Commit Graph

4106 Commits

Author SHA1 Message Date
Alex Lorenz cb642b9136 [Sema][TreeTransform] Re-create DesignatedInitExpr when a field designator
has no field declaration.

This commit fixes an invalid Winitializer-overrides warning that's shown
when analyzing a second (or any after the first) instantiation of a designated
initializer. This invalid warning is fixed by making sure that a
DesignatedInitExpr is rebuilt by the tree transformer when it has a field
designator whose FieldDecl* hasn't been yet initialized. This ensures that a
different DesignatedInitExpr is processed by Sema for every instantiation, and
thus the invalid warning is avoided.

rdar://28768441

Differential Revision: https://reviews.llvm.org/D25777

llvm-svn: 284959
2016-10-24 09:33:32 +00:00
Richard Smith 5e9746f520 DR583, DR1512: Implement a rewrite to C++'s 'composite pointer type' rules.
This has two significant effects:

1) Direct relational comparisons between null pointer constants (0 and nullopt)
   and pointers are now ill-formed. This was always the case for C, and it
   appears that C++ only ever permitted by accident. For instance, cases like
     nullptr < &a
   are now rejected.

2) Comparisons and conditional operators between differently-cv-qualified
   pointer types now work, and produce a composite type that both source
   pointer types can convert to (when possible). For instance, comparison
   between 'int **' and 'const int **' is now valid, and uses an intermediate
   type of 'const int *const *'.

Clang previously supported #2 as an extension.

We do not accept the cases in #1 as an extension. I've tested a fair amount of
code to check that this doesn't break it, but if it turns out that someone is
relying on this, we can easily add it back as an extension.

This is a re-commit of r284800.

llvm-svn: 284890
2016-10-21 22:00:42 +00:00
Renato Golin 41189656ed Revert "DR583, DR1512: Implement a rewrite to C++'s 'composite pointer type' rules."
This reverts commit r284800, as it failed all ARM/AArch64 bots.

llvm-svn: 284811
2016-10-21 08:03:49 +00:00
Richard Smith fdf0888b69 Don't try to use !Previous.empty() as a proxy for "Is this a redeclaration?" --
we don't collapse that down to a single entry if it's not a redeclaration.
Instead, set the Redeclaration bit on the Declarator to indicate whether a
function is a redeclaration (which may not have been linked into the
redeclaration chain if it's a dependent context friend).

Fixes a rejects-valid; see testcase.

llvm-svn: 284802
2016-10-21 03:15:03 +00:00
Richard Smith 0c1c53e3fa DR583, DR1512: Implement a rewrite to C++'s 'composite pointer type' rules.
This has two significant effects:

1) Direct relational comparisons between null pointer constants (0 and nullopt)
   and pointers are now ill-formed. This was always the case for C, and it
   appears that C++ only ever permitted by accident. For instance, cases like
     nullptr < &a
   are now rejected.

2) Comparisons and conditional operators between differently-cv-qualified
   pointer types now work, and produce a composite type that both source
   pointer types can convert to (when possible). For instance, comparison
   between 'int **' and 'const int **' is now valid, and uses an intermediate
   type of 'const int *const *'.

Clang previously supported #2 as an extension.

We do not accept the cases in #1 as an extension. I've tested a fair amount of
code to check that this doesn't break it, but if it turns out that someone is
relying on this, we can easily add it back as an extension.

llvm-svn: 284800
2016-10-21 02:36:37 +00:00
Richard Smith f70a906a11 [c++1z] Fix assertion failure when using the wrong number of bindings for a
struct with unnamed bitfields.

llvm-svn: 284761
2016-10-20 18:29:25 +00:00
Richard Smith 628954652f Extend hack to work around bad exception specifications for 'swap' members to
also cover libstdc++'s std::__debug::array and std::__profile::array.

llvm-svn: 284669
2016-10-19 23:47:37 +00:00
Richard Smith 5f4b388442 Resolve exception specifications when selecting an overloaded operator.
llvm-svn: 284556
2016-10-19 00:14:23 +00:00
Richard Smith 84a0b6dba1 DR1330: instantiate exception-specifications when "needed". We previously did
not instantiate exception specifications of functions if they were only used in
unevaluated contexts (other than 'noexcept' expressions).

In C++17 onwards, this becomes essential since the exception specification is
now part of the function's type.

Note that this means that constructs like the following no longer work:

  struct A {
    static T f() noexcept(...);
    decltype(f()) *p;
  };

... because the decltype expression now needs the exception specification of
'f', which has not yet been parsed.

llvm-svn: 284549
2016-10-18 23:39:12 +00:00
Richard Smith fccb5128b2 Add missing warning for use of C++1z init-statements in C++14 and before.
llvm-svn: 284530
2016-10-18 20:27:16 +00:00
Richard Smith 304b124a11 [c++1z] Fix corner case where we could create a function type whose canonical type is not actually canonical.
llvm-svn: 284528
2016-10-18 20:13:25 +00:00
Richard Smith 2a2cda58f8 When two function types have equivalent (but distinct) noexcept specifications, create separate type sugar nodes. This is necessary so that substitution into the exception specification will substitute into the correct expression.
llvm-svn: 284519
2016-10-18 19:29:18 +00:00
Richard Smith 99677afd54 [c++1z] Use canonical expression equivalence to determine whether two different
dependent noexcept specifications result in the same canonical function type.

We still use non-canonical hashing when deduplicating type sugar so that
diagnostics will point to the right place.

llvm-svn: 284457
2016-10-18 06:47:03 +00:00
Richard Smith 3c4f8d2e96 P0012R1: Make exception specifications be part of the type system. This
implements the bulk of the change (modifying the type system to include
exception specifications), but not all the details just yet.

llvm-svn: 284337
2016-10-16 17:54:23 +00:00
Douglas Katzman 3ed0f643fc Implement no_sanitize_address for global vars
llvm-svn: 284272
2016-10-14 19:55:09 +00:00
Alex Lorenz 757a69b760 [Sema] Handle transparent_union attributes in C mode only
This commit marks the transparent_union attributes as C only because clang
doesn't support them in C++ mode. Prior to this commit, clang still tried to
verify these attributes in C++, leading to crashes when analyzing templated
transparent_union unions that have dependent field types. This commit ensures
that such crashes won't happen again.

As a result of this commit clang now displays a warning every time it encounters
a transparent_union attribute in C++ mode.

Differential Revision: https://reviews.llvm.org/D25308

llvm-svn: 283995
2016-10-12 09:36:35 +00:00
Arnold Schwaighofer 5bb08d8f5a Swift Calling Convention: Parameters are allowed after the
swift_error/swift_context parameter

We need to be able to decelare witness functions which append the self type and
the self witness tables at the end of the parameter list.

rdar://28720996

llvm-svn: 283933
2016-10-11 20:34:06 +00:00
Eric Fiselier 7ae80c6396 [Sema] Prevent using member declaration diagnostic if the base class is invalid.
Summary:
Once a base class has been made invalid (by a static_assert for example) all using-member declarations in the derived classes will result in a "not a base class" diagnostic. This diagnostic is very misleading and should not be emitted.

This change is needed to help libc++ produce reasonable diagnostics in `std::optional` and `std::variant`.  

Reviewers: rsmith, majnemer, aaron.ballman

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D25430

llvm-svn: 283755
2016-10-10 14:26:40 +00:00
Richard Smith e15a370084 PR25890: Fix incoherent error handling in PerformImplicitConversion and
CheckSingleAssignmentConstraints. These no longer produce ExprError() when they
have not emitted an error, and reliably inform the caller when they *have*
emitted an error.

This fixes some serious issues where we would fail to emit any diagnostic for
invalid code and then attempt to emit code for an invalid AST, and conversely
some issues where we would emit two diagnostics for the same problem.

llvm-svn: 283508
2016-10-06 23:12:58 +00:00
Eric Fiselier 9813131936 [coroutines] Fix co_return statement for initializer list arguments
Summary:
Previously the statement `co_return {42}` would be transformed into `P.return_void()`, since the type of `{42}` is represented as `void` by Clang.

This patch fixes the bug by checking for `InitListExpr` arguments and transforming them accordingly.

Reviewers: majnemer, GorNishanov, rsmith

Subscribers: mehdi_amini, cfe-commits

Differential Revision: https://reviews.llvm.org/D25296

llvm-svn: 283495
2016-10-06 21:23:38 +00:00
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