know how to recover from an error, we can attach a hint to the
diagnostic that states how to modify the code, which can be one of:
- Insert some new code (a text string) at a particular source
location
- Remove the code within a given range
- Replace the code within a given range with some new code (a text
string)
Right now, we use these hints to annotate diagnostic information. For
example, if one uses the '>>' in a template argument in C++98, as in
this code:
template<int I> class B { };
B<1000 >> 2> *b1;
we'll warn that the behavior will change in C++0x. The fix is to
insert parenthese, so we use code insertion annotations to illustrate
where the parentheses go:
test.cpp:10:10: warning: use of right-shift operator ('>>') in template
argument will require parentheses in C++0x
B<1000 >> 2> *b1;
^
( )
Use of these annotations is partially implemented for HTML
diagnostics, but it's not (yet) producing valid HTML, which may be
related to PR2386, so it has been #if 0'd out.
In this future, we could consider hooking this mechanism up to the
rewriter to actually try to fix these problems during compilation (or,
after a compilation whose only errors have fixes). For now, however, I
suggest that we use these code modification hints whenever we can, so
that we get better diagnostics now and will have better coverage when
we find better ways to use this information.
This also fixes PR3410 by placing the complaint about missing tokens
just after the previous token (rather than at the location of the next
token).
llvm-svn: 65570
vector<vector<double>> Matrix;
In C++98/03, this token always means "right shift". However, if we're in
a context where we know that it can't mean "right shift", provide a
friendly reminder to put a space between the two >'s and then treat it
as two >'s as part of recovery.
In C++0x, this token is always broken into two '>' tokens.
llvm-svn: 65484
std::vector<int>::allocator_type
When we parse a template-id that names a type, it will become either a
template-id annotation (which is a parsed representation of a
template-id that has not yet been through semantic analysis) or a
typename annotation (where semantic analysis has resolved the
template-id to an actual type), depending on the context. We only
produce a type in contexts where we know that we only need type
information, e.g., in a type specifier. Otherwise, we create a
template-id annotation that can later be "upgraded" by transforming it
into a typename annotation when the parser needs a type. This occurs,
for example, when we've parsed "std::vector<int>" above and then see
the '::' after it. However, it means that when writing something like
this:
template<> class Outer::Inner<int> { ... };
We have two tokens to represent Outer::Inner<int>: one token for the
nested name specifier Outer::, and one template-id annotation token
for Inner<int>, which will be passed to semantic analysis to define
the class template specialization.
Most of the churn in the template tests in this patch come from an
improvement in our error recovery from ill-formed template-ids.
llvm-svn: 65467
us whether there was an error in trying to parse a type-name (type-id
in C++). This allows propagation of errors further in the compiler,
suppressing more bogus error messages.
llvm-svn: 64922
any named parameters, e.g., this is accepted in C:
void f(...) __attribute__((overloadable));
although this would be rejected:
void f(...);
To do this, moved the checking of the "ellipsis without any named
arguments" condition from the parser into Sema (where it belongs anyway).
llvm-svn: 64902
specialization of class templates, e.g.,
template<typename T> class X;
template<> class X<int> { /* blah */ };
Each specialization is a different *Decl node (naturally), and can
have different members. We keep track of forward declarations and
definitions as for other class/struct/union types.
This is only the basic framework: we still have to deal with checking
the template headers properly, improving recovery when there are
failures, handling nested name specifiers, etc.
llvm-svn: 64848
1) implement parser and sema support for reading and verifying attribute(warnunusedresult).
2) rename hasLocalSideEffect to isUnusedResultAWarning, inverting the sense
of its result.
3) extend isUnusedResultAWarning to directly return the loc and range
info that should be reported to the user. Make it substantially more
precise in some cases than what was previously reported.
4) teach isUnusedResultAWarning about CallExpr to decls that are
pure/const/warnunusedresult, fixing a fixme.
5) change warn_attribute_wrong_decl_type to not pass in english strings, instead,
pass in integers and use %select.
llvm-svn: 64543
This commit adds a new attribute, "overloadable", that enables C++
function overloading in C. The attribute can only be added to function
declarations, e.g.,
int *f(int) __attribute__((overloadable));
If the "overloadable" attribute exists on a function with a given
name, *all* functions with that name (and in that scope) must have the
"overloadable" attribute. Sets of overloaded functions with the
"overloadable" attribute then follow the normal C++ rules for
overloaded functions, e.g., overloads must have different
parameter-type-lists from each other.
When calling an overloaded function in C, we follow the same
overloading rules as C++, with three extensions to the set of standard
conversions:
- A value of a given struct or union type T can be converted to the
type T. This is just the identity conversion. (In C++, this would
go through a copy constructor).
- A value of pointer type T* can be converted to a value of type U*
if T and U are compatible types. This conversion has Conversion
rank (it's considered a pointer conversion in C).
- A value of type T can be converted to a value of type U if T and U
are compatible (and are not both pointer types). This conversion
has Conversion rank (it's considered to be a new kind of
conversion unique to C, a "compatible" conversion).
Known defects (and, therefore, next steps):
1) The standard-conversion handling does not understand conversions
involving _Complex or vector extensions, so it is likely to get
these wrong. We need to add these conversions.
2) All overloadable functions with the same name will have the same
linkage name, which means we'll get a collision in the linker (if
not sooner). We'll need to mangle the names of these functions.
llvm-svn: 64336
arguments. This commit covers checking and merging default template
arguments from previous declarations, but it does not cover the actual
use of default template arguments when naming class template
specializations.
llvm-svn: 64229
disambiguation contexts, so that we properly parse template arguments
such as
A<int()>
as type-ids rather than as expressions. Since this can be confusing
(especially when the template parameter is a non-type template
parameter), we try to give a friendly error message.
Almost, eliminate a redundant error message (that should have been a
note) and add some ultra-basic checks for non-type template
arguments.
llvm-svn: 64189
representation for template arguments. Also simplifies the interface
for ActOnClassTemplateSpecialization and eliminates some annoying
allocations of TemplateArgs.
My attempt at smart pointers for template arguments lists is
relatively lame. We can improve it once we're sure that we have the
right representation for template arguments.
llvm-svn: 64154
to a class template. For example, the template-id 'vector<int>' now
has a nice, sugary type in the type system. What we can do now:
- Parse template-ids like 'vector<int>' (where 'vector' names a
class template) and form proper types for them in the type system.
- Parse icky template-ids like 'A<5>' and 'A<(5 > 0)>' properly,
using (sadly) a bool in the parser to tell it whether '>' should
be treated as an operator or not.
This is a baby-step, with major problems and limitations:
- There are currently two ways that we handle template arguments
(whether they are types or expressions). These will be merged, and,
most likely, TemplateArg will disappear.
- We don't have any notion of the declaration of class template
specializations or of template instantiations, so all template-ids
are fancy names for 'int' :)
llvm-svn: 64153
than a Decl, which gives us some more flexibility to express the
results with the type system. There are no clients using this
flexibility yet, but it's meant to be able to describe qualified names
as written in the source (e.g., "foo::type") or template-ids that name
a class template specialization (e.g., "std::vector<INT>").
DeclSpec's TST_typedef has become TST_typename, to reflect its use to
describe types found by name (that may or may not be typedefs). The
type representation of a DeclSpec with TST_typename is an opaque
QualType pointer. All users of TST_typedef, both direct and indirect,
have been updated for these changes.
llvm-svn: 64141
redeclarations. For example, checks that a class template
redeclaration has the same template parameters as previous
declarations.
Detangled class-template checking from ActOnTag, whose logic was
getting rather convoluted because it tried to handle C, C++, and C++
template semantics in one shot.
Made some inroads toward eliminating extraneous "declaration does not
declare anything" errors by adding an "error" type specifier.
llvm-svn: 63973
This shrinks OwningResult by one pointer. Since it is no longer larger than OwningPtr, merge the two.
This leads to simpler client code and speeds up my benchmark by 2.7%.
For some reason, this exposes a previously hidden bug, causing a regression in SemaCXX/condition.cpp.
llvm-svn: 63867
Steve Naroff