From 75a27d3584e4c8565a838d4623e12ba1602e8a92 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Sun, 31 Jan 2016 15:53:26 +0100 Subject: [PATCH] re PR c++/68763 (ICE: in verify_unstripped_args, at cp/pt.c:1132) PR c++/68763 * tree.c (strip_typedefs) [FUNCTION_TYPE]: Avoid building a new function type if nothing is changing. Co-Authored-By: Jason Merrill From-SVN: r233020 --- gcc/cp/ChangeLog | 7 +++++++ gcc/cp/tree.c | 38 ++++++++++++++++++++++++++++++++++---- 2 files changed, 41 insertions(+), 4 deletions(-) diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 783fe72ff53..804deb068ef 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,10 @@ +2016-01-31 Jakub Jelinek + Jason Merrill + + PR c++/68763 + * tree.c (strip_typedefs) [FUNCTION_TYPE]: Avoid building a new + function type if nothing is changing. + 2016-01-31 Jason Merrill PR c++/69009 diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c index d4cf3102a03..2bf37bcabc1 100644 --- a/gcc/cp/tree.c +++ b/gcc/cp/tree.c @@ -1314,7 +1314,22 @@ strip_typedefs (tree t, bool *remove_attributes) case FUNCTION_TYPE: case METHOD_TYPE: { - tree arg_types = NULL, arg_node, arg_type; + tree arg_types = NULL, arg_node, arg_node2, arg_type; + bool changed; + + /* Because we stomp on TREE_PURPOSE of TYPE_ARG_TYPES in many places + around the compiler (e.g. cp_parser_late_parsing_default_args), we + can't expect that re-hashing a function type will find a previous + equivalent type, so try to reuse the input type if nothing has + changed. If the type is itself a variant, that will change. */ + bool is_variant = typedef_variant_p (t); + if (remove_attributes + && (TYPE_ATTRIBUTES (t) || TYPE_USER_ALIGN (t))) + is_variant = true; + + type = strip_typedefs (TREE_TYPE (t), remove_attributes); + changed = type != TREE_TYPE (t) || is_variant; + for (arg_node = TYPE_ARG_TYPES (t); arg_node; arg_node = TREE_CHAIN (arg_node)) @@ -1324,11 +1339,27 @@ strip_typedefs (tree t, bool *remove_attributes) arg_type = strip_typedefs (TREE_VALUE (arg_node), remove_attributes); gcc_assert (arg_type); + if (arg_type == TREE_VALUE (arg_node) && !changed) + continue; - arg_types = - tree_cons (TREE_PURPOSE (arg_node), arg_type, arg_types); + if (!changed) + { + changed = true; + for (arg_node2 = TYPE_ARG_TYPES (t); + arg_node2 != arg_node; + arg_node2 = TREE_CHAIN (arg_node2)) + arg_types + = tree_cons (TREE_PURPOSE (arg_node2), + TREE_VALUE (arg_node2), arg_types); + } + + arg_types + = tree_cons (TREE_PURPOSE (arg_node), arg_type, arg_types); } + if (!changed) + return t; + if (arg_types) arg_types = nreverse (arg_types); @@ -1337,7 +1368,6 @@ strip_typedefs (tree t, bool *remove_attributes) if (arg_node) arg_types = chainon (arg_types, void_list_node); - type = strip_typedefs (TREE_TYPE (t), remove_attributes); if (TREE_CODE (t) == METHOD_TYPE) { tree class_type = TREE_TYPE (TREE_VALUE (arg_types));