Crash instantiating member template

[llvmbot]

Bugzilla Link	11421
Resolution	FIXED
Resolved on	Apr 25, 2012 13:42
Version	trunk
OS	Linux
Reporter	LLVM Bugzilla Contributor
CC	@akyrtzi,@DougGregor

Extended Description

template < unsigned > struct Combinatorial_map_base {
static const unsigned dimension = 3;
template struct One_dart_per_incident_cell_range: XXXXXXXXXdart_per_incident_cell_name {
};
};
typedef Combinatorial_map_base<3> LCC_3;
LCC_3::One_dart_per_incident_cell_range<>::iterator it;

$ clang++ -fsyntax-only a.ii
segfaults. It doesn't if I change the name starting with XXX.

(produced by delta, I still don't think that's the bug I am after...)

[llvmbot]

It looks like when you type the XXX name, clang thinks you just mistyped "One_dart_per_incident_cell_range" and it carries on valiantly as though you had typed "One_dart_per_incident_cell_range". So, here's a slightly smaller test case:

template struct B {
static const unsigned dimension = 3;
template struct A : A {};
};
B<0>::A<>::iterator it;

It still segfaults when you try to compile that. I'm very new to clang, but I managed to trace the problem to here: http://clang.llvm.org/doxygen/SemaDeclCXX_8cpp_source.html#l08409

Base->getType()->getAs() is returning null, so when you call getDecl() on it, bad things happen. Hope this helps. =)

[DougGregor]

This doesn't actually involve typo correction. This slightly-reduced example fails in the same way:

template < unsigned > struct X {
static const unsigned dimension = 3;
template
struct Y: Y { };
};
typedef X<3> X3;
X3::Y<>::iterator it;

[akyrtzi]

Fixed in r155576.