From e76b247239756b547eaa51d9fa0629416a293269 Mon Sep 17 00:00:00 2001 From: Jason Merrill Date: Wed, 6 Sep 2017 21:02:46 -0400 Subject: [PATCH] PR c++/82053 - ICE with default argument in lambda in template * pt.c (tsubst_arg_types): Substitute default arguments for lambdas in templates. (retrieve_specialization): Use lambda_fn_in_template_p. * cp-tree.h: Declare it. From-SVN: r251826 --- gcc/cp/ChangeLog | 6 ++++++ gcc/cp/cp-tree.h | 1 + gcc/cp/pt.c | 21 ++++++++++----------- gcc/testsuite/g++.dg/cpp1y/lambda-defarg7.C | 13 +++++++++++++ 4 files changed, 30 insertions(+), 11 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp1y/lambda-defarg7.C diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index e497094c4d5..6c4a31d7850 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,5 +1,11 @@ 2017-09-06 Jason Merrill + PR c++/82053 - ICE with default argument in lambda in template + * pt.c (tsubst_arg_types): Substitute default arguments for lambdas + in templates. + (retrieve_specialization): Use lambda_fn_in_template_p. + * cp-tree.h: Declare it. + PR c++/82070 - error with nested lambda capture * pt.c (tsubst_expr) [DECL_EXPR]: Register capture proxies with register_local_specialization. diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index 20fa03915c5..a0e31d3d19d 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -6821,6 +6821,7 @@ extern tree current_nonlambda_function (void); extern tree nonlambda_method_basetype (void); extern tree current_nonlambda_scope (void); extern bool generic_lambda_fn_p (tree); +extern bool lambda_fn_in_template_p (tree); extern void maybe_add_lambda_conv_op (tree); extern bool is_lambda_ignored_entity (tree); extern bool lambda_static_thunk_p (tree); diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index 4a65e31b661..ec7bbc890c6 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -1193,16 +1193,8 @@ retrieve_specialization (tree tmpl, tree args, hashval_t hash) /* Lambda functions in templates aren't instantiated normally, but through tsubst_lambda_expr. */ - if (LAMBDA_FUNCTION_P (tmpl)) - { - bool generic = PRIMARY_TEMPLATE_P (tmpl); - if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)) > generic) - return NULL_TREE; - - /* But generic lambda functions are instantiated normally, once their - containing context is fully instantiated. */ - gcc_assert (generic); - } + if (lambda_fn_in_template_p (tmpl)) + return NULL_TREE; if (optimize_specialization_lookup_p (tmpl)) { @@ -12579,7 +12571,7 @@ tsubst_template_decl (tree t, tree args, tsubst_flags_t complain, bool lambda_fn_in_template_p (tree fn) { - if (!LAMBDA_FUNCTION_P (fn)) + if (!fn || !LAMBDA_FUNCTION_P (fn)) return false; tree closure = DECL_CONTEXT (fn); return CLASSTYPE_TEMPLATE_INFO (closure) != NULL_TREE; @@ -13248,6 +13240,13 @@ tsubst_arg_types (tree arg_types, done in build_over_call. */ default_arg = TREE_PURPOSE (arg_types); + /* Except that we do substitute default arguments under tsubst_lambda_expr, + since the new op() won't have any associated template arguments for us + to refer to later. */ + if (lambda_fn_in_template_p (in_decl)) + default_arg = tsubst_copy_and_build (default_arg, args, complain, in_decl, + false/*fn*/, false/*constexpr*/); + if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG) { /* We've instantiated a template before its default arguments diff --git a/gcc/testsuite/g++.dg/cpp1y/lambda-defarg7.C b/gcc/testsuite/g++.dg/cpp1y/lambda-defarg7.C new file mode 100644 index 00000000000..f67dfee8fdf --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp1y/lambda-defarg7.C @@ -0,0 +1,13 @@ +// PR c++/82053 +// { dg-do compile { target c++14 } } + +template +int fn() { return 42; } + +template +auto lam = [](int = fn()){}; + +int main() +{ + lam(); +} -- 2.30.2