fatal error. Previously, if a fatal error was followed by a diagnostic which
was suppressed due to a SFINAETrap, we'd forget that we'd seen a fatal error.
llvm-svn: 164437
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
This is effectively a warning for code that violates core issue 903 & thus will
become standard error in the future, hopefully. It catches strange null
pointers such as: '\0', 1 - 1, const int null = 0; etc...
There's currently a flaw in this warning (& the warning for 'false' as a null
pointer literal as well) where it doesn't trigger on comparisons (ptr == '\0'
for example). Fix to come in a future patch.
Also, due to this only being a warning, not an error, it triggers quite
frequently on gtest code which tests expressions for null-pointer-ness in a
SFINAE context (so it wouldn't be a problem if this was an error as in an
actual implementation of core issue 903). To workaround this for now, the
diagnostic does not fire in unevaluated contexts.
Review by Sean Silva and Richard Smith.
llvm-svn: 161501
accurate by asking the parser whether there was an ambiguity rather than trying
to reverse-engineer it from the DeclSpec. Make the with-parameters case have
better diagnostics by using semantic information to drive the warning,
improving the diagnostics and adding a fixit.
Patch by Nikola Smiljanic. Some minor changes by me to suppress diagnostics for
declarations of the form 'T (*x)(...)', which seem to have a very high false
positive rate, and to reduce indentation in 'warnAboutAmbiguousFunction'.
llvm-svn: 160998
a defaulted special member function until the exception specification is needed
(using the same criteria used for the delayed instantiation of exception
specifications for function temploids).
EST_Delayed is now EST_Unevaluated (using 1330's terminology), and, like
EST_Uninstantiated, carries a pointer to the FunctionDecl which will be used to
resolve the exception specification.
This is enabled for all C++ modes: it's a little faster in the case where the
exception specification isn't used, allows our C++11-in-C++98 extensions to
work, and is still correct for C++98, since in that mode the computation of the
exception specification can't fail.
The diagnostics here aren't great (in particular, we should include implicit
evaluation of exception specifications for defaulted special members in the
template instantiation backtraces), but they're not much worse than before.
Our approach to the problem of cycles between in-class initializers and the
exception specification for a defaulted default constructor is modified a
little by this change -- we now reject any odr-use of a defaulted default
constructor if that constructor uses an in-class initializer and the use is in
an in-class initialzer which is declared lexically earlier. This is a closer
approximation to the current draft solution in core issue 1351, but isn't an
exact match (but the current draft wording isn't reasonable, so that's to be
expected).
llvm-svn: 160847
as an array of its base class TemplateArgument. Switch the const
TemplateArgument* parameters of InstantiatingTemplate's constructors to
ArrayRef<TemplateArgument> to prevent this from happening again in the future.
llvm-svn: 160245
being a property of a canonical type to being a property of the fully-sugared
type. This should only make a difference in the case where an alias template
ignores one of its parameters, and that parameter is an unexpanded parameter
pack.
llvm-svn: 160244
to the same signature. Fix a bug in the type printer which would cause this
diagnostic to print wonderful types like 'const const int *'.
llvm-svn: 160161
* When substituting a reference to a non-type template parameter pack where the
corresponding argument is a pack expansion, transform into an expression
which contains an unexpanded parameter pack rather than into an expression
which contains a pack expansion. This causes the SubstNonTypeTemplateParmExpr
to be inside the PackExpansionExpr, rather than outside, so the expression
still looks like a pack expansion and can be deduced.
* Teach MarkUsedTemplateParameters that we can deduce a reference to a template
parameter if it's wrapped in a SubstNonTypeTemplateParmExpr (such nodes are
added during alias template substitution).
llvm-svn: 159922
expression, skip over any SubstNonTypeTemplateParmExprs which alias templates
may have inserted before checking for a DeclRefExpr referring to a non-type
template parameter declaration.
llvm-svn: 159909
-ftemplate-depth limit. There are various ways to get an infinite (or merely
huge) stack of substitutions with no intervening instantiations. This is also
consistent with gcc's behavior.
llvm-svn: 159907
which will appear in the vtable as used, not just those ones which were
declared within the class itself. Fixes an issue reported as comment#3 in
PR12763 -- we sometimes assert in codegen if we try to emit a reference to a
function declaration which we've not marked as referenced. This also matches
gcc's observed behavior.
llvm-svn: 159895
in microsoft mode. Fixes PR12701.
The code for this was already in 2 of the 3 branches of a
conditional and missing in the 3rd branch, so lift it above
the conditional.
llvm-svn: 158842
Moves the bool bail-out down a little in SemaChecking - so now
-Wnull-conversion and -Wliteral-conversion can fire when the target type is
bool.
Also improve the wording/details in the -Wliteral-conversion warning to match
the -Wconstant-conversion.
llvm-svn: 156826
candidate template ignored: substitution failed [with T = int]: no type named 'type' in 'std::enable_if<false, void>'
Instead, just say:
candidate template ignored: disabled by 'enable_if' [with T = int]
... and point at the enable_if condition which (we assume) failed.
This is applied to all cases where the user writes 'typename enable_if<...>::type' (optionally prefixed with a nested name specifier), and 'enable_if<...>' names a complete class type which does not have a member named 'type', and this results in a candidate function being ignored in a SFINAE context. Thus it catches 'std::enable_if', 'std::__1::enable_if', 'boost::enable_if' and 'llvm::enable_if'.
llvm-svn: 156463
overload candidate, and include its message in any subsequent 'candidate not
viable due to substitution failure' note we may produce.
To keep the note small (since the 'overload resolution failed' diagnostics are
often already very verbose), the text of the SFINAE diagnostic is included as
part of the text of the note, and any notes which were attached to it are
discarded.
There happened to be spare space in OverloadCandidate into which a
PartialDiagnosticAt could be squeezed, and this patch goes to lengths to avoid
unnecessary PartialDiagnostic copies, resulting in no slowdown that I could
measure. (Removal in passing of some PartialDiagnostic copies has resulted in a
slightly smaller clang binary overall.) Even on a torture test, I was unable to
measure a memory increase of above 0.2%.
llvm-svn: 156297
pretend there was no previous declaration -- that can lead us to injecting
a class template (with no access specifier) into a class scope. Instead,
just avoid the problematic checks.
llvm-svn: 155303
up an elaborated type specifier in a friend declaration, only look for type
declarations, per [basic.lookup.elab]p2. If we know that the redeclaration
lookup for a friend class template in a dependent context finds a non-template,
don't delay the diagnostic to instantiation time.
llvm-svn: 155187
specifications on member function templates of class templates and other such
nested beasties. Store the function template from which we are to instantiate
an exception specification rather than trying to deduce it. Plus some
additional test cases.
llvm-svn: 155076
We have a new flavor of exception specification, EST_Uninstantiated. A function
type with this exception specification carries a pointer to a FunctionDecl, and
the exception specification for that FunctionDecl is instantiated (if needed)
and used in the place of the function type's exception specification.
When a function template declaration with a non-trivial exception specification
is instantiated, the specialization's exception specification is set to this
new 'uninstantiated' kind rather than being instantiated immediately.
Expr::CanThrow has migrated onto Sema, so it can instantiate exception specs
on-demand. Also, any odr-use of a function triggers the instantiation of its
exception specification (the exception specification could be needed by IRGen).
In passing, fix two places where a DeclRefExpr was created but the corresponding
function was not actually marked odr-used. We used to get away with this, but
don't any more.
Also fix a bug where instantiating an exception specification which refers to
function parameters resulted in a crash. We still have the same bug in default
arguments, which I'll be looking into next.
This, plus a tiny patch to fix libstdc++'s common_type, is enough for clang to
parse (and, in very limited testing, support) all of libstdc++4.7's standard
headers.
llvm-svn: 154886
This diagnostic seems to be production ready, it's just an oversight that it
wasn't turned on by default.
The test changes are a bit of a mixed bag. Some tests that seemed like they
clearly didn't need to use this behavior have been modified not to use it.
Others that I couldn't be sure about, I added the necessary expected-warnings
to.
It's possible the diagnostic message could be improved to make it clearer that
this warning can be suppressed by using a value that won't lose precision when
converted to the target type (but can still be a floating point literal, such
as "bool b = 1.0;").
llvm-svn: 154068
the nested-name-specifier (e.g., because it is dependent), do not
error even though we can't represent it in the AST at this point.
This is a horrible, horrible hack. The actual feature we still need to
implement (for C++98!) is covered by PR12292. However, we used to
silently accept this code, so when we recently started rejecting it we
caused some regressions (e.g., <rdar://problem/11147355>). This hack
brings us back to the passable-but-not-good state we had previously.
llvm-svn: 153752
specialization is known to be incomplete. If we're asked to try to
complete it, don't attempt to instantiate it again -- that can lead
to stack overflow, and to rejects-valids if the class being incomplete
is not an error.
llvm-svn: 153236
Eli Friedman