Hello, In the example of this problem report, during the substituting of int into 'function', tsubst_aggr_type fails for the alias ctxt1. This is because TYPE_TEMPLATE_INFO looks for the TEMPLATE_INFO of the ctxt1 alias at the wrong place and was wrongly finding it to be NULL. Namely, it was looking for it in the DECL_TEMPLATE_INFO of the declaration of the type -- as if ctxt1 was an alias template specialization -- rather than looking of it in its CLASSTYPE_TEMPLATE_INFO.
Fixed thus. The second hunk of the patch is just to prevent the compiler from crashing when primary_template_instantiation_p is passed an alias of a class template instantiation. Bootstrapped and tested on x86_64-unknown-linux-gnu against trunk. gcc/cp * cp-tree.h (TYPE_TEMPLATE_INFO): For an alias that is not an instance of alias template, don't look for its TEMPLATE_INFO in its declaration. * pt.c (primary_template_instantiation_p): Don't crash on an alias that is not an instance of a template. gcc/testsuite/ * g++.dg/cpp0x/alias-decl-21.C: New test. --- gcc/cp/cp-tree.h | 4 ++-- gcc/cp/pt.c | 1 + gcc/testsuite/g++.dg/cpp0x/alias-decl-21.C | 24 ++++++++++++++++++++++++ 3 files changed, 27 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp0x/alias-decl-21.C diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index 44f3ac1..64a8830 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -2634,8 +2634,8 @@ extern void decl_shadowed_for_var_insert (tree, tree); template info for the alias template, not the one (if any) for the template of the underlying type. */ #define TYPE_TEMPLATE_INFO(NODE) \ - (TYPE_ALIAS_P (NODE) \ - ? ((TYPE_NAME (NODE) && DECL_LANG_SPECIFIC (TYPE_NAME (NODE))) \ + ((TYPE_ALIAS_P (NODE) && DECL_LANG_SPECIFIC (TYPE_NAME (NODE))) \ + ? (DECL_LANG_SPECIFIC (TYPE_NAME (NODE)) \ ? DECL_TEMPLATE_INFO (TYPE_NAME (NODE)) \ : NULL_TREE) \ : ((TREE_CODE (NODE) == ENUMERAL_TYPE) \ diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index ad81bab..3163bd4 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -2854,6 +2854,7 @@ primary_template_instantiation_p (const_tree t) else if (TYPE_P (t) && TYPE_TEMPLATE_INFO (t) && PRIMARY_TEMPLATE_P (TYPE_TI_TEMPLATE (t)) + && DECL_LANG_SPECIFIC (TYPE_NAME (t)) && DECL_TEMPLATE_INSTANTIATION (TYPE_NAME (t))) return true; return false; diff --git a/gcc/testsuite/g++.dg/cpp0x/alias-decl-21.C b/gcc/testsuite/g++.dg/cpp0x/alias-decl-21.C new file mode 100644 index 0000000..b68fa93 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/alias-decl-21.C @@ -0,0 +1,24 @@ +// Origin: PR c++/53540 +// { dg-do compile { target c++11 } } + +template <typename T> +struct context +{ + typedef int type; +}; + +template <typename T> +void function() +{ + using ctx1 = context<T>; + typename ctx1::type f1; + + typedef context<T> ctx2; + typename ctx2::type f2; +} + +int main() +{ + function<int>(); +} + -- Dodji