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
This change refactors and cleans up our handling of name lookup with
LookupDecl. There are several aspects to this refactoring:
- The criteria for name lookup is now encapsulated into the class
LookupCriteria, which replaces the hideous set of boolean values
that LookupDecl currently has.
- The results of name lookup are returned in a new class
LookupResult, which can lazily build OverloadedFunctionDecls for
overloaded function sets (and, eventually, eliminate the need to
allocate member for OverloadedFunctionDecls) and contains a
placeholder for handling ambiguous name lookup (for C++).
- The primary entry points for name lookup are now LookupName (for
unqualified name lookup) and LookupQualifiedName (for qualified
name lookup). There is also a convenience function
LookupParsedName that handles qualified/unqualified name lookup
when given a scope specifier. Together, these routines are meant
to gradually replace the kludgy LookupDecl, but this won't happen
until after we have base class lookup (which forces us to cope
with ambiguities).
- Documented the heck out of name lookup. Experimenting a little
with using Doxygen's member groups to make some sense of the Sema
class. Feedback welcome!
- Fixes some lingering issues with name lookup for
nested-name-specifiers, which now goes through
LookupName/LookupQualifiedName.
llvm-svn: 62245
- Simplify ParseDeclCXX to use early exit on error instead of nesting.
- Change ParseDeclCXX to using the 'skip on error' form of ExpectAndConsume.
- If we don't see the ; in a using directive, still call the action, for
hopefully better error recovery.
llvm-svn: 61801
Douglas Gregor