template name is not visible to unqualified lookup.
In order to support this without a severe degradation in our ability to
diagnose typos in template names, this change significantly restructures
the way we handle template-id-shaped syntax for which lookup of the
template name finds nothing.
Instead of eagerly diagnosing an undeclared template name, we now form a
placeholder template-name representing a name that is known to not find
any templates. When the parser sees such a name, it attempts to
disambiguate whether we have a less-than comparison or a template-id.
Any diagnostics or typo-correction for the name are delayed until its
point of use.
The upshot should be a small improvement of our diagostic quality
overall: we now take more syntactic context into account when trying to
resolve an undeclared identifier on the left hand side of a '<'. In
fact, this works well enough that the backwards-compatible portion (for
an undeclared identifier rather than a lookup that finds functions but
no function templates) is enabled in all language modes.
llvm-svn: 360308
For 'x::template y', consistently give a "no member named 'y' in 'x'"
diagnostic if there is no such member, and give a 'template keyword not
followed by a template' name error if there is such a member but it's not a
template. In the latter case, add a note pointing at the non-template.
Don't suggest inserting a 'template' keyword in 'X::Y<' if X is dependent
if the lookup of X::Y was actually not a dependent lookup and found only
non-templates.
llvm-svn: 332076
of a binary expression, continue on and parse the right-hand side of
the binary expression anyway, but don't call the semantic actions to
type-check. Previously, we would see the error and then, effectively,
skip tokens until the end of the statement.
The result should be more useful recovery, both in the normal case
(we'll actually see errors beyond the first one in a statement), but
it also helps code completion do a much better job, because we do
"real" code completion on the right-hand side of an invalid binary
expression rather than completing with the recovery completion. For
example, given
x = p->y
if there is no variable named "x", we can still complete after the p->
as a member expression. Along the recovery path, we would have
completed after the "->" as if we were in an expression context, which
is mostly useless.
llvm-svn: 114225
the required "template" keyword, using the same heuristics we do for
dependent template names in member access expressions, e.g.,
test/SemaTemplate/dependent-template-recover.cpp:11:8: error: use 'template'
keyword to treat 'getAs' as a dependent template name
T::getAs<U>();
^
template
Fixes PR5404.
llvm-svn: 104409
nested-name-specifier (e.g., "class T::foo") fails to find a tag
member in the scope nominated by the
nested-name-specifier. Previously, we gave a bland
error: 'Nested' does not name a tag member in the specified scope
which didn't actually say where we were looking, which was rather
horrible when the nested-name-specifier was instantiated. Now, we give
something a bit better:
error: no class named 'Nested' in 'NoDepBase<T>'
llvm-svn: 100060
therefore not creating ElaboratedTypes, which are still pretty-printed
with the written tag).
Most of these testcase changes were done by script, so don't feel too
sorry for my fingers.
llvm-svn: 98149
propagating error conditions out of the various annotate-me-a-snowflake
routines. Generally (but not universally) removes redundant diagnostics
as well as, you know, not crashing on bad code. On the other hand,
I have just signed myself up to fix fiddly parser errors for the next
week. Again.
llvm-svn: 97221
in a member access expression referring into the current instantiation
need not be resolved at template definition *if* the current
instantiation has any dependent base classes. Fixes PR6081.
llvm-svn: 93877
do not look into base classes if there are any dependent base
classes. Instead, note in the lookup result that we couldn't look into
any dependent bases. Use that new result kind to detect when this case
occurs, so that we can fall back to treating the type/value/etc. as a
member of an unknown specialization.
Fixes an issue where we were resolving lookup at template definition
time and then missing an ambiguity at template instantiation time.
llvm-svn: 93497
finds nothing), and the current instantiation has dependent base
classes, treat the qualified lookup as if it referred to an unknown
specialization. Fixes PR6031.
llvm-svn: 93433
name a template, when they occur in a base-specifier. This is one of
the (few) places where we know for sure that an identifier followed by
a '<' must be a template name, so we can diagnose and recover well:
test/SemaTemplate/dependent-base-classes.cpp:9:16: error: missing
'template'
keyword prior to dependent template name 'T::apply'
struct X1 : T::apply<U> { }; // expected-error{{missing 'template' ...
^
template
test/SemaTemplate/dependent-base-classes.cpp:12:13: error: unknown
template name
'vector'
struct X2 : vector<T> { }; // expected-error{{unknown template name
'vector'}}
^
2 diagnostics generated.
llvm-svn: 93257
initializers. This isn't actually in the C++ grammar (in any version),
but that's clearly an oversight: both GCC and EDG support this syntax,
and it's used within Boost code. I'll file a core issue proposing
precisely the change made here. Fixes PR6008.
llvm-svn: 93243