| Message ID | 863ac97a-8780-89da-03b2-82b060b00cb5@acm.org |
|---|---|
| State | New |
| Headers | show |
| Series | [PR,c+,94827] : template parm with default requires | expand |
On 4/29/20 2:50 PM, Nathan Sidwell wrote: > Jason, > this is the patch you suggested, as I understood it. I kept > finish_nested_require's saving of the (converted) > current_template_parms, becase of the comment about use in diagnostics. > this extended test that tries to call the function ices with the patch. So not there yet. nathan
On 4/29/20 2:50 PM, Nathan Sidwell wrote: > Jason, > this is the patch you suggested, as I understood it. I kept > finish_nested_require's saving of the (converted) > current_template_parms, becase of the comment about use in diagnostics. > > Is this what you meant? Yes, this looks fine. But I don't think that we need to keep saving the converted current_template_parms; diagnostics could also normalize using NULL_TREE args. And it looks like diagnose_nested_requirement isn't currently doing re-normalization anyway. This doesn't need to block the release, though. Jason
On 4/30/20 10:18 AM, Jason Merrill wrote: > On 4/29/20 2:50 PM, Nathan Sidwell wrote: >> Jason, >> this is the patch you suggested, as I understood it. I kept >> finish_nested_require's saving of the (converted) >> current_template_parms, becase of the comment about use in diagnostics. >> >> Is this what you meant? > > Yes, this looks fine. > > But I don't think that we need to keep saving the converted > current_template_parms; diagnostics could also normalize using NULL_TREE > args. And it looks like diagnose_nested_requirement isn't currently > doing re-normalization anyway. This doesn't need to block the release, > though. Ok, I'll deal with that post-release. Here's a modified version. The only change is to remove an assert in tsubst_nested_requirement. We have an arg_vec of 2, but only the first is filled in. Thus we think the NULL one is a dependent type. The testcase checks we evaluate the default arg as expected. I don't expect the bootstrap to fail, because this is removing an assert. nathan
On 4/30/20 10:35 AM, Nathan Sidwell wrote: > On 4/30/20 10:18 AM, Jason Merrill wrote: >> On 4/29/20 2:50 PM, Nathan Sidwell wrote: >>> Jason, >>> this is the patch you suggested, as I understood it. I kept >>> finish_nested_require's saving of the (converted) >>> current_template_parms, becase of the comment about use in diagnostics. >>> >>> Is this what you meant? >> >> Yes, this looks fine. >> >> But I don't think that we need to keep saving the converted >> current_template_parms; diagnostics could also normalize using >> NULL_TREE args. And it looks like diagnose_nested_requirement isn't >> currently doing re-normalization anyway. This doesn't need to block >> the release, though. > > Ok, I'll deal with that post-release. > > Here's a modified version. The only change is to remove an assert in > tsubst_nested_requirement. We have an arg_vec of 2, but only the first > is filled in. Thus we think the NULL one is a dependent type. > > The testcase checks we evaluate the default arg as expected. > > I don't expect the bootstrap to fail, because this is removing an assert. indeed it didn't. The patch is pushed to trunk nathan
2020-04-27 Jason Merrill <jason@redhat.com> Nathan Sidwell <nathan@acm.org> PR c++/94827 * constraint.cc (map_arguments): If ARGS is null, it's a self-mapping of parms. (finish_nested_requirement): Do not pass argified current_template_parms to normalization. diff --git c/gcc/cp/constraint.cc w/gcc/cp/constraint.cc index 06161b8c8c4..a6009dc0c47 100644 --- c/gcc/cp/constraint.cc +++ w/gcc/cp/constraint.cc @@ -546,12 +546,16 @@ static tree map_arguments (tree parms, tree args) { for (tree p = parms; p; p = TREE_CHAIN (p)) - { - int level; - int index; - template_parm_level_and_index (TREE_VALUE (p), &level, &index); - TREE_PURPOSE (p) = TMPL_ARG (args, level, index); - } + if (args) + { + int level; + int index; + template_parm_level_and_index (TREE_VALUE (p), &level, &index); + TREE_PURPOSE (p) = TMPL_ARG (args, level, index); + } + else + TREE_PURPOSE (p) = TREE_VALUE (p); + return parms; } @@ -2953,12 +2957,15 @@ finish_compound_requirement (location_t loc, tree expr, tree type, bool noexcept tree finish_nested_requirement (location_t loc, tree expr) { + /* Currently open template headers have dummy arg vectors, so don't + pass into normalization. */ + tree norm = normalize_constraint_expression (expr, NULL_TREE, false); + tree args = current_template_parms + ? template_parms_to_args (current_template_parms) : NULL_TREE; + /* Save the normalized constraint and complete set of normalization arguments with the requirement. We keep the complete set of arguments around for re-normalization during diagnostics. */ - tree args = current_template_parms - ? template_parms_to_args (current_template_parms) : NULL_TREE; - tree norm = normalize_constraint_expression (expr, args, false); tree info = build_tree_list (args, norm); /* Build the constraint, saving its normalization as its type. */ diff --git c/gcc/testsuite/g++.dg/concepts/pr94827.C w/gcc/testsuite/g++.dg/concepts/pr94827.C new file mode 100644 index 00000000000..a6c147bf303 --- /dev/null +++ w/gcc/testsuite/g++.dg/concepts/pr94827.C @@ -0,0 +1,7 @@ +// PR 94287 ICE looking inside open template-parm level +// { dg-do compile { target c++17 } } +// { dg-options -fconcepts } +template <typename T, + bool = requires { requires (sizeof(T)==0); } > +void foo(T) {} +