Commit Graph

1950 Commits

Author SHA1 Message Date
Richard Smith afe48f9d68 Fold -Wreturn-stack-address into general initialization lifetime
checking.

llvm-svn: 337743
2018-07-23 21:21:22 +00:00
Erik Pilkington 0b75dc5fa2 [Sema] Diagnose an invalid dependent function template specialization
Previously, clang marked the specialization as invalid without emitting a
diagnostic. This lead to an assert in CodeGen.

rdar://41806724

Differential revision: https://reviews.llvm.org/D49085

llvm-svn: 337497
2018-07-19 20:40:20 +00:00
Richard Smith 5407d4f9be DR330: when determining whether a cast casts away constness, consider
qualifiers from all levels matching a multidimensional array.

For example, this allows casting from
  pointer to       array of            array of   const volatile int
to
  pointer to const pointer to volatile pointer to                int
because the multidimensional array part of the source type corresponds
to a part of the destination type that contains both 'const' and
'volatile'.

Differential Revision: https://reviews.llvm.org/D49457

llvm-svn: 337422
2018-07-18 20:13:36 +00:00
Richard Smith d87aab939a Restructure checking for, and warning on, lifetime extension.
This change implements C++ DR1696, which makes initialization of a
reference member of a class from a temporary object ill-formed. The
standard wording here is imprecise, but we interpret it as meaning that
any time a mem-initializer would result in lifetime extension, the
program is ill-formed.

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

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

The error message is

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

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

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

llvm-svn: 337226
2018-07-17 00:11:41 +00:00
Richard Smith c379d1a424 PR38136: improve handling of template argument deduction of non-trailing
function parameter packs.

This makes our handling of non-trailing function parameter packs
consistent between the case of deduction at the top level in a function
call and other cases where deduction encounters a non-trailing function
parameter pack.

Instead of treating a non-trailing pack and all later parameters as
being non-deduced, we treat a non-trailing pack as exactly matching
any explicitly-specified template arguments (or being an empty pack
if there are no such arguments). This corresponds to the "never deduced"
rule in [temp.deduct.call]p1, but generalized to all deduction contexts.

Non-trailing template argument packs still result in the entire
template argument list being treated as non-deduced, as specified in
[temp.deduct.type]p9.

llvm-svn: 336962
2018-07-12 23:32:39 +00:00
Richard Smith b64764a30b PR38141: check whether noexcept-specifications are equivalent in redeclarations
llvm-svn: 336946
2018-07-12 21:11:25 +00:00
Richard Smith 746e35e8a1 Add tests for function conversions in conversion function template
deduction.

llvm-svn: 336931
2018-07-12 18:49:13 +00:00
Nicolas Lesser b6d5c58718 [C++17] Disallow lambdas in template parameters (PR33696).
Summary: This revision disallows lambdas in template parameters, as reported in PR33696.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D37442

llvm-svn: 336930
2018-07-12 18:45:41 +00:00
Richard Smith b884ed186e Fix deduction for conversion function templates converting to reference
types.

We previously tried to use the "parameter is a reference" logic here,
but that doesn't work because it gets P and A backwards. Instead, add
a separate implementation of the "deduced A can be less qualified than
A" rule.

This also exposes that we incorrectly stripped cv-qualifiers from the
referent of A if it was a reference. However, if we don't do that, we
get the wrong results when P is a reference. In an attempt to match
what sanity dictates and what other implementations are doing, we now
remove cv-qualifiers from A and P unless both are reference types. I've
brought this up on the core reflector too, to try to get the standard
fixed.

llvm-svn: 336867
2018-07-11 23:19:41 +00:00
Richard Smith 34c325028a Fix determination of whether one set of cvr-qualifiers is compatible
with another in template argument deduction.

We happened to typically get away with getting this wrong, because the
cases where we'd produce a bogus deduction were caught by the final
"deduced A is compatible with A" check.

llvm-svn: 336852
2018-07-11 21:07:04 +00:00
Richard Smith a3405ffcec DR330: look through array types when forming the cv-decomposition of a type.
This allows more qualification conversions, eg. conversion from
   'int *(*)[]' -> 'const int *const (*)[]'
is now permitted, along with all the consequences of that: more types
are similar, more cases are permitted by const_cast, and conversely,
fewer "casting away constness" cases are permitted by reinterpret_cast.

llvm-svn: 336745
2018-07-11 00:19:19 +00:00
Richard Smith f276e2dc46 Fix determination of whether a reinterpret_cast casts away constness.
The "casts away constness" check doesn't care at all how the different
layers of the source and destination type were formed: for example, if
the source is a pointer and the destination is a pointer-to-member, the
types are still decomposed and their pointee qualifications are still
checked.

This rule is bizarre and somewhat ridiculous, so as an extension we
accept code making use of such reinterpret_casts with a warning outside
of SFINAE contexts.

llvm-svn: 336738
2018-07-10 23:04:35 +00:00
Richard Smith b368ea865f Per C++ [over.match.copy]p1, direct-initialization of a reference can
only invoke converting constructors of the reference's underlying type.

llvm-svn: 336153
2018-07-02 23:25:22 +00:00
Richard Smith eb3b5b6fd2 Specify an explicit underlying type for this enum to fix Windows
buildbots.

On Windows targets, enums always get an underlying type of 'int', even
if they have wider enumerators. (This is non-conforming, but it's
effectively part of the target ABI.)

llvm-svn: 336013
2018-06-29 20:41:23 +00:00
Richard Smith aadb254a79 PR37979: integral promotions in C++ treat enum bit-fields like enums,
not like bit-fields.

We used to get this right "by accident", because conversions for the
selected built-in overloaded operator would convert the enum bit-field
to its corresponding underlying type early. But after DR1687 that no
longer happens.

Technically this change should also apply to C, where bit-fields only
have special promotion rules if the bit-field's declared type is
_Bool, int, signed int, or unsigned int, but for GCC compatibility we
only look at the bit-width and not the underlying type when performing
bit-field integral promotions in C.

llvm-svn: 335925
2018-06-28 21:17:55 +00:00
Richard Smith 1ef7554efd DR1687: When overload resolution selects a built-in operator, implicit
conversions are only applied to operands of class type, and the second
standard conversion sequence is not applied.

When diagnosing an invalid builtin binary operator, talk about the
original types rather than the converted types. If these differ by a
user-defined conversion, tell the user what happened.

llvm-svn: 335781
2018-06-27 20:30:34 +00:00
Richard Smith becac9eb56 DR1213: Ignore implicit conversions when determining if an operand of an
array subscript expression is an array prvalue.

Also apply DR1213 to vector prvalues for consistency.

llvm-svn: 335779
2018-06-27 20:29:32 +00:00
Richard Smith 69bc9aa22f Restore pre-r335182 behavior for naming inherited constructors as
members of dependent contexts.

This permits cases where the names before and after the '::' in a
dependent inherited constructor using-declaration do not match, but
where we can nonetheless tell when parsing the template that a
constructor is being named. Under (open) core language DR 2070, such
cases will probably be ill-formed, but r335182 does not quite give
that result and didn't intend to change this, so restore the old
behavior for now.

llvm-svn: 335381
2018-06-22 19:50:19 +00:00
Richard Smith 90ae9677e7 When a dependent alignas is applied to a non-dependent typedef,
prioritize the error for the bad subject over the error for the
dependent / non-dependent mismatch.

llvm-svn: 335191
2018-06-20 23:36:55 +00:00
Richard Smith 715ee079da Related to PR37768: improve diagnostics for class name shadowing.
Diagnose the name of the class being shadowed by using declarations, and
improve the diagnostics for the case where the name of the class is
shadowed by a non-static data member in a class with constructors.  In
the latter case, we now always give the "member with the same name as
its class" diagnostic regardless of the relative order of the member and
the constructor, rather than giving an inscrutible diagnostic if the
constructor appears second.

llvm-svn: 335182
2018-06-20 21:58:20 +00:00
Richard Smith c00e44656d [c++17] If a class inherits virtual functions from a base class, it is
not an aggregtae.

llvm-svn: 334763
2018-06-14 20:03:22 +00:00
Eric Fiselier 92e523bf55 [Sema] Use %sub to cleanup overload diagnostics
Summary:
This patch adds the newly added `%sub` diagnostic modifier to cleanup repetition in the overload candidate diagnostics.

I think this should be good to go.

@rsmith: Some of the notes now emit `function template` where they only said `function` previously. It seems OK to me, but I would like your sign off on it.


Reviewers: rsmith, EricWF

Reviewed By: EricWF

Subscribers: cfe-commits, rsmith

Differential Revision: https://reviews.llvm.org/D47101

llvm-svn: 333485
2018-05-30 01:00:41 +00:00
Eric Fiselier fcd50538c2 Adjust and fix failing CXX tests after r332799
llvm-svn: 332800
2018-05-19 03:33:56 +00:00
Richard Smith cbebd6226d Fix regression in r332076.
If the name after 'template' is an unresolved using declaration (not containing
'typename'), then we don't yet know if it's a valid template-name, so don't
reject it prior to instantiation. Instead, treat it as naming a dependent
member of the current instantiation.

llvm-svn: 332291
2018-05-14 20:52:48 +00:00
Richard Smith d699da427a PR37450: Fix bug that disabled some type checks for variables with deduced types.
Also improve diagnostic for the case where a type is non-literal because it's a lambda.

llvm-svn: 332286
2018-05-14 20:15:04 +00:00
Richard Smith 7981004eb7 Improve diagnostics and error recovery for template name lookup.
For 'x::template y', consistently give a "no member named 'y' in 'x'"
diagnostic if there is no such member, and give a 'template keyword not
followed by a template' name error if there is such a member but it's not a
template. In the latter case, add a note pointing at the non-template.

Don't suggest inserting a 'template' keyword in 'X::Y<' if X is dependent
if the lookup of X::Y was actually not a dependent lookup and found only
non-templates.

llvm-svn: 332076
2018-05-11 02:43:08 +00:00
Lei Liu 413f3c5595 [Sema] Do not match function type with const T in template argument deduction
From http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1584,
function type should not match cv-qualified type in template argument
deduction. This also matches what GCC and EDG do in template argument
deduction.

Differential Revision: https://reviews.llvm.org/D45755

llvm-svn: 331424
2018-05-03 01:43:23 +00:00
Richard Smith c08b693e30 Parse A::template B as an identifier rather than as a template-id with no
template arguments.

This fixes some cases where we'd incorrectly accept "A::template B" when B is a
kind of template that requires template arguments (in particular, a variable
template or a concept).

llvm-svn: 331013
2018-04-27 02:00:13 +00:00
Richard Smith 213aee0bdd DR727: remove wrong assertion for use of class-scope explicit
specialization without -fms-extensions.

llvm-svn: 330626
2018-04-23 18:38:30 +00:00
Aaron Ballman fbedb97dd2 Allow [[maybe_unused]] on static data members; these are considered variables and the attribute should appertain to them.
Patch by S. B. Tam.

llvm-svn: 329904
2018-04-12 12:21:41 +00:00
Alexander Kornienko 2a8c18d991 Fix typos in clang
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:

  archtype
  cas
  classs
  checkk
  compres
  definit
  frome
  iff
  inteval
  ith
  lod
  methode
  nd
  optin
  ot
  pres
  statics
  te
  thru

Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)

Differential revision: https://reviews.llvm.org/D44188

llvm-svn: 329399
2018-04-06 15:14:32 +00:00
Richard Smith c9c3a004ae Add a couple more tests for DR372.
llvm-svn: 329352
2018-04-05 21:49:20 +00:00
Richard Smith b6070db0d0 DR1672, DR1813, DR1881, DR2120: Implement recent fixes to "standard
layout" rules.

The new rules say that a standard-layout struct has its first non-static
data member and all base classes at offset 0, and consider a class to
not be standard-layout if that would result in multiple subobjects of a
single type having the same address.

We track "is C++11 standard-layout class" separately from "is
standard-layout class" so that the ABIs that need this information can
still use it.

Differential Revision: https://reviews.llvm.org/D45176

llvm-svn: 329332
2018-04-05 18:55:37 +00:00
Zhihao Yuan 2c5471ddc7 [C++17] Fix class template argument deduction for default constructors without an initializer
Summary:
As the title says, this makes following code compile:

```
template<typename> struct Foo {};
Foo() -> Foo<void>;

Foo f; // ok
```

Thanks Nicolas Lesser for coining the fix.

Reviewers: rsmith, lichray

Reviewed By: rsmith, lichray

Subscribers: lichray, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D38216

llvm-svn: 328409
2018-03-24 04:32:11 +00:00
Zhihao Yuan 52b5bf8ba9 [C++17] Allow an empty expression in an if init statement
Summary:
This fixes [PR35381](https://llvm.org/pr35381) and an additional bug where clang didn't warn about the C++17 extension when having an expression in the init statement.

Thanks Nicolas Lesser for contributing the patch.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: erik.pilkington, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D40445

llvm-svn: 327782
2018-03-17 21:42:10 +00:00
Aaron Ballman 33e90d160b Implement DR2229, which prohibits unnamed bit-fields from having qualifiers in C++.
llvm-svn: 327781
2018-03-17 21:08:40 +00:00
Richard Smith c660c8f5d2 Implement C++ DR727, which permits explicit specializations at class scope.
More generally, this permits a template to be specialized in any scope in which
it could be defined, so this also supersedes DR44 and DR374 (the latter of
which we previously only implemented in C++11 mode onwards due to unclarity as
to whether it was a DR).

llvm-svn: 327705
2018-03-16 13:36:56 +00:00
Richard Smith 5d3310208a When substituting previously-checked template arguments into a template
template parameter that is an expanded parameter pack, only substitute into the
current slice, not the entire pack.

This reduces the checking of N template template arguments for an expanded
parameter pack containing N parameters from quadratic time to linear time in
the length of the pack. This is important because one (and possibly the only?)
general technique for splitting a template parameter pack in linear time
depends on doing this.

llvm-svn: 326973
2018-03-08 01:07:33 +00:00
Mikhail Maltsev 2373516cad [Sema] Improve test coverage of narrowing conversion diagnostics
Summary:
This patch adds tests of narrowing conversion diagnostics for the
'unscoped enum -> integer' case.

Reviewers: faisalv, rsmith, rogfer01

Reviewed By: rogfer01

Subscribers: cfe-commits, rogfer01

Differential Revision: https://reviews.llvm.org/D43572

llvm-svn: 326551
2018-03-02 10:03:02 +00:00
Richard Smith 77a9c60aa6 Fix a couple of cases where we would fail to correctly parse deduced class template specialization types.
Specifically, we would not properly parse these types within template arguments
(for non-type template parameters), and in tentative parses. Fixing both of
these essentially requires that we parse deduced template specialization types
as types in all contexts, even in template argument lists -- in particular,
tentative parsing may look ahead and annotate a deduced template specialization
type before we figure out that we're actually supposed to treat the tokens as a
template-name. We deal with this by simply permitting deduced template
specialization types when parsing template arguments, and converting them to
template template arguments.

llvm-svn: 326299
2018-02-28 03:02:23 +00:00
Rafael Espindola 922f2aa9b2 Bring r325915 back.
The tests that failed on a windows host have been fixed.

Original message:

Start setting dso_local for COFF.

With this there are still some GVs where we don't set dso_local
because setGVProperties is never called. I intend to fix that in
followup commits. This is just the bare minimum to teach
shouldAssumeDSOLocal what it should do for COFF.

llvm-svn: 325940
2018-02-23 19:30:48 +00:00
Mikhail Maltsev 7b1a950c4a [Sema] Classify conversions from enum to float as narrowing
Summary:
According to [dcl.init.list]p7:
  A narrowing conversion is an implicit conversion
  - ...
  - from an integer type or unscoped enumeration type to a
    floating-point type, except where the source is a constant
    expression and the actual value after conversion will fit into
    the target type and will produce the original value when
    converted back to the original type, or
  - ...

Currently clang does not handle the 'unscoped enumeration' case. This
patch fixes the corresponding check.

Reviewers: faisalv, rsmith, rogfer01

Reviewed By: rogfer01

Subscribers: rogfer01, cfe-commits

Differential Revision: https://reviews.llvm.org/D42545

llvm-svn: 325668
2018-02-21 10:08:18 +00:00
Richard Smith 2e8a8629d6 Fix test failure on target where size_t is long long.
llvm-svn: 325540
2018-02-19 22:50:50 +00:00
Richard Smith 90c47cad22 [cxx_dr_status] Tests for CWG issues 641-687.
llvm-svn: 325475
2018-02-19 09:05:48 +00:00
Mikhail Maltsev 8d9acc5342 [Sema] Fix decltype of static data members
Summary:
According to the C++11 standard [dcl.type.simple]p4:
  The type denoted by decltype(e) is defined as follows:
  - if e is an unparenthesized id-expression or an unparenthesized
    class member access (5.2.5), decltype(e) is the type of the entity
    named by e.
    
Currently Clang handles the 'member access' case incorrectly for
static data members (decltype returns T& instead of T). This patch
fixes the issue.

Reviewers: faisalv, rsmith, rogfer01

Reviewed By: rogfer01

Subscribers: rogfer01, cfe-commits

Differential Revision: https://reviews.llvm.org/D42969

llvm-svn: 325117
2018-02-14 11:34:25 +00:00
Jan Korous 3a98e51823 [Parser][FixIt] Better diagnostics for "typedef" instead of "typename" typo
rdar://problem/10214588

Differential Revision: https://reviews.llvm.org/D42170

llvm-svn: 324607
2018-02-08 14:37:58 +00:00
Richard Smith 56ae0a67e8 DR126: partially implement the const-correct rules for exception handler matching.
While here, fix up the myriad other ways in which Sema's two "can this handler
catch that exception?" implementations get things wrong and unify them.

llvm-svn: 322431
2018-01-13 05:05:45 +00:00
Richard Smith 9fb4e60d7d PR33503: When a qualified name in a redeclaration names a prior declaration in
an inline namespace, update its semantic DeclContext to match.

We would previously get the semantic DeclContext wrong (pointing to the named
scope rather than the inline namespace within it), resulting in wrong lookup
results and linkage-related problems if the inline namespace was an anonymous
namespace.

llvm-svn: 321770
2018-01-03 23:03:54 +00:00