From d132b74abae28ef6dafb6d194d32c838b204db77 Mon Sep 17 00:00:00 2001 From: Jason Merrill Date: Thu, 14 Feb 2013 20:27:12 -0500 Subject: [PATCH] re PR c++/55220 ([c++11] ICE when doing partial template specialization on variadic template) PR c++/55220 * pt.c (unify): A pack expansion that is not the last template argument makes the entire template argument list non-deduced. From-SVN: r196068 --- gcc/cp/ChangeLog | 4 +++ gcc/cp/pt.c | 8 ++++++ .../g++.dg/cpp0x/variadic-nondeduce2.C | 25 +++++++++++++++++++ 3 files changed, 37 insertions(+) create mode 100644 gcc/testsuite/g++.dg/cpp0x/variadic-nondeduce2.C diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 76cefcf848b..1ecbb7b0b1a 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,5 +1,9 @@ 2013-02-14 Jason Merrill + PR c++/55220 + * pt.c (unify): A pack expansion that is not the last template + argument makes the entire template argument list non-deduced. + PR c++/56323 * name-lookup.c (do_class_using_decl): Handle typedefs with inheriting constructors. diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index e88ea855694..440df1ea231 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -16548,6 +16548,14 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict, && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1))) parm_variadic_p = 1; + for (i = 0; i < len - parm_variadic_p; ++i) + /* If the template argument list of P contains a pack + expansion that is not the last template argument, the + entire template argument list is a non-deduced + context. */ + if (PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, i))) + return unify_success (explain_p); + if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p) return unify_too_few_arguments (explain_p, TREE_VEC_LENGTH (argvec), len); diff --git a/gcc/testsuite/g++.dg/cpp0x/variadic-nondeduce2.C b/gcc/testsuite/g++.dg/cpp0x/variadic-nondeduce2.C new file mode 100644 index 00000000000..a82a098c3da --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/variadic-nondeduce2.C @@ -0,0 +1,25 @@ +// PR c++/55220 +// { dg-do compile { target c++11 } } + +template struct something_like_tuple +{ + +}; + +template struct is_last +{ + static const bool value = false; +}; + +// Head is non-deducible, so this can't work as the user intended +template class Tuple, typename ... Head> +struct is_last> +{ + static const bool value = true; +}; + +#define SA(X) static_assert (X, #X) + +typedef something_like_tuple something_like_tuple_t; +SA ((is_last::value == false)); +SA ((is_last::value == false)); -- 2.30.2