ has an nvsize of 0.

   Because of the ABI rules, this does not mean that empty bases
   reliably get placed at offset 0!

   For example:
   struct A {};
   struct B {};
   struct __declspec(empty_bases) C : A, B { virtual ~C(); };

   'C' will be pointer sized to account for the vfptr at offset 0.
   'A' and 'B' will _not_ be at offset 0 despite being empty!
   Instead, they will be located right after the vfptr.

   This occurs due to the interaction betweeen non-virtual base layout
   and virtual function pointer injection: injection occurs after the
   nv-bases and shifts them down by the size of a pointer.

llvm-svn: 270457
2016-05-23 17:16:12 +00:00
Richard Smith 484f13aeb1 Revert accidentally-committed test for PR27558 (which currently fails...)
llvm-svn: 270010
2016-05-19 01:41:52 +00:00
Richard Smith 301bc21fd0 Make Sema::getPrintingPolicy less ridiculously expensive. This used to perform
an identifier table lookup, *and* copy the LangOptions (including various
std::vector<std::string>s). Twice. We call this function once each time we start
parsing a declaration specifier sequence, and once for each call to Sema::Diag.

This reduces the compile time for a sample .c file from the linux kernel by 20%.

llvm-svn: 270009
2016-05-19 01:39:10 +00:00
Vassil Vassilev 2ee10e6dc6 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.

llvm-svn: 269935
2016-05-18 15:14:46 +00:00
Nick Lewycky 2eeddfb1ef Warn when a reference is bound to an empty l-value (dereferenced null pointer).
llvm-svn: 269572
2016-05-14 17:44:14 +00:00
Richard Smith 9385d704c1 When typo-correcting a using-declaration, actually correct the name of the
UsingDecl (so that redeclaration lookup can find it).

llvm-svn: 269530
2016-05-14 01:58:49 +00:00
Richard Smith 12e7931d0b Add support for derived class special members hiding functions brought in from
a base class via a using-declaration. If a class has a using-declaration
declaring either a constructor or an assignment operator, eagerly declare its
special members in case they need to displace a shadow declaration from a
using-declaration.

llvm-svn: 269398
2016-05-13 06:47:56 +00:00
Richard Smith 845d0d74ba Extend this test to also be valid in C++14.
llvm-svn: 269397
2016-05-13 06:42:55 +00:00
Andrey Bokhanko 45d413260e [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

llvm-svn: 269220
2016-05-11 18:38:21 +00:00
George Burgess IV e8f10cc0b9 [Sema] Fix value-dependent enable_if bug.
This patch fixes a bug where we would assume all value-dependent
enable_if conditions give successful results.

Instead, we consider value-dependent enable_if conditions to always
fail. While this isn't ideal, this is the best we can realistically do
without changing both enable_if's semantics and large parts of Sema
(specifically, all of the parts that don't expect type dependence to
come out of nowhere, and that may interact with overload resolution).

Differential Revision: http://reviews.llvm.org/D20130

llvm-svn: 269154
2016-05-11 01:38:27 +00:00
Nemanja Ivanovic bb1ea2d613 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.

llvm-svn: 268898
2016-05-09 08:52:33 +00:00
Olivier Goffart 63a2083be9 Fix spurious warnings about unused private field
If the address of a field is taken as a pointer to member, we should
not warn that the field is not used.

Normaly, yse of fields are done from MemberExpr, but in case of pointer to
member, it is in a DeclRefExpr

Differential Revision: http://reviews.llvm.org/D20054

llvm-svn: 268895
2016-05-09 07:09:51 +00:00
Nico Weber 2801d32c07 Revert r268727, it caused PR27666.
llvm-svn: 268736
2016-05-06 14:34:29 +00:00
Andrey Bokhanko ba0d7540e3 [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

llvm-svn: 268727
2016-05-06 11:47:55 +00:00
Richard Smith 5cbeb75a99 Fix implementation of C++'s restrictions on using-declarations referring to enumerators:
* an unscoped enumerator whose enumeration is a class member is itself a class
   member, so can only be the subject of a class-scope using-declaration.

 * a scoped enumerator cannot be the subject of a class-scope using-declaration.

llvm-svn: 268594
2016-05-05 02:13:49 +00:00
Reid Kleckner 327b06400f Fix crash in BuildCXXDefaultInitExpr.
Fix crash in BuildCXXDefaultInitExpr when member of template class has
same name as the class itself.

Based on patch by Raphael "Teemperor" Isemann!

Differential Revision: http://reviews.llvm.org/D19721

llvm-svn: 268082
2016-04-29 18:06:53 +00:00
Denis Zobnin 2290dacaf8 Recommit "[MS] Improved implementation of stack pragmas (vtordisp, *_seg)"
Slightly updated version, double-checked build and tests.
Improve implementation of MS pragmas that use stack + compatibility fixes.
This patch:
  1. Changes implementation of #pragma vtordisp to use PragmaStack class
     that other stack pragmas use;
  2. Fixes "#pragma vtordisp()" behavior - it shouldn't affect the stack;
  3. Supports "save-restore" of pragma stacks on enter / exit a C++ method
     body, as MSVC does.

TODO:
  1. Change implementation of #pragma pack to use the same approach;
  2. Introduce diagnostics on popping named stack slots, as MSVC does.

Reviewers:
  rnk, thakis

Differential revision: http://reviews.llvm.org/D19361

llvm-svn: 268029
2016-04-29 11:27:00 +00:00
Alexey Bataev e7545b33ff Implementation of VlA of GNU C++ extension, by Vladimir Yakovlev.
This enables GNU C++ extension "Variable length array" by default.
Differential Revision: http://reviews.llvm.org/D18823

llvm-svn: 268018
2016-04-29 09:39:50 +00:00
Akira Hatanaka 10aced824a [Parser] Clear the TemplateParamScope bit of the current scope's flag
if we are parsing a template specialization.

This commit makes changes to clear the TemplateParamScope bit and set
the TemplateParamParent field of the current scope to null if a template
specialization is being parsed.

Before this commit, Sema::ActOnStartOfLambdaDefinition would check
whether the parent template scope had any decls to determine whether
or not a template specialization was being parsed. This wasn't correct
since it couldn't distinguish between a real template specialization and
a template defintion with an unnamed template parameter (only template
parameters with names are added to the scope's decl list). To fix the
bug, this commit changes the code to check the pointer to the parent
template scope rather than the decl list.

rdar://problem/23440346

Differential Revision: http://reviews.llvm.org/D19175

llvm-svn: 267975
2016-04-29 02:24:14 +00:00
Reid Kleckner f463a8a424 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

llvm-svn: 267957
2016-04-29 00:37:43 +00:00
Akira Hatanaka b87faffdb9 [Sema] Fix a crash that occurs when a variable template is initialized
with a generic lambda.

This patch fixes Sema::InstantiateVariableInitializer to switch to the
context of the variable before instantiating its initializer, which is
necessary to set the correct type for VarTemplateSpecializationDecl.

This is the first part of the patch that was reviewed here:
http://reviews.llvm.org/D19175

rdar://problem/23440346

llvm-svn: 267956
2016-04-28 23:50:12 +00:00
Peter Collingbourne 3afb266886 Re-apply r267784, r267824 and r267830.
I have updated the compiler-rt tests.

llvm-svn: 267903
2016-04-28 17:09:37 +00:00
Benjamin Kramer 5556a5cf3b Revert r267784, r267824 and r267830.
It makes compiler-rt tests fail if the gold plugin is enabled.

Revert "Rework interface for bitset-using features to use a notion of LTO visibility."
Revert "Driver: only produce CFI -fvisibility= error when compiling."
Revert "clang/test/CodeGenCXX/cfi-blacklist.cpp: Exclude ms targets. They would be non-cfi."

llvm-svn: 267871
2016-04-28 12:14:47 +00:00
Denis Zobnin 801d9b0cc4 Revert "[MS] Improved implementation of MS stack pragmas (vtordisp, *_seg)"
This reverts commit r267866.

llvm-svn: 267870
2016-04-28 11:32:10 +00:00
Denis Zobnin 2008dbb4ed [MS] Improved implementation of MS stack pragmas (vtordisp, *_seg)
Rework implementation of several MS pragmas that use internal stack:
vtordisp, {bss|code|const|data}_seg.
This patch:
  1. Makes #pragma vtordisp use PragmaStack class as *_seg pragmas do;
  2. Fixes "#pragma vtordisp()" behavior: it shouldn't affect stack;
  3. Saves/restores the stacks on enter/exit a C++ method body.

llvm-svn: 267866
2016-04-28 10:13:18 +00:00
Dmitry Polukhin 5b4faeec87 Revert "[MSVC] PR27337: allow static_cast from private base to derived for WTL"
This reverts commit r267534.

llvm-svn: 267865
2016-04-28 09:56:22 +00:00
Peter Collingbourne a8b2f7c0d7 Rework interface for bitset-using features to use a notion of LTO visibility.
Bitsets, and the compiler features they rely on (vtable opt, CFI),
only have visibility within the LTO'd part of the linkage unit. Therefore,
only enable these features for classes with hidden LTO visibility. This
notion is based on object file visibility or (on Windows)
dllimport/dllexport attributes.

We provide the [[clang::lto_visibility_public]] attribute to override the
compiler's LTO visibility inference in cases where the class is defined
in the non-LTO'd part of the linkage unit, or where the ABI supports
calling classes derived from abstract base classes with hidden visibility
in other linkage units (e.g. COM on Windows).

If the cross-DSO CFI mode is enabled, bitset checks are emitted even for
classes with public LTO visibility, as that mode uses a separate mechanism
to cause bitsets to be exported.

This mechanism replaces the whole-program-vtables blacklist, so remove the
-fwhole-program-vtables-blacklist flag.

Because __declspec(uuid()) now implies [[clang::lto_visibility_public]], the
support for the special attr:uuid blacklist entry is removed.

Differential Revision: http://reviews.llvm.org/D18635

llvm-svn: 267784
2016-04-27 20:39:53 +00:00
Dmitry Polukhin e9b2548f29 [MSVC] PR27337: allow static_cast from private base to derived for WTL
MSVC doesn't report even warning for cast from private base class to
derived.

Differential Revision: http://reviews.llvm.org/D19477

llvm-svn: 267534
2016-04-26 09:21:17 +00:00
Richard Smith 2414bcabd2 Implement support for conditional between xvalues of reference-compatible
types. Patch by Erik Pilkington!

llvm-svn: 267454
2016-04-25 19:30:37 +00:00
Aaron Ballman 1de59c5d92 Improve diagnostic checking for va_start to also warn on other instances of undefined behavior, such as a parameter declared with the register keyword in C, or a parameter of a type that undergoes default argument promotion.
This helps cover some more of the CERT secure coding rule EXP58-CPP. Pass an object of the correct type to va_start (https://www.securecoding.cert.org/confluence/display/cplusplus/EXP58-CPP.+Pass+an+object+of+the+correct+type+to+va_start).

llvm-svn: 267338
2016-04-24 13:30:21 +00:00
Richard Trieu 891f0f176c Revert the bool portion of r267054
Remove the floating point to bool conversion warnings.  Some of these
conversions will be caught by -Wliteral-conversion and -Wfloat-conversion

llvm-svn: 267234
2016-04-22 22:14:32 +00:00
Richard Trieu be234c30ad Split interesting warnings off from -Wfloat-conversion
Restructure the implict floating point to integer conversions so that
interesting sub-groups are under different flags.  Breakdown of warnings:

No warning:
Exact conversions from floating point to integer:
int x = 10.0;
int x = 1e10;

-Wliteral-conversion - Floating point literal to integer with rounding:
int x = 5.5;
int x = -3.4;

-Wfloat-conversion - All conversions not covered by the above two:
int x = GetFloat();
int x = 5.5 + 3.5;

-Wfloat-zero-conversion - The expression converted has a non-zero floating
point value that gets converted to a zero integer value, excluded the cases
falling under -Wliteral-conversion.  Subset of -Wfloat-conversion.
int x = 1.0 / 2.0;

-Wfloat-overflow-conversion - The floating point value is outside the range
of the integer type, exluding cases from -Wliteral conversion.  Subset of
-Wfloat-conversion.
char x = 500;
char x = -1000;

-Wfloat-bool-conversion - Any conversion of a floating point type to bool.
Subset of -Wfloat-conversion.
if (GetFloat()) {}
bool x = 5.0;

-Wfloat-bool-constant-conversion - Conversion of a compile time evaluatable
floating point value to bool.  Subset of -Wfloat-bool-conversion.
bool x = 1.0;
bool x = 4.0 / 20.0;

Also add EvaluateAsFloat to Sema, which is similar to EvaluateAsInt, but for
floating point values.

llvm-svn: 267054
2016-04-21 21:04:55 +00:00
Serge Pavlov 7dcc97e7ac Warn if function or variable cannot be implicitly instantiated
With this patch compiler emits warning if it tries to make implicit instantiation
of a template but cannot find the template definition. The warning can be suppressed
by explicit instantiation declaration or by command line options
-Wundefined-var-template and -Wundefined-func-template. The implementation follows
the discussion of http://reviews.llvm.org/D12326.

Differential Revision: http://reviews.llvm.org/D16396

llvm-svn: 266719
2016-04-19 06:19:52 +00:00
Faisal Vali 5e9e8ac432 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.

llvm-svn: 266561
2016-04-17 17:32:04 +00:00
Nemanja Ivanovic d7d45bf8ce 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).

llvm-svn: 266460
2016-04-15 18:04:13 +00:00
Nico Weber 917fc9d7cb Revert r266415, it broke parsing SDK headers (PR27367).
llvm-svn: 266431
2016-04-15 14:35:06 +00:00
Andrey Bokhanko f7fa634887 [MSVC Compat] Implementation of __unaligned (MS extension) as a type qualifier
This patch implements __unaligned as a type qualifier; before that, it was
modeled as an attribute. Proper mangling of __unaligned is implemented as well.
Some OpenCL code/tests are tangenially affected, as they relied on existing
number and sizes of type qualifiers.

Differential Revision: http://reviews.llvm.org/D18596

llvm-svn: 266415
2016-04-15 08:03:51 +00:00
Charles Li 1a88adbb27 Lit C++11 Compatibility Patch #8
24 tests have been updated for C++11 compatibility.

llvm-svn: 266387
2016-04-14 23:47:07 +00:00
Dmitry Polukhin 9d64f72640 [MSVC] Fix check for wchar_t type in case of -fno-wchar
The example below should work identically with and without compiler native
wchar_t support.

void foo(wchar_t * t = L"");

Differential Revision: http://reviews.llvm.org/D19056

llvm-svn: 266287
2016-04-14 09:52:06 +00:00
Charles Li 64a1a81e76 Lit C++11 Compatibility Patch #7
13 tests have been updated for C++11 compatibility.
Differential Revision: http://reviews.llvm.org/D19068

llvm-svn: 266239
2016-04-13 20:00:45 +00:00
Nemanja Ivanovic 50f29e06a1 Enable support for __float128 in Clang
This patch corresponds to review:
http://reviews.llvm.org/D15120

It adds support for the __float128 keyword, literals and a target feature to
enable it. This support is disabled by default on all targets and any target
that has support for this type is free to add it.

Based on feedback that I've received from target maintainers, this appears to
be the right thing for most targets. I have not heard from the maintainers of
X86 which I believe supports this type. I will subsequently investigate the
impact of enabling this on X86.

llvm-svn: 266186
2016-04-13 09:49:45 +00:00
Richard Trieu 729c8e9793 Adjust tests to have consistent integer sizes.
Add a triple to the run lines so that integers will the same sizes across runs.
Also add a compile time check to ensure the assumptions about sizes are met.

llvm-svn: 265991
2016-04-11 20:37:04 +00:00
Richard Trieu 265c344ef8 Fix a crash on invalid with template handling
This is a fix for https://llvm.org/bugs/show_bug.cgi?id=25561 which was a
crash on invalid.  Change the handling of invalid decls to have a catch-all
case to prevent unexpecting decls from triggering an assertion.

llvm-svn: 265467
2016-04-05 21:13:54 +00:00
Richard Trieu 1c7237ae61 Fix -Wdynamic-class-memaccess to skip invalid classes.
This warning sometimes will infinitely recurse on CXXRecordDecl's from
ill-formed recursive classes that have fields of themselves.  Skip processing
these classes to prevent this from happening.
Fixes https://llvm.org/bugs/show_bug.cgi?id=27142

llvm-svn: 264991
2016-03-31 04:18:07 +00:00
George Burgess IV 21d3bffe29 [Sema] Fix PR27122: ICE with enable_if+ill-formed call.
In some cases, when we encounter a direct function call with an
incorrect number of arguments, we'll emit a diagnostic, and pretend that
the call to the function was valid. For example, in C:

int foo();
int a = foo(1);

Prior to this patch, we'd get an ICE if foo had an enable_if attribute,
because CheckEnableIf assumes that the number of arguments it gets
passed is valid for the function it's passed. Now, we check that the
number of args looks valid prior to checking enable_if conditions.

This fix was not done inside of CheckEnableIf because the problem
presently can only occur in one caller of CheckEnableIf (ActOnCallExpr).
Additionally, checking inside of CheckEnableIf would make us emit
multiple diagnostics for the same error (one "enable_if failed", one
"you gave this function the wrong number of arguments"), which seems
worse than just complaining about the latter.

llvm-svn: 264975
2016-03-31 00:16:25 +00:00
Vassil Vassilev bab6f96fff Canonicalize UnaryTransformType types when they don't have a known underlying type.
Fixes https://llvm.org/bugs/show_bug.cgi?id=26014

Reviewed by Richard Smith.

llvm-svn: 264937
2016-03-30 22:18:29 +00:00
Faisal Vali a734ab9808 [Cxx1z-constexpr-lambda-P0170R1] Support parsing of constexpr specifier (and its inference) on lambda expressions
Support the constexpr specifier on lambda expressions - and support its inference from the lambda call operator's body.

i.e.
  auto L = [] () constexpr { return 5; };
  static_assert(L() == 5); // OK
  auto Implicit = [] (auto a) { return a; };
  static_assert(Implicit(5) == 5); 

We do not support evaluation of lambda's within constant expressions just yet.

Implementation Strategy:
  - teach ParseLambdaExpressionAfterIntroducer to expect a constexpr specifier and mark the invented function call operator's declarator's decl-specifier with it; Have it emit fixits for multiple decl-specifiers (mutable or constexpr) in this location.
  - for cases where constexpr is not explicitly specified, have buildLambdaExpr check whether the invented function call operator satisfies the requirements of a constexpr function, by calling CheckConstexprFunctionDecl/Body.

Much obliged to Richard Smith for his patience and his care, in ensuring the code is clang-worthy.

llvm-svn: 264513
2016-03-26 16:11:37 +00:00
Richard Smith 0e32c5283a Don't warn on "use" of undefined inline function that isn't actually an ODR
use. In order for this to fire, the function needed to be a templated function
marked 'constexpr' and declared but not defined. This weird pattern appears in
libstdc++'s alloc_traits.h.

llvm-svn: 264471
2016-03-25 22:29:27 +00:00
Richard Smith d6a04d79c7 Store list of undefined-but-used objects in a deterministic order to fix
non-deterministic diagnostics (and non-deterministic PCH files). Check these
when building a module rather than serializing it; it's not reasonable for a
module's use to be satisfied by a definition in the user of the module.

llvm-svn: 264466
2016-03-25 21:49:43 +00:00
Richard Smith 95853077c3 Fix nondeterminism in computation of builtin operator overload sets.
llvm-svn: 264363
2016-03-25 00:08:53 +00:00
Richard Smith 6642bb3337 Change ADL to produce lookup results in a deterministic order. This fixes some
rare issues with nondeterministic diagnostic order, and some very common issues
with nondeterministic module builds.

llvm-svn: 264323
2016-03-24 19:12:22 +00:00
Richard Smith fd55fc86ed Make SemaAccess smarter about determining when a dependent class might
instantiate to match a friend class declaration. It's still pretty dumb,
though.

llvm-svn: 264189
2016-03-23 20:39:06 +00:00
Richard Smith c7649dc749 Make sure to perform dependent access checks when instantiating a
lambda-expression. We don't actually instantiate the closure type / operator()
in the template in order to produce the closure type / operator() in the
instantiation, so this isn't caught by the normal path.

llvm-svn: 264184
2016-03-23 20:07:07 +00:00
Manman Ren 75bc676160 Add replacement = "xxx" to AvailabilityAttr.
This commit adds a named argument to AvailabilityAttr, while r263652 adds an
optional string argument to __attribute__((deprecated)).

This was commited in r263687 and reverted in 263752 due to misaligned
access.

rdar://20588929

llvm-svn: 263958
2016-03-21 17:30:55 +00:00
Faisal Vali dc6b596ebb [Cxx1z] Implement Lambda Capture of *this by Value as [=,*this] (P0018R3)
Implement lambda capture of *this by copy.
For e.g.:
struct A {

  int d = 10;
  auto foo() { return [*this] (auto a) mutable { d+=a; return d; }; }

};

auto L = A{}.foo(); // A{}'s lifetime is gone.

// Below is still ok, because *this was captured by value.
assert(L(10) == 20);
assert(L(100) == 120);

If the capture was implicit, or [this] (i.e. *this was captured by reference), this code would be otherwise undefined.

Implementation Strategy:
  - amend the parser to accept *this in the lambda introducer
  - add a new king of capture LCK_StarThis
  - teach Sema::CheckCXXThisCapture to handle by copy captures of the
    enclosing object (i.e. *this)
  - when CheckCXXThisCapture does capture by copy, the corresponding 
    initializer expression for the closure's data member 
    direct-initializes it thus making a copy of '*this'.
  - in codegen, when assigning to CXXThisValue, if *this was captured by 
    copy, make sure it points to the corresponding field member, and
    not, unlike when captured by reference, what the field member points
    to.
  - mark feature as implemented in svn

Much gratitude to Richard Smith for his carefully illuminating reviews!   

llvm-svn: 263921
2016-03-21 09:25:37 +00:00
George Burgess IV cc2f355f71 [Sema] Make type deduction work with some overloadable functions
Some functions can't have their address taken. If we encounter an
overload set where only one of the candidates can have its address
taken, we should automatically select that candidate's type in type
deduction.

Differential Revision: http://reviews.llvm.org/D15591

llvm-svn: 263888
2016-03-19 21:51:45 +00:00
George Burgess IV 3cde9bf9d5 [Sema] Allow casting of some overloaded functions
Some functions can't have their address taken. If we encounter an
overload set where only one of the candidates can have its address
taken, we should automatically select that candidate in cast
expressions.

Differential Revision: http://reviews.llvm.org/D17701

llvm-svn: 263887
2016-03-19 21:36:10 +00:00
Manman Ren 34888f86ef Revert r263687 for ubsan bot failure.
llvm-svn: 263752
2016-03-17 22:13:50 +00:00
Manman Ren a7c4760c8e Add an optional named argument (replacement = "xxx") to AvailabilityAttr.
This commit adds a named argument to AvailabilityAttr, while r263652 adds an
optional string argument to __attribute__((deprecated)). This enables the
compiler to provide Fix-Its for deprecated declarations.

rdar://20588929

llvm-svn: 263687
2016-03-17 03:09:55 +00:00
Manman Ren c7890fed01 Add an optional string argument to DeprecatedAttr for Fix-It.
We only add this to __attribute__((deprecated)).

Differential Revision: http://reviews.llvm.org/D17865

llvm-svn: 263652
2016-03-16 18:50:49 +00:00
Olivier Goffart b94ed61452 Fix destructor definition of invalid classes
The declaration of the destructor of an invalid class was not properly marked
as noexcept. As a result, the definition of the same destructor, which was
properly implicitly marked as noexcept, would not match the definition.
This would cause the definition CXXDestructorDecl to be matked as invalid
and omited from the AST.

Differential Revision: http://reviews.llvm.org/D17988

llvm-svn: 263639
2016-03-16 14:36:11 +00:00
Bob Wilson 57819fc809 Move the fixit for -Wformat-security to a note.
r263299 added a fixit for the -Wformat-security warning, but that runs
into complications with our guideline that error recovery should be done
as-if the fixit had been applied. Putting the fixit on a note avoids that.

llvm-svn: 263584
2016-03-15 20:56:38 +00:00
Richard Smith 4d3d785e3f Add test for r263138.
llvm-svn: 263155
2016-03-10 19:22:21 +00:00
Dmitry Polukhin bf17ecf59a [GCC] PR23529 Sema part of attrbute abi_tag support
Original patch by Stefan Bühler http://reviews.llvm.org/D12834

Difference between original and this one:
- fixed all comments in original code review
- added more tests, all new diagnostics now covered by tests
- moved abi_tag on re-declaration checks to Sema::mergeDeclAttributes
  where they actually may work as designed
- clang-format + other stylistic changes

Mangle part will be sent for review as a separate patch.

Differential Revision: http://reviews.llvm.org/D17567

llvm-svn: 263015
2016-03-09 15:30:53 +00:00
Richard Smith bbbe618467 Fix crash in access check for aggregate initialization of base classes. It's
not obvious how to access-check these, so pick a conservative rule until we get
feedback from CWG.

llvm-svn: 262966
2016-03-08 23:17:35 +00:00
Richard Smith 872307e2ac P0017R1: In C++1z, an aggregate class can have (public non-virtual) base classes; these are initialized as if they were data members.
llvm-svn: 262963
2016-03-08 22:17:41 +00:00
Duncan P. N. Exon Smith 8536392a83 Sema: Methods in unavailable classes are unavailable
Similar to the template cases in r262050, when a C++ method in an
unavailable struct/class calls unavailable API, don't diagnose an error.
I.e., this case was failing:

    void foo() __attribute__((unavailable));
    struct __attribute__((unavailable)) A {
      void bar() { foo(); }
    };

Since A is unavailable, A::bar is allowed to call foo.  However, we were
emitting a diagnostic here.  This commit checks up the context chain
from A::bar, in a manner inspired by SemaDeclAttr.cpp:isDeclUnavailable.

I expected to find other related issues but failed to trigger them:

- I wondered if DeclBase::getAvailability should check for
  `TemplateDecl` instead of `FunctionTemplateDecl`, but I couldn't find
  a way to trigger this.  I left behind a few extra tests to make sure
  we don't regress.

- I wondered if Sema::isFunctionConsideredUnavailable should be
  symmetric, checking up the context chain of the callee (this commit
  only checks up the context chain of the caller).  However, I couldn't
  think of a testcase that didn't require first referencing the
  unavailable type; this, we already diagnose.

rdar://problem/25030656

llvm-svn: 262921
2016-03-08 10:28:52 +00:00
Richard Smith e513cd25bd Move [[nodiscard]] tests into test/CXX tree.
llvm-svn: 262888
2016-03-08 00:44:49 +00:00
Richard Smith d5d796ecde Define __has_cpp_attribute(fallthrough) to a more reasonable value. (What year is it?!)
llvm-svn: 262887
2016-03-08 00:40:32 +00:00
Richard Smith 4f902c7ecc P0188R1: add support for standard [[fallthrough]] attribute. This is almost
exactly the same as clang's existing [[clang::fallthrough]] attribute, which
has been updated to have the same semantics. The one significant difference
is that [[fallthrough]] is ill-formed if it's not used immediately before a
switch label (even when -Wimplicit-fallthrough is disabled). To support that,
we now build a CFG of any function that uses a '[[fallthrough]];' statement
to check.

In passing, fix some bugs with our support for statement attributes -- in
particular, diagnose their use on declarations, rather than asserting.

llvm-svn: 262881
2016-03-08 00:32:55 +00:00
Aaron Ballman e7964789da Implement support for [[nodiscard]] in C++1z that is based off existing support for warn_unused_result, and treat it as an extension pre-C++1z. This also means extending the existing warn_unused_result attribute so that it can be placed on an enum as well as a class.
llvm-svn: 262872
2016-03-07 22:44:55 +00:00
Richard Trieu 2334a30e15 Add null check to diagnostic path for lambda captures.
Previously, the failed capture of a variable in nested lambdas may crash when
the lambda pointer is null.  Only give the note if a location can be retreived
from the lambda pointer.

llvm-svn: 262765
2016-03-05 04:04:57 +00:00
David Blaikie ac92893a93 PR5941 - improve diagnostic for * vs & confusion when choosing overload candidate with a parameter of incomplete (ref or pointer) type
Reviewers: dblaikie

Differential Revision: http://reviews.llvm.org/D16949

llvm-svn: 262752
2016-03-04 22:29:11 +00:00
John McCall 477f2bb0d5 Semantic analysis for the swiftcall calling convention.
I've tried to keep the infrastructure behind parameter ABI
treatments fairly general.

llvm-svn: 262587
2016-03-03 06:39:32 +00:00
John McCall 3b5a8f5ffc Improve some infrastructure for extended parameter infos and
fix a bug with the instantiation of ns_consumed parameter
attributes in ARC.

llvm-svn: 262551
2016-03-03 00:10:03 +00:00
Richard Smith e5a91464bc Fix bug in using shadow decl checking: a using shadow decl should not conflict
with a prior UsingDecl -- those should not even really be found by the lookup
here, except that we use the same lookup results for two different checks, and
the other check needs them.

This happens to work in *almost all* cases, because either the lookup results
list the UsingDecl first (and the NonTag result gets replaced by something
else) or because the problematic declaration is a function (which causes us to
use different logic to detect conflicts). This can also be triggered from a
state only reachable through modules (where the name lookup results can contain
multiple UsingDecls in the same scope).

llvm-svn: 262105
2016-02-27 02:36:43 +00:00
Paul Robinson 65ab102be3 Fix Clang tests that used CHECK-NEXT-NOT and CHECK-DAG-NOT.
FileCheck actually doesn't support combo suffixes.

Differential Revision: http://reviews.llvm.org/D17589

llvm-svn: 262052
2016-02-26 19:34:01 +00:00
Duncan P. N. Exon Smith ec599a906b SemaCXX: Support templates in availability attributes
If the availability context is `FunctionTemplateDecl`, we should look
through it to the `FunctionDecl`.  This prevents a diagnostic in the
following case:

    class C __attribute__((unavailable));
    template <class T> void foo(C&) __attribute__((unavailable));

This adds tests for availability in templates in many other cases, but
that was the only case that failed before this patch.

I added a feature `__has_feature(attribute_availability_in_templates)`
so users can test for this.

rdar://problem/24561029

llvm-svn: 262050
2016-02-26 19:27:00 +00:00
David Majnemer e9807b28af [MSVC Compat] Don't evaluate member base expressions w/o side effects
A member expression's base doesn't always have an impact on what the
member decl would evaluate to.  In such a case, the base is used as a
poor man's scope qualifier.

This fixes PR26738.

Differential Revision: http://reviews.llvm.org/D17619

llvm-svn: 261975
2016-02-26 04:23:19 +00:00
Nico Weber 72c57f49c4 Fix rejects-valid caused by r261297.
r261297 called hasUserProvidedDefaultConstructor() to check if defining a
const object is ok.  This is incorrect for this example:

  struct X { template<typename ...T> X(T...); int n; };
  const X x; // formerly OK, now bogus error

Instead, track if a class has a defaulted default constructor, and disallow
a const object for classes that either have defaulted default constructors or
if they need an implicit constructor.

Bug report and fix approach by Richard Smith, thanks!

llvm-svn: 261770
2016-02-24 20:58:14 +00:00
Faisal Vali e7f8fb9835 Fix PR24473 : Teach clang to remember to substitute into member variable templates referred to within dependent qualified ids.
In passing also fix a semi-related bug that allows access to variable templates through member access notation.

llvm-svn: 261506
2016-02-22 02:24:29 +00:00
David Majnemer c919f5f964 Correct typos after acting on invalid subscript expressions
llvm-svn: 261312
2016-02-19 07:15:33 +00:00
Nico Weber 6a6376b17c Implement the likely resolution of core issue 253.
C++11 requires const objects to have a user-provided constructor, even for
classes without any fields. DR 253 relaxes this to say "If the implicit default
constructor initializes all subobjects, no initializer should be required."

clang is currently the only compiler that implements this C++11 rule, and e.g.
libstdc++ relies on something like DR 253 to compile in newer versions.  This
change  makes it possible to build code that says `const vector<int> v;' again
when using libstdc++5.2 and _GLIBCXX_DEBUG
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60284).

Fixes PR23381.

http://reviews.llvm.org/D16552

llvm-svn: 261297
2016-02-19 01:52:46 +00:00
Reid Kleckner bde5ede526 [Sema] PR25181 Fix crash when method declaration with throw spec fails to parse correctly
Fixes crash referenced in PR25181 where dyn_cast is called on a null
instance of LM.Method.

Reviewers: majnemer, rnk

Patch by Don Hinton

Differential Revision: http://reviews.llvm.org/D17072

llvm-svn: 261292
2016-02-19 01:15:08 +00:00
Richard Trieu faca2d83b1 Add -Wcomma warning to Clang.
-Wcomma will detect and warn on most uses of the builtin comma operator.  It
currently whitelists the first and third statements of the for-loop.  For other
cases, the warning can be silenced by casting the first operand of the comma
operator to void.

Differential Revision: http://reviews.llvm.org/D3976

llvm-svn: 261278
2016-02-18 23:58:40 +00:00
David Majnemer bc24cb5fb5 [Parse] Make sure we don't forget to diagnose typos in exprs
If ActOn*Op fails, we will forget to diagnose typos in the LHS of
expressions.

llvm-svn: 261191
2016-02-18 06:37:44 +00:00
David Majnemer 2eb74e278d Correct more typos in conditional expressions
We didn't correctly handle some edge cases, causing us to bail out
before correcting all the typos.

llvm-svn: 261109
2016-02-17 17:19:00 +00:00
Richard Smith c28aee6a51 Improve diagnostics for ill-formed literal operator declarations.
Patch by Erik Pilkington!

llvm-svn: 261034
2016-02-17 00:04:04 +00:00
Reid Kleckner 4ce625c814 [typo-correction] Apply name specifier corrections when forming a NNS
Previously we would leave behind the old name specifier prefix, which
creates an invalid AST.  Other callers of CorrectTypo update their
CXXScopeSpec objects with the correction specifier if one is present.

llvm-svn: 260993
2016-02-16 19:16:20 +00:00
Andrey Bokhanko c4feaf0272 PR26449: Tests for builtin_classify_type fix
In my previous commit (rL260881) I forget to svn add tests. This commit adds
them.

Differential Revision: http://reviews.llvm.org/D16846

llvm-svn: 260882
2016-02-15 10:44:27 +00:00
Saleem Abdulrasool cfd4553a7c Sema: prevent assertion on stack return checking
In the case that the array indexing itself is within a type dependent context,
bail out of the evaluation.  We would previously try to symbolically evaluate
the expression which would then try to evaluate a non-address expression as an
address, triggering an assertion in Asserts builds.

We only need to consider the array subscript expression itself as in the case
that the base itself being type dependent is handled appropriately in EvalAddr.

Resolves PR26599.

llvm-svn: 260867
2016-02-15 01:51:24 +00:00
Richard Trieu 0a5e166a0b Make -Wnull-conversion more useful.
When a null constant is used in a macro, walk through the macro stack to
determine where the null constant is written and where the context is located.
Only warn if both locations are within the same macro expansion.  This helps
function-like macros which involve pointers be treated as if they were
functions.

llvm-svn: 260776
2016-02-13 00:58:53 +00:00
Olivier Goffart 8bc0caa2e9 Fix ICE with constexpr and friend functions
Fix a crash while parsing this code:

  struct X  {
    friend constexpr int foo(X*) { return 12; }
    static constexpr int j = foo(static_cast<X*>(nullptr));
  };

Differential Revision: http://reviews.llvm.org/D16973

llvm-svn: 260675
2016-02-12 12:34:44 +00:00
Manman Ren b4e8a1b308 Fix a crash when there is a typo in the return statement.
If the typo happens after a successful deduction for an earlier
return statement, we should check if the deduced type is null
before using it.

The typo correction happens after we try to deduce the return
type and we ignore the deduction from the typo and continue
to typo correction.

rdar://24342247

llvm-svn: 259820
2016-02-04 20:05:40 +00:00
Douglas Gregor 0fc3a00168 [Sema debugger support] Require non-void types to be complete in unknown-anytype casts.
When performing a cast from an __unknown_anytype function call to a
non-void type, we need to make sure that type is complete. Fixes
rdar://problem/23959960.

llvm-svn: 259681
2016-02-03 19:13:08 +00:00
Richard Smith 59b982e1be PR24989: Stop trying to use the C++11 rules for lambda return type inference in
C++14 generic lambdas. It conflicts with the C++14 return type deduction
mechanism, and results in us failing to actually deduce the lambda's return
type in some cases.

llvm-svn: 259609
2016-02-02 23:58:56 +00:00
Denis Zobnin d9e2dcdb42 Fix for PR8901: attribute "mode" rejected for enums and dependent types.
Allow "mode" attribute for enum types, except for vector modes, for compatibility with GCC.
Support "mode" attribute with dependent types.

Differential Revision: http://reviews.llvm.org/D16219

llvm-svn: 259497
2016-02-02 13:50:39 +00:00
David Majnemer 31be598153 Mark DR1250 as implemented
We implemented this DR back in r258768 but forgot to mark it as
implemented.

llvm-svn: 259335
2016-02-01 01:33:17 +00:00
Argyrios Kyrtzidis b4030df780 [SemaCXX] Fix crash-on-invalid while trying to deduce return type of a lambda.
rdar://22032373

llvm-svn: 259287
2016-01-30 01:51:20 +00:00
Richard Trieu 3a5c958182 Fix -Wnull-conversion for long macros.
Move the function to get a macro name from DiagnosticRenderer.cpp to Lexer.cpp
so that other files can use it.  Lexer now has two functions to get the
immediate macro name, the newly added one is better for diagnostic purposes.
Make -Wnull-conversion use this function for better NULL macro detection.

llvm-svn: 258778
2016-01-26 02:51:55 +00:00
David Majnemer d3d91bd17f [Sema] Incomplete types are OK for covariant returns
Per C++14 [class.virtual]p8, it is OK for the return type's class type
to be incomplete so long as the return type is the same between the base
and complete classes.

This fixes PR26297.

llvm-svn: 258768
2016-01-26 01:37:01 +00:00
Nico Weber 5a9259caa9 Make -Wdelete-non-virtual-dtor warn on explicit `a->~A()` dtor calls too.
-Wdelete-non-virtual-dtor warns if A is a type with virtual functions but
without virtual dtor has its constructor called via `delete a`. This makes the
warning also fire if the dtor is called via `a->~A()`. This would've found a
security bug in Chromium at compile time. Fixes PR26137.

To fix the warning, add a virtual destructor, make the class final, or remove
its other virtual methods.  If you want to silence the warning, there's also
a fixit that shows how:

test.cc:12:3: warning: destructor called on 'B' ... [-Wdelete-non-virtual-dtor]
  b->~B();
  ^
test.cc:12:6: note: qualify call to silence this warning
  b->~B();
     ^
     B::

http://reviews.llvm.org/D16206

llvm-svn: 257939
2016-01-15 21:45:31 +00:00
Alexey Bataev d51e9933b6 [X86] Support 'interrupt' attribute for x86
This attribute may be attached to a function definition and instructs the backend to generate appropriate function entry/exit code so that
it can be used directly as an interrupt handler.
The IRET instruction, instead of the RET instruction, is used to return from interrupt or exception handlers. All registers, except for the EFLAGS register which is restored by the IRET instruction, are preserved by the compiler.
Any interruptible-without-stack-switch code must be compiled with -mno-red-zone since interrupt handlers can and will, because of the hardware design, touch
the red zone.

interrupt handler must be declared with a mandatory pointer argument:
struct interrupt_frame;

__attribute__ ((interrupt))
void f (struct interrupt_frame *frame) {
    ...
}
and user must properly define the structure the pointer pointing to.

exception handler: 

The exception handler is very similar to the interrupt handler with a different mandatory function signature:
#ifdef __x86_64__
typedef unsigned long long int uword_t;
#else
typedef unsigned int uword_t;
#endif

struct interrupt_frame;

__attribute__ ((interrupt))
void f (struct interrupt_frame *frame, uword_t error_code) {
    ...
}
and compiler pops the error code off stack before the IRET instruction.

The exception handler should only be used for exceptions which push an error code and all other exceptions must use the interrupt handler.
The system will crash if the wrong handler is used.
Differential Revision: http://reviews.llvm.org/D15709

llvm-svn: 257867
2016-01-15 04:06:31 +00:00