From http://reviews.llvm.org/D4368 these cases were thought to not be reachable
and the checks removed before the rest of the code was committed in r216649.
However, these cases are reachable and the checks are added back.
llvm-svn: 317957
Given a choice between a constructor call and a conversion function in C++17,
we prefer the constructor for direct-initialization and the conversion function
for copy-initialization, matching the behavior in C++14 and before. The
guaranteed copy elision rules were not intended to change the meaning of such
code (other than by removing unnecessary copy constructor calls).
This tweak will be raised with CWG.
llvm-svn: 317066
Summary:
Clang typically warns that in the following class hierarchy, 'A' is
inaccessible because there is no series of casts that the user can
write to access it unambiguously:
struct A { };
struct B : A { };
struct C : A, B { };
MSVC allows the user to convert from C* to A*, though, and we've
encountered this issue in the latest Windows SDK headers.
This patch allows this conversion when -fms-compatibility is set and
adds a warning for it under -Wmicrosoft-inaccessible-base.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D39389
llvm-svn: 316807
Summary:
The warning was initially introduced in D32914 by @thakis,
and the concerns were raised there, and later in rL302247
and PR33771.
I do believe that it makes sense to relax the diagnostic
e.g. in this case, when the expression originates from the
system header, which can not be modified. This prevents
adoption for the diagnostic for codebases which use pthreads
(`PTHREAD_MUTEX_INITIALIZER`), gtest, etc.
As @malcolm.parsons suggests, it *may* make sense to also
not warn for the template types, but it is not obvious to
me how to do that in here.
Though, it still makes sense to complain about `NULL` macro.
While there, add more tests.
Reviewers: dblaikie, thakis, rsmith, rjmccall, aaron.ballman
Reviewed By: thakis
Subscribers: Rakete1111, hans, cfe-commits, thakis, malcolm.parsons
Tags: #clang
Differential Revision: https://reviews.llvm.org/D38954
llvm-svn: 316662
C++14 [dcl.constexpr]p4 states that in the body of a constexpr
constructor,
> every non-variant non-static data member and base class sub-object
shall be initialized
However, [class.bit]p2 notes that
> Unnamed bit-fields are not members and cannot be initialized.
Therefore, we should make sure to filter them out of the check that
all fields are initialized.
Fixing this makes the constant evaluator a bit smarter, and
specifically allows constexpr constructors to avoid tripping
-Wglobal-constructors when the type contains unnamed bitfields.
Reviewed at https://reviews.llvm.org/D39035.
llvm-svn: 316408
Allow Obj-C ivars with incomplete array type but only as the last ivar.
Also add a requirement for ivars that contain a flexible array member to
be at the end of class too. It is possible to add in a subclass another
ivar at the end but we'll emit a warning in this case. Also we'll emit a
warning if a variable sized ivar is declared in class extension or in
implementation because subclasses won't know they should avoid adding
new ivars.
In ARC incomplete array objects are treated as __unsafe_unretained so
require them to be marked as such.
Prohibit synthesizing ivars with flexible array members because order of
synthesized ivars is not obvious and tricky to control. Spelling out
ivar explicitly gives control to developers and helps to avoid surprises
with unexpected ivar ordering.
For C and C++ changed diagnostic to tell explicitly a field is not the
last one and point to the next field. It is not as useful as in Obj-C
but it is an improvement and it is consistent with Obj-C. For C for
unions emit more specific err_flexible_array_union instead of generic
err_field_incomplete.
rdar://problem/21054495
Reviewers: rjmccall, theraven
Reviewed By: rjmccall
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D38773
llvm-svn: 316381
constant expressions.
We permit array-to-pointer decay on such arrays, but disallow pointer
arithmetic (since we do not know whether it will have defined behavior).
This is based on r311970 and r301822 (the former by me and the latter by Robert
Haberlach). Between then and now, two things have changed: we have committee
feedback indicating that this is indeed the right direction, and the code
broken by this change has been fixed.
This is necessary in C++17 to continue accepting certain forms of non-type
template argument involving arrays of unknown bound.
llvm-svn: 316245
If the variable construction can be constant evaluated it doesn't have
side effects, so removing it is always safe. We only try to evaluate
variables that are unused, there should be no impact on compile time.
Differential Revision: https://reviews.llvm.org/D38678
llvm-svn: 315787
This feature is not (yet) approved by the C++ committee, so this is liable to
be reverted or significantly modified based on committee feedback.
No functionality change intended for existing code (a new type must be defined
in namespace std to take advantage of this feature).
llvm-svn: 315662
When declaring an entity in the "purview" of a module, it's never a
redeclaration of an entity in the purview of a default module or in no module
("in the global module"). Don't consider those other declarations as possible
redeclaration targets if they're not visible, and reject any cases where we
pick a prior visible declaration that violates this rule.
This reinstates r315251 and r315256, reverted in r315309 and r315308
respectively, tweaked to avoid triggering a linkage calculation when declaring
implicit special members (this exposed our pre-existing issue with typedef
names for linkage changing the linkage of types whose linkage has already been
computed and cached in more cases). A testcase for that regression has been
added in r315366.
llvm-svn: 315379
When declaring an entity in the "purview" of a module, it's never a
redeclaration of an entity in the purview of a default module or in no module
("in the global module"). Don't consider those other declarations as possible
redeclaration targets if they're not visible, and reject any cases where we
pick a prior visible declaration that violates this rule.
llvm-svn: 315251
Move the logic for determining the `wchar_t` type information into the
driver. Rather than passing the single bit of information of
`-fshort-wchar` indicate to the frontend the desired type of `wchar_t`
through a new `-cc1` option of `-fwchar-type` and indicate the
signedness through `-f{,no-}signed-wchar`. This replicates the current
logic which was spread throughout Basic into the
`RenderCharacterOptions`.
Most of the changes to the tests are to ensure that the frontend uses
the correct type. Add a new test set under `test/Driver/wchar_t.c` to
ensure that we calculate the proper types for the various cases.
llvm-svn: 315126
If we resolve an overloaded operator call to a specific function during
template definition, don't perform ADL during template instantiation.
Doing so finds overloads that we're not supposed to find.
llvm-svn: 315005
Summary:
Fix an assertion failure (http://llvm.org/PR34800) and clean up unused code relevant to the fixed logic.
A bit of context: when `SExprBuilder::translateMemberExpr` is called on a member expression that involves a conversion operator, for example, `til::Project` constructor can't just call `getName()` on it, since the name is not a simple identifier. In order to handle this case I've introduced an optional string to print the member name to. I discovered that the other two `til::Project` constructors are not used, so it was better to delete them instead of ensuring they work correctly with the new logic.
Reviewers: aaron.ballman
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D38458
llvm-svn: 314895
In C++, such initialization of std::array<T, N> types is guaranteed to work by
the standard, is completely idiomatic, and the "suggested" alternative from
Clang was technically invalid.
llvm-svn: 314838
This reverts r314461.
It is warning on user code that uses END_COM_MAP(), which expands to
declare QueryInterface with conflicting exception specifers. I've spent
a while trying to understand why, but haven't been able to extract a
reduced test case. Let's revert and I'll keep trying.
llvm-svn: 314689
This expects the warning;
File clang/test/SemaCXX/ms-iunknown-template-function.cpp Line 19: __declspec attribute 'novtable' is not supported
But for targeting *-win32, the warning is not seen.
error: 'warning' diagnostics expected but not seen:
File clang\test\SemaCXX\ms-iunknown-template-function.cpp Line 19 (directive at clang\test\SemaCXX\ms-iunknown-template-function.cpp:18): __declspec attribute 'novtable'
llvm-svn: 314586
function-style cast.
This fires for cases such as
T(x);
... where 'x' was previously declared and T is a type. This construct declares
a variable named 'x' rather than the (probably expected) interpretation of a
function-style cast of 'x' to T.
llvm-svn: 314570
Apparently, the MSVC SDK has a strange implementation that
causes a number of implicit functions as well as a template member
function of the IUnknown type. This patch allows these as InterfaceLike
types as well.
Additionally, it corrects the behavior where extern-C++ wrapped around an
Interface-Like type would permit an interface-like type to exist in a namespace.
Differential Revision: https://reviews.llvm.org/D38303
llvm-svn: 314557
As reported in https://bugs.llvm.org/show_bug.cgi?id=33235,
a noexcept function was unable to inherit from a nothrow defaulted
constructor. Attribute "nothrow" is supposed to be semantically
identical to noexcept, and in fact, a number of other places in the
code treat them identically.
This patch simply checks the RecordDecl for the correct attribute in
the case where no other exception specifier was set.
Differential Revision: https://reviews.llvm.org/D38209
llvm-svn: 314462
I discovered it was possible to create a 'nothrow' noexcept(false)
function, which is both non-sensical as well as seemingly breaking.
This patch warns if attribute nothrow is used with anything besides "noexcept".
"noexcept(true)" isn't possible, because the noexcept decl isn't parsed until
later.
Differential Revision: https://reviews.llvm.org/D38205
llvm-svn: 314461
It was brought up in response to my last implementation for
this struct-as-interface features that at least 1 header in
the MS SDK uses "extern C++" around an IUnknown declaration.
The previous implementation demanded that this type exist
in the TranslationUnit DeclContext. This small change simply
also allows in the situation where we're extern "C++".
llvm-svn: 314235
When selecting constructors for initializing an object of type T from a single
expression of class type U, also consider conversion functions of U that
convert to T (rather than modeling such conversions as calling a conversion
function and then calling a constructor).
This approach is proposed as the resolution for the defect, and is also already
implemented by GCC.
llvm-svn: 314231
Discovered that 'nothrow' (which is supposed to be an alias for noexcept)
was not warning with a throw inside of it. This patch corrects the behavior
previously created to add 'nothrow' to this list.
Differential Revision: https://reviews.llvm.org/D38203
llvm-svn: 314229
The `__va_start` intrinsic for Windows ARM does not account for const
correctness when performing a check. All local qualifiers are ignored
when validating the invocation. This was exposed by building the swift
stdlib against the Windows 10586 SDK for ARM. Simply expand out the
check for the two parameters and ignore the qualifiers for the check.
llvm-svn: 314226
This doesn't affect our code generation in any material way -- we already give
such declarations internal linkage from a codegen perspective -- but it has
some subtle effects on code validity.
We suppress the 'L' (internal linkage) marker for mangled names in anonymous
namespaces, because it is redundant (the information is already carried by the
namespace); this deviates from GCC's behavior if a variable or function in an
anonymous namespace is redundantly declared 'static' (where GCC does include
the 'L'), but GCC's behavior is incoherent because such a declaration can be
validly declared with or without the 'static'.
We still deviate from the standard in one regard here: extern "C" declarations
in anonymous namespaces are still granted external linkage. Changing those does
not appear to have been an intentional consequence of the standard change in
DR1113.
llvm-svn: 314037
This implements the proposed approach in https://github.com/itanium-cxx-abi/cxx-abi/issues/33
This reinstates r313827, reverted in r313856, with a fix for the 'out-of-bounds
enumeration value' ubsan error in that change.
llvm-svn: 313955
Richard Trieu