Or, do not set Sema's CurContext to the template declaration's when substituting into default template arguments of said template declaration.
If we do push the template declaration context on to Sema, and the template declaration is at namespace scope, Sema can get confused and try and do odr analysis when substituting into default template arguments, even though the substitution could be occurring within a dependent context.
I'm not sure why this was being done, perhaps there was concern that if a default template argument referred to a previous template parameter, it might not be found during substitution - but all regression tests pass, and I can't craft a test that would cause it to fails (if some one does, please inform me, and i'll craft a different fix for the PR).
This patch removes a single line of code, but unfortunately adds more than it removes, because of the tests. Some day I still hope to commit a patch that removes far more lines than it adds, while leaving clang better for it ;)
Sorry that r253590 ("Change the expression evaluation context from Unevaluated to ConstantEvaluated while substituting into non-type template argument defaults") caused the PR!
llvm-svn: 258110
Summary:
`OpaqueValueExpr`s may not have a source expression (as in the case when
they are created due to a default argument error).
This can cause an assertion failure in `TransformOpaqueValueExpr` during
template instantiation.
This patch fixes the assertion failure.
Reviewers: hfinkel, rsmith
Subscribers: fraggamuffin, cfe-commits
Differential Revision: http://reviews.llvm.org/D11582
Patch by Rachel Craik!
llvm-svn: 246600
If a function declaration is found inside a template function as in:
template<class T> void f() {
void g(int x = T::v) except(T::w);
}
it must be instantiated along with the enclosing template function,
including default arguments and exception specification.
Together with the patch committed in r240974 this implements DR1484.
Differential Revision: http://reviews.llvm.org/D11194
llvm-svn: 245810
Summary:
We would not perform substitution at an appropriate point, allowing strange
results to appear. We would accepts things that we shouldn't or mangle things incorrectly. Note that this hasn't fixed the other cases like
template-template parameters or non-type template parameters.
Reviewers: doug.gregor, rjmccall, rsmith
Reviewed By: rsmith
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1507
llvm-svn: 189540
before the template parameters have acquired a proper context (e.g.,
because the enclosing context has yet to be built), provide empty
parameter lists for all outer template parameter scopes to inhibit any
substitution for those template parameters. Fixes PR9643 /
<rdar://problem/9251019>.
llvm-svn: 133055
- This is designed to make it obvious that %clang_cc1 is a "test variable"
which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
can be useful to redefine what gets run as 'clang -cc1' (for example, to set
a default target).
llvm-svn: 91446
annotation token, because some of the tokens we're annotating might
not be in the set of cached tokens (we could have consumed them
unconditionally).
Also, move the tentative parsing from ParseTemplateTemplateArgument
into the one caller that needs it, improving recovery.
llvm-svn: 86904
with its corresponding template parameter. This can happen when we
performed some substitution into the default template argument and
what we had doesn't match any more, e.g.,
template<int> struct A;
template<typename T, template<T> class X = A> class B;
B<long> b;
Previously, we'd emit a pretty but disembodied diagnostic showing how
the default argument didn't match the template parameter. The
diagnostic was good, but nothing tied it to the *use* of the default
argument in "B<long>". This commit fixes that.
Also, tweak the counting of active template instantiations to avoid
counting non-instantiation records, such as those we create for
(surprise!) checking default arguments, instantiating default
arguments, and performing substitutions as part of template argument
deduction.
llvm-svn: 86884
template template parameter, substitute any prior template arguments
into the template template parameter. This, for example, allows us to
properly check the template template argument for a class such as:
template<typename T, template<T Value> class X> struct Foo;
The actual implementation of this feature was trivial; most of the
change is dedicated to giving decent diagnostics when this
substitution goes horribly wrong. We now get a note like:
note: while substituting prior template arguments into template
template parameter 'X' [with T = float]
As part of this change, enabled some very pedantic checking when
comparing template template parameter lists, which shook out a bug in
our overly-eager checking of default arguments of template template
parameters. We now perform only minimal checking of such default
arguments when they are initially parsed.
llvm-svn: 86864
nested-name-specifiers so that they don't gobble the template name (or
operator-function-id) unless there is also a
template-argument-list. For example, given
T::template apply
we would previously consume both "template" and "apply" as part of
parsing the nested-name-specifier, then error when we see that there
is no "<" starting a template argument list. Now, we parse such
constructs tentatively, and back off if the "<" is not present. This
allows us to parse dependent template names as one would use them for,
e.g., template template parameters:
template<typename T, template<class> class X = T::template apply>
struct MetaSomething;
Also, test default arguments for template template parameters.
llvm-svn: 86841
templates. The instantiation of these default arguments must be (and
now, is) delayed until the template argument is actually used, at
which point we substitute all levels of template arguments
concurrently.
llvm-svn: 86578
template, make sure to get the template that corresponds to *this*
declaration of the class template or specialization, rather than the
canonical specialization. Fixes PR5187.
llvm-svn: 84119
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
template specialization (e.g., std::vector<int> would now be
well-formed, since it relies on a default argument for the Allocator
template parameter).
This is much less interesting than one might expect, since (1) we're
not actually using the default arguments for anything important, such
as naming an actual Decl, and (2) we'll often need to instantiate the
default arguments to check their well-formedness. The real fun will
come later.
llvm-svn: 64310
Faisal Vali