[Bug c++/66786] [5/6 Regression] ICE: Segmentation fault
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66786 --- Comment #8 from Patrick Palka --- Author: ppalka Date: Mon Mar 7 17:09:53 2016 New Revision: 234038 URL: https://gcc.gnu.org/viewcvs?rev=234038=gcc=rev Log: Adjust fix for PR c++/66786 gcc/cp/ChangeLog: PR c++/66786 * pt.c (get_template_info): Handle PARM_DECL. (template_class_depth): Check DECL_P instead of VAR_OR_FUNCTION_DECL_P. Modified: trunk/gcc/cp/ChangeLog trunk/gcc/cp/pt.c
[Bug c++/66786] [5/6 Regression] ICE: Segmentation fault
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66786 Patrick Palka changed: What|Removed |Added Status|ASSIGNED|RESOLVED Resolution|--- |FIXED --- Comment #7 from Patrick Palka --- Fixed for GCC 6.
[Bug c++/66786] [5/6 Regression] ICE: Segmentation fault
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66786 --- Comment #6 from Patrick Palka --- Author: ppalka Date: Sat Mar 5 01:59:04 2016 New Revision: 233997 URL: https://gcc.gnu.org/viewcvs?rev=233997=gcc=rev Log: Fix PR c++/66786 (ICE with nested lambdas in variable template) gcc/cp/ChangeLog: PR c++/66786 * pt.c (template_class_depth): Given a lambda type, iterate into its LAMBDA_TYPE_EXTRA_SCOPE field instead of its TYPE_CONTEXT. Given a VAR_DECL, iterate into its CP_DECL_CONTEXT. gcc/testsuite/ChangeLog: PR c++/66786 * g++.dg/cpp1y/var-templ48.C: New test. * g++.dg/cpp1y/var-templ49.C: New test. Added: trunk/gcc/testsuite/g++.dg/cpp1y/var-templ48.C trunk/gcc/testsuite/g++.dg/cpp1y/var-templ49.C Modified: trunk/gcc/cp/ChangeLog trunk/gcc/cp/pt.c trunk/gcc/testsuite/ChangeLog
[Bug c++/66786] [5/6 Regression] ICE: Segmentation fault
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66786
Patrick Palka changed:
What|Removed |Added
Status|NEW |ASSIGNED
CC||ppalka at gcc dot gnu.org
Assignee|unassigned at gcc dot gnu.org |ppalka at gcc dot
gnu.org
--- Comment #4 from Patrick Palka ---
Slightly more simplified test case:
template auto list = [](T... xs) { [=](auto f) { f(xs...); };
};
int main() { list; }
The problem ultimately seems to lie in template_class_depth, which returns the
number of enclosing templates in which the given type or decl is embedded.
In particular, given the RECORD_TYPE that corresponds to the outermost lambda
in the above test case, template_class_depth returns 0 instead of 1 since the
TYPE_CONTEXT of this RECORD_TYPE is the file's TRANSLATION_UNIT_DECL and not
the VAR_DECL so template_class_depth never sees it.
That the TYPE_CONTEXT doesn't point to the enclosing VAR_DECL doesn't seem like
a bug because according to the documentation, the TYPE_CONTEXT (and
DECL_CONTEXT) of a tree is never expected to be a VAR_DECL. It can be a
FUNCTION_DECL however, which explains why the following test case, which just
replaces the enclosing variable template with a function template, compiles
successfully (the TYPE_CONTEXT points to the enclosing FUNCTION_DECL and so
template_class_depth appropriately returns 1):
template
auto
list ()
{
return [](T... xs) { [=](auto f) { f(xs...); }; };
}
int main() { list (); }
So I wonder how to make template_class_depth be aware of the given type's
enclosing variable template...
[Bug c++/66786] [5/6 Regression] ICE: Segmentation fault
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66786
--- Comment #5 from Patrick Palka ---
Looks like the field LAMBDA_TYPE_EXTRA_SCOPE has what we need. I am testing
this patch:
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 4d405cf..5c344c1 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -369,16 +369,20 @@ template_class_depth (tree type)
{
int depth;
- for (depth = 0;
- type && TREE_CODE (type) != NAMESPACE_DECL;
- type = (TREE_CODE (type) == FUNCTION_DECL)
-? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
+ for (depth = 0; type && TREE_CODE (type) != NAMESPACE_DECL; )
{
tree tinfo = get_template_info (type);
if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
&& uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo
++depth;
+
+ if (VAR_OR_FUNCTION_DECL_P (type))
+ type = CP_DECL_CONTEXT (type);
+ else if (LAMBDA_TYPE_P (type))
+ type = LAMBDA_TYPE_EXTRA_SCOPE (type);
+ else
+ type = CP_TYPE_CONTEXT (type);
}
return depth;
[Bug c++/66786] [5/6 Regression] ICE: Segmentation fault
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66786 Marek Polacek changed: What|Removed |Added Status|ASSIGNED|NEW Assignee|mpolacek at gcc dot gnu.org|unassigned at gcc dot gnu.org --- Comment #3 from Marek Polacek --- Unfortunately, I'll have to give up on this one. What happens here is that we ICE because we have a lambda expr, whose LAMBDA_EXPR_CAPTURE_LIST has null TREE_PURPOSE. 10272 /* We need to instantiate the capture list from the template 10273 after we've instantiated the closure members, but before we 10274 consider adding the conversion op. Also keep any captures 10275 that may have been added during instantiation of the op(). */ 10276 tree tmpl_expr = CLASSTYPE_LAMBDA_EXPR (pattern); 10277 tree tmpl_cap 10278 = tsubst_copy_and_build (LAMBDA_EXPR_CAPTURE_LIST (tmpl_expr), 10279 args, tf_warning_or_error, NULL_TREE, 10280 false, false); 10281 10282 LAMBDA_EXPR_CAPTURE_LIST (expr) 10283 = chainon (tmpl_cap, nreverse (LAMBDA_EXPR_CAPTURE_LIST (expr))); but tsubst_copy_and_build returns tmpl_cap without TREE_PURPOSE, because 16621 /* Expand the argument expressions. */ 16622 if (TREE_PURPOSE (t)) 16623 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args, 16624 complain, in_decl); returns null. That is probably because we end up calling 13898 /* Otherwise return the full NONTYPE_ARGUMENT_PACK that 13899 tsubst_decl put in the hash table. */ 13900 return retrieve_specialization (t, args, 0); which is where the null originates. Alas, this pt.c maze is something I can't figure out, so unassigning :(.
[Bug c++/66786] [5/6 Regression] ICE: Segmentation fault
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66786 Marek Polacek changed: What|Removed |Added Status|NEW |ASSIGNED CC||mpolacek at gcc dot gnu.org Assignee|unassigned at gcc dot gnu.org |mpolacek at gcc dot gnu.org --- Comment #2 from Marek Polacek --- I'll have a look...
[Bug c++/66786] [5/6 Regression] ICE: Segmentation fault
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66786 Richard Biener changed: What|Removed |Added Keywords||ice-on-valid-code Priority|P3 |P2 Target Milestone|6.0 |5.4
[Bug c++/66786] [5/6 Regression] ICE: Segmentation fault
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66786 Markus Trippelsdorf changed: What|Removed |Added Status|UNCONFIRMED |NEW Last reconfirmed||2015-08-31 CC||jason at gcc dot gnu.org Summary|[6 Regression] ICE: |[5/6 Regression] ICE: |Segmentation fault |Segmentation fault Ever confirmed|0 |1 --- Comment #1 from Markus Trippelsdorf --- Started with r214396.
