According to [dcl.type.elab] p4:
> If an _elaborated-type-specifier_ appears with the `friend` specifier
as an entire _member-declaration_, the _member-declaration_ shall have
one of the following forms:
> `friend` _class-key_ _nested-name-specifier_(opt) _identifier_ `;`
> `friend` _class-key_ _simple-template-id_ `;`
> `friend` _class-key_ _nested-name-specifier_ `template`(opt)
_simple-template-id_ `;`
Notably absent from this list is the `enum` form of an
_elaborated-type-specifier_ "`enum` _nested-name-specifier_(opt)
_identifier_", which appears to be intentional per the resolution of
CWG2363.
Most major implementations accept these declarations, so the diagnostic
is a pedantic warning across all C++ versions.
In addition to the trivial cases previously diagnosed in C++98, we now
diagnose cases where the _elaborated-type-specifier_ has a dependent
_nested-name-specifier_:
```
template<typename T>
struct A
{
enum class E;
};
struct B
{
template<typename T>
friend enum A<T>::E; // pedantic warning: elaborated enumeration type cannot be a friend
};
template<typename T>
struct C
{
friend enum T::E; // pedantic warning: elaborated enumeration type cannot be a friend
};
```
We have a new policy in place making links to private resources
something we try to avoid in source and test files. Normally, we'd
organically switch to the new policy rather than make a sweeping change
across a project. However, Clang is in a somewhat special circumstance
currently: recently, I've had several new contributors run into rdar
links around test code which their patch was changing the behavior of.
This turns out to be a surprisingly bad experience, especially for
newer folks, for a handful of reasons: not understanding what the link
is and feeling intimidated by it, wondering whether their changes are
actually breaking something important to a downstream in some way,
having to hunt down strangers not involved with the patch to impose on
them for help, accidental pressure from asking for potentially private
IP to be made public, etc. Because folks run into these links entirely
by chance (through fixing bugs or working on new features), there's not
really a set of problematic links to focus on -- all of the links have
basically the same potential for causing these problems. As a result,
this is an omnibus patch to remove all such links.
This was not a mechanical change; it was done by manually searching for
rdar, radar, radr, and other variants to find all the various
problematic links. From there, I tried to retain or reword the
surrounding comments so that we would lose as little context as
possible. However, because most links were just a plain link with no
supporting context, the majority of the changes are simple removals.
Differential Review: https://reviews.llvm.org/D158071
C89 allowed a type specifier to be elided with the resulting type being
int, aka implicit int behavior. This feature was subsequently removed
in C99 without a deprecation period, so implementations continued to
support the feature. Now, as with implicit function declarations, is a
good time to reevaluate the need for this support.
This patch allows -Wimplicit-int to issue warnings in C89 mode (off by
default), defaults the warning to an error in C99 through C17, and
disables support for the feature entirely in C2x. It also removes a
warning about missing declaration specifiers that really was just an
implicit int warning in disguise and other minor related cleanups.
scope.
There are a few contexts in which we assume a name is a template name;
if such a context is one where we should perform an unqualified lookup,
and lookup finds nothing, we would form a dependent template name even
if the name is not dependent. This happens in particular for the lookup
of a pseudo-destructor.
In passing, rename ActOnDependentTemplateName to just ActOnTemplateName
given that we apply it for non-dependent template names too.
Also add extension warnings for the cases that are disallowed by the
current rules for destructor name lookup, refactor and simplify the
lookup code, and improve the diagnostic quality when lookup fails.
The special case we previously supported for converting
p->N::S<int>::~S() from naming a class template into naming a
specialization thereof is subsumed by a more general rule here (which is
also consistent with Clang's historical behavior and that of other
compilers): if we can't find a suitable S in N, also look in N::S<int>.
The extension warnings are off by default, except for a warning when
lookup for p->N::S::~T() looks for T in scope instead of in N (or N::S).
That seems sufficiently heinous to warn on by default, especially since
we can't support it for a dependent nested-name-specifier.
A TemplateIdAnnotation represents only a template-id, not a
nested-name-specifier plus a template-id. Don't make a redundant copy of
the CXXScopeSpec and store it on the template-id annotation.
This slightly improves error recovery by more properly handling the case
where we would form an invalid CXXScopeSpec while parsing a typename
specifier, instead of accidentally putting the token stream into a
broken "annot_template_id with a scope specifier, but with no preceding
annot_cxxscope token" state.
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
In `ParseDeclarationSpecifiers` for the code
class A typename A;
we were able to annotate token `kw_typename` because it refers to
existing type. But later during processing token `annot_typename` we
failed to `SetTypeSpecType` and exited switch statement leaving
annotation token unconsumed. The code after the switch statement failed
because it didn't expect a special token.
The fix is not to assume that switch statement consumes all special
tokens and consume any token, not just non-special.
rdar://problem/37099386
Reviewers: rsmith, arphaman
Reviewed By: rsmith
Subscribers: jkorous-apple, cfe-commits
Differential Revision: https://reviews.llvm.org/D44449
llvm-svn: 329735
Suggest moving the following erroneous attrib list (based on location)
[[]] struct X;
to
struct [[]] X;
Additionally, added a fixme for the current implementation that diagnoses misplaced attributes to consider using the newly introduced diagnostic (that I think is more user-friendly).
llvm-svn: 321449
This is a slightly odd construct (it's more common to see "A (::B)()") but can
happen in friend declarations, and the parens are not redundant as they prevent
the :: binding to the left.
llvm-svn: 321318
and we see an ill-formed declarator that would probably be well-formed if the
tag definition were just missing a semicolon, use that as the diagnostic
instead of producing some other mysterious error.
llvm-svn: 195163
that looks like a function declaration, except that it's missing a return type,
try typo-correcting it to the relevant constructor name.
In passing, fix a bug where the missing-type-specifier recovery codepath would
drop a preceding scope specifier on the floor, leading to follow-on diagnostics
and incorrect recovery for the auto-in-c++98 hack.
llvm-svn: 192644
Summary:
Parsing cast expressions during error recovery can put us in a bad
state. Check to see if the token for a simple-type-specifier makes
sense before further parsing.
Fixes PR17255.
Reviewers: rsmith, doug.gregor, CornedBee, eli.friedman
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1696
llvm-svn: 191159
is at the end of the line, point to the location after the double colon instead
of at the next token. There is more context to be given this way. In addition,
the next token can be several lines later.
llvm-svn: 190029
followed by an identifier, then diagnose an identifier as being a bogus part of
the declarator instead of tripping over it. Improves diagnostics for cases like
std::vector<const int *p> my_vec;
llvm-svn: 186061
It turns out that there's no correctness bug here (because we can't have a type
definition in this location), but there was a diagnostic bug.
llvm-svn: 173766
on a type. Currently, it gives a generic "expected unqualified-id" error.
The new error message is "cannot use (dot|arrow) operator on a type".
llvm-svn: 173556
r159549 / r159164 regressed clang to reject
struct s {};
struct s
operator++(struct s a)
{ return a; }
This fixes the regression. Richard, pleas check if this looks right.
llvm-svn: 172834
nested names as id-expressions, using the annot_primary_expr annotation, where
possible. This removes some redundant lookups, and also allows us to
typo-correct within tentative parsing, and to carry on disambiguating past an
identifier which we can determine will fail lookup as both a type and as a
non-type, allowing us to disambiguate more declarations (and thus offer
improved error recovery for such cases).
This also introduces to the parser the notion of a tentatively-declared name,
which is an identifier which we *might* have seen a declaration for in a
tentative parse (but only if we end up disambiguating the tokens as a
declaration). This is necessary to correctly disambiguate cases where a
variable is used within its own initializer.
llvm-svn: 162159
scope to -Wc++11-extensions. Move extra semicolon after member function
definition diagnostic out of -pedantic, since C++ allows a single semicolon
there. Keep it in -Wextra-semi, though, since it's still questionable.
llvm-svn: 160618
instead of a semicolon (as sometimes happens during refactorings). When such a
comma is seen at the end of a line, and is followed by something which can't
possibly be a declarator (or even something which might be a plausible typo for
a declarator), suggest that a semicolon was intended.
llvm-svn: 142544
signal an error. This can happen even when the current token is '::' if
this is a ::new or ::delete expression.
This was an oversight in my recent parser refactor; fixes PR 5825.
llvm-svn: 97462
t.cc:4:3: error: expected ';' at end of declaration list
int y;
^
t.cc:6:1: error: expected ';' at end of declaration list
};
^
After:
t.cc:3:8: error: expected ';' at end of declaration list
int x
^
;
t.cc:5:8: error: expected ';' at end of declaration list
int z
^
;
llvm-svn: 95039
- This is designed to make it obvious that %clang_cc1 is a "test variable"
which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
can be useful to redefine what gets run as 'clang -cc1' (for example, to set
a default target).
llvm-svn: 91446
intended. On the first testcase in the bug, we now produce:
cxx-decl.cpp:12:2: error: unexpected ':' in nested name specifier
y:a a2;
^
::
instead of:
t.cc:8:1: error: C++ requires a type specifier for all declarations
x:a a2;
^
t.cc:8:2: error: invalid token after top level declarator
x:a a2;
^
;
t.cc:9:11: error: use of undeclared identifier 'a2'
x::a a3 = a2;
^
llvm-svn: 90713
that I noticed working on other things.
Instead of emitting:
t2.cc:1:8: error: use of undeclared identifier 'g'
int x(*g);
^
t2.cc:1:10: error: expected ')'
int x(*g);
^
t2.cc:1:6: note: to match this '('
int x(*g);
^
We now only emit:
t2.cc:1:7: warning: type specifier missing, defaults to 'int'
int x(*g);
^
Note that the example in SemaCXX/nested-name-spec.cpp:f4 is still
not great, we now produce both of:
void f4(undef::C); // expected-error {{use of undeclared identifier 'undef'}} \
expected-error {{variable has incomplete type 'void'}}
The second diagnostic should be silenced by something getting marked invalid.
I don't plan to fix this though.
llvm-svn: 68919
