Other compilers accept invalid code here that we reject, and we need a
better error message to try to convince users that the code is really
incorrect. Consider:
class Foo {
typedef MyIterHelper<Foo> iterator;
friend class iterator;
};
Previously our wording was "elaborated type refers to a typedef".
"elaborated type" isn't widely known terminology, so the new diagnostic
says "typedef 'iterator' cannot be referenced with class specifier".
Reviewers: rsmith
Differential Revision: https://reviews.llvm.org/D25216
llvm-svn: 289259
Some functions and templates are treated as __host__ __device__ even
when they don't have explicitly specified target attributes.
What's worse, this treatment may change depending on command line
options (-fno-cuda-host-device-constexpr) or
#pragma clang force_cuda_host_device.
Combined with strict checking for matching function target that comes
with D25809(r288962), it makes it hard to write code which would
explicitly instantiate or specialize some functions regardless of
pragmas or command line options in effect.
This patch changes the way we match target attributes of base template
vs attributes used in explicit instantiation or specialization so that
only explicitly specified attributes are considered. This makes base
template selection behave consistently regardless of pragma of command
line options that may affect CUDA target.
Differential Revision: https://reviews.llvm.org/D25845
llvm-svn: 289091
* __host__ __device__ functions are no longer considered to be
redeclarations of __host__ or __device__ functions. This prevents
unintentional merging of target attributes across them.
* Function target attributes are not considered (and must match) during
explicit instantiation and specialization of function templates.
Differential Revision: https://reviews.llvm.org/D25809
llvm-svn: 288962
On MSVC, if an implicit instantiation already exists and an explicit
instantiation definition with a DLL attribute is created, the DLL
attribute still takes effect. Make clang match this behavior for
exporting.
Differential Revision: https://reviews.llvm.org/D26657
llvm-svn: 288682
An explicit template specialization can cause the implicit template
specialization of a type which inherits the attributes. In such a case, we
would end up with a delayed template specialization for a dll exported type
which we would fail to reference. This would trigger an assertion.
We now propagate the dll storage attributes through the inheritance
chain. Only after having done so do we reference the delayed template
specializations. This allows any implicit specializations which inherit dll
storage to also be referenced.
llvm-svn: 288570
arguments from a declaration; despite what the standard says, this form of
deduction should not be considering exception specifications.
llvm-svn: 288301
Similar to r284288, make the Itanium ABI follow MS ABI dllexport
semantics in the case of an explicit instantiation declaration followed
by a dllexport explicit instantiation definition.
Differential Revision: https://reviews.llvm.org/D26471
llvm-svn: 286419
This commit improves the "must have C++ linkage" error diagnostics that are
emitted for C++ declarations like templates and literal operators by adding an
additional note that points to the appropriate extern "C" linkage specifier.
rdar://19021120
Differential Revision: https://reviews.llvm.org/D26189
llvm-svn: 285823
1) Merge and demote variable definitions when we find a redefinition in
MergeVarDecls, not only when we find one in AddInitializerToDecl (we only reach
the second case if it's the addition of the initializer itself that converts an
existing declaration into a definition).
2) When rebuilding a redeclaration chain for a variable, if we merge two
definitions together, mark the definitions as merged so the retained definition
is made visible whenever the demoted definition would have been.
Original commit message (from r283882):
[modules] PR28752: Do not instantiate variable declarations which are not visible.
Original patch by Vassil Vassilev! Changes listed above are mine.
llvm-svn: 284284
Original message:
"[modules] PR28752: Do not instantiate variable declarations which are not visible.
https://reviews.llvm.org/D24508
Patch developed in collaboration with Richard Smith!"
llvm-svn: 284008
Summary:
This is possible now that MapVector supports move-only values.
Depends on D25404.
Reviewers: timshen
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25405
llvm-svn: 283766
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
within the instantiation of that same specialization. This could previously
happen for eagerly-instantiated function templates, variable templates,
exception specifications, default arguments, and a handful of other cases.
We still have an issue here for default template arguments that recursively
make use of themselves and likewise for substitution into the type of a
non-type template parameter, but in those cases we're producing a different
entity each time, so they should instead be caught by the instantiation depth
limit. However, currently we will typically run out of stack before we reach
it. :(
llvm-svn: 280190
to DiagnoseUninstantiableTemplate, teach hasVisibleDefinition to correctly
determine whether a function definition is visible, and mark both the function
and the template as visible when merging function template definitions to
provide hasVisibleDefinition with the relevant information.
The change to always pass the right declaration as the PatternDef to
DiagnoseUninstantiableTemplate also caused those checks to happen before other
diagnostics in InstantiateFunctionDefinition, giving worse diagnostics for the
same situations, so I sunk the relevant diagnostics into
DiagnoseUninstantiableTemplate. Those parts of this patch are based on changes
in reviews.llvm.org/D23492 by Vassil Vassilev.
This reinstates r279486, reverted in r279500, with a fix to
DiagnoseUninstantiableTemplate to only mark uninstantiable explicit
instantiation declarations as invalid if we actually diagnosed them. (When we
trigger an explicit instantiation of a class member from an explicit
instantiation declaration for the class, it's OK if there is no corresponding
definition and we certainly don't want to mark the member invalid in that
case.) This previously caused a build failure during bootstrap.
llvm-svn: 279557
to DiagnoseUninstantiableTemplate, teach hasVisibleDefinition to correctly
determine whether a function definition is visible, and mark both the function
and the template as visible when merging function template definitions to
provide hasVisibleDefinition with the relevant information.
The change to always pass the right declaration as the PatternDef to
DiagnoseUninstantiableTemplate also caused those checks to happen before other
diagnostics in InstantiateFunctionDefinition, giving worse diagnostics for the
same situations, so I sunk the relevant diagnostics into
DiagnoseUninstantiableTemplate. Those parts of this patch are based on changes
in reviews.llvm.org/D23492 by Vassil Vassilev.
llvm-svn: 279486
Summary:
Space for storing the //constraint-expression// of the
//requires-clause// associated with a `TemplateParameterList` is
arranged by taking a bit out of the `NumParams` field for the purpose
of determining whether there is a //requires-clause// or not, and by
adding to the trailing objects tied to the `TemplateParameterList`. An
accessor is provided.
An appropriate argument is supplied to `TemplateParameterList::Create`
at the various call sites.
Serialization changes will addressed as the Concepts implementation
becomes more solid.
Drive-by fix:
This change also replaces the custom
`FixedSizeTemplateParameterListStorage` implementation with one that
follows the interface provided by `llvm::TrailingObjects`.
Reviewers: aaron.ballman, faisalv, rsmith
Subscribers: cfe-commits, nwilson
Differential Revision: https://reviews.llvm.org/D19322
llvm-svn: 276069
After thinking about it, we don't really need to forbid
BuiltinTemplateDecls explicitly. The restriction doesn't really buy us
anything.
llvm-svn: 275078
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
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
Crash reported in PR28023 is caused by the fact that non-type template
parameters are found by tag name lookup. In the code provided in that PR:
template<int V> struct A {
struct B {
template <int> friend struct V;
};
};
the template parameter V is found when lookup for redeclarations of 'struct V'
is made. Latter on the error about shadowing of 'V' is emitted but the semantic
context of 'struct V' is already determined wrong: 'struct A' instead of
translation unit.
The fix moves the check for shadowing toward the beginning of the method and
thus prevents from wrong context calculations.
This change fixes PR28023.
llvm-svn: 272366
Also make explicit instantiation decls not apply to nested classes when
targeting MSVC. That dll attributes are not inherited by inner classes
might be the explanation for MSVC's behaviour here.
llvm-svn: 270897
This matches what MSVC does, and should make compiles faster by avoiding to
unnecessarily emit a lot of code.
Differential Revision: http://reviews.llvm.org/D20608
llvm-svn: 270748
This is in preparation for C++ P0136R1, which switches the model for inheriting
constructors over from synthesizing a constructor to finding base class
constructors (via using shadow decls) when looking for derived class
constructors.
llvm-svn: 269231
declared before it is used. Because we don't use normal name lookup to find
these, the normal code to filter out non-visible names from name lookup results
does not apply.
llvm-svn: 268585
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
Summary: A program shall not declare an explicit instantiation (14.8.2), an explicit specialization (14.8.3), or a partial specialization of a concept definition.
Reviewers: rsmith, hubert.reinterpretcast, faisalv, aaron.ballman
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D18221
llvm-svn: 265868
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
The prior diagnostic (err_template_arg_not_class_template) would state that the template argument to a template template parameter can only be a class template, when it can also be a template alias. The newly renamed diagnostic (err_template_arg_not_valid_template) mentions template aliases.
llvm-svn: 264522
This feature works outside of templates by forming a DeclRefExpr to a
FieldDecl instead of a MemberExpr, which requires a base object in
addition to the FieldDecl.
Previously, while building up the template AST before instantiation, we
formed a CXXDependentScopeMemberExpr, which always instantiates to a
MemberExpr. Now, in unevaluated contexts we form a
DependentScopeDeclRefExpr, which is a more flexible node that can
instantiate to either a MemberExpr or a DeclRefExpr depending on lookup
results.
Fixes PR26893.
llvm-svn: 263279
Relands r260194 with a fix. If we have a template that transitions from
an extern template to an explicitly instantiated dllexport template, we
would add that class to the delayed exported class list without flushing
it.
For explicit instantiations, we can just flush the list of delayed
classes immediately. We don't have to worry about the bug fixed in
r260194 in this case because explicit instantiations can only occur at
file and namespace scope.
Fixes PR26490.
llvm-svn: 262056
Reid Kleckner