Re: [c++-concepts] requires expressions
Committed. On Fri, Jul 26, 2013 at 10:27 PM, Gabriel Dos Reis g...@axiomatics.org wrote: Andrew Sutton andrew.n.sut...@gmail.com writes: | Fixed and committed, but I have a small follow-up related to parameter | packs in requires clauses. The checking for unexpanded parameter packs | treats the parameter declarations like regular PARM_DECL references | and gives errors that they are unexpanded packs. | | 2013-07-26 Andrew Sutton andrew.n.sut...@gmail.com | * gcc/cp/tree.c (cp_walk_subtrees): Don't recurse through the | requires expr parameter list. | | Andrew Let me know when you commit this so I can merge from trunk. -- Gaby -- Andrew Sutton andrew.n.sut...@gmail.com
Re: [c++-concepts] requires expressions
Fixed and committed, but I have a small follow-up related to parameter packs in requires clauses. The checking for unexpanded parameter packs treats the parameter declarations like regular PARM_DECL references and gives errors that they are unexpanded packs. 2013-07-26 Andrew Sutton andrew.n.sut...@gmail.com * gcc/cp/tree.c (cp_walk_subtrees): Don't recurse through the requires expr parameter list. Andrew On Thu, Jul 25, 2013 at 3:49 PM, Jason Merrill ja...@redhat.com wrote: On 07/25/2013 10:19 AM, Andrew Sutton wrote: + pp_cxx_parameter_declaration_clause(pp, TREE_OPERAND (t, 0)); Space before (. Otherwise, looks good. Jason -- Andrew Sutton andrew.n.sut...@gmail.com requires-8.patch Description: Binary data
Re: [c++-concepts] requires expressions
Makes sense. Jason
Re: [c++-concepts] requires expressions
Andrew Sutton andrew.n.sut...@gmail.com writes: | Fixed and committed, but I have a small follow-up related to parameter | packs in requires clauses. The checking for unexpanded parameter packs | treats the parameter declarations like regular PARM_DECL references | and gives errors that they are unexpanded packs. | | 2013-07-26 Andrew Sutton andrew.n.sut...@gmail.com | * gcc/cp/tree.c (cp_walk_subtrees): Don't recurse through the | requires expr parameter list. | | Andrew Let me know when you commit this so I can merge from trunk. -- Gaby
Re: [c++-concepts] requires expressions
On 07/25/2013 10:19 AM, Andrew Sutton wrote: + pp_cxx_parameter_declaration_clause(pp, TREE_OPERAND (t, 0)); Space before (. Otherwise, looks good. Jason
Re: [c++-concepts] requires expressions
This should be merged with pp_cxx_parameter_declaration_clause. +reqparms_to_string (tree p) And this should have a more generic name. I called this parms_to_string for symmetry with args_to_string. It calls pp_cxx_parameter_declaration_clause. + if (check_requirements (t, args)) +return; + + ++processing_template_decl; + tree subst = instantiate_requirements (t, args); + --processing_template_decl; Surely you need to instantiate before checking, here and elsewhere. check_requirements will instantiate before evaluating. There are two instantiations on purpose. If checking succeeds, then there are no failures in this branch of constraint, so we don't need to recursively diagnose failures. The second generates a possibly invalid tree that is useful for emitting precise diagnostics, written in terms of the template arguments. Basically, it means I can generate this message: 'int::type' is not a valid type name. for failed nested type requirements. + inform (loc, %qE is not valid syntax, TREE_OPERAND (t, 0)); I don't think I would mention syntax here, since a syntax error would have been diagnosed at parse time rather than constraint checking time. is not a valid expression seems more appropriate. +// In an unevaluated context, the substitution of parm decls are not +// properly chained during substitution. Do that here. +static tree +fix_local_parms (tree sparms) A lot of the new code in pt.c doesn't seem like it needs to be there; let's put as much in constraint.cc as we can. Let's move some of the bits out of semantics.c as well. I think the [fixup|declare]_local_parms could move to semantics.c. Would you recommend moving tsubst_* for requirements into constraints.cc? Andrew
Re: [c++-concepts] requires expressions
On 07/13/2013 05:37 AM, Andrew Sutton wrote: There are two instantiations on purpose. OK. A lot of the new code in pt.c doesn't seem like it needs to be there; let's put as much in constraint.cc as we can. Let's move some of the bits out of semantics.c as well. I think the [fixup|declare]_local_parms could move to semantics.c. Would you recommend moving tsubst_* for requirements into constraints.cc? Yes, but I was thinking that [fixup|declare]_local_parms would go to constraints.cc as well. Both semantics.c and pt.c are too large already. Jason
Re: [c++-concepts] requires expressions
On 07/11/2013 02:59 PM, Andrew Sutton wrote: pp_cxx_requirement_parameter_list (cxx_pretty_printer *pp, tree t) This should be merged with pp_cxx_parameter_declaration_clause. +reqparms_to_string (tree p) And this should have a more generic name. + // requries clause. requires + if (check_requirements (t, args)) +return; + + ++processing_template_decl; + tree subst = instantiate_requirements (t, args); + --processing_template_decl; Surely you need to instantiate before checking, here and elsewhere. + inform (loc, %qE is not valid syntax, TREE_OPERAND (t, 0)); I don't think I would mention syntax here, since a syntax error would have been diagnosed at parse time rather than constraint checking time. +// In an unevaluated context, the substitution of parm decls are not +// properly chained during substitution. Do that here. +static tree +fix_local_parms (tree sparms) A lot of the new code in pt.c doesn't seem like it needs to be there; let's put as much in constraint.cc as we can. Let's move some of the bits out of semantics.c as well. Incidentally, I notice a funny thing about the headers of the new files: /* Process declarations and variables for C++ compiler. ... // Components for processing constraints and evaluating constraints. The second line should move to the top of the file, replacing the first line. Jason
[c++-concepts] requires expressions
The attached patch finishes the semantics for requires expressions. It includes reduction rules for constraint decomposition, substitution rules, and diagnostics. Andrew Changelog: 2013-07-11 Andrew Sutton andrew.n.sut...@gmail.com * gcc/cp/cp-tree.h (declare_local_parms): New * gcc/cp/cp-tree.h (finish_validtype_expr): Fixed typo. * gcc/cp/semantics.c (potential_constant_expr): Return true for requirements. (finish_requires_expr): Actually evaluate when we are not processing a template decl. * pt.c (tsubst_requires_expr): New, along with helper functions for instantiating requires parameters. (tsubst_validexpr_expr): New. (tsubst_validtype_expr): New. (tsubst_constexpr_expr): New. (tsubst_expr_req): New. (tsubst_type_req): New. (tsubst_nested_req): New. (tsubst_copy_and_build): Substitution rules for requirements. (instantiate_requirements): Do not require a constant expression. * constraint.cc (redcue_requires): Reduction rules for requires expressions and requirement nodes. (reduce_stmt_list): Remove redundant checks. (diagnose_requires): Diagnose failures in requires expressions and specific kinds of expressions. * gcc/cp/cxx-pretty-print.c (pp_cxx_primary_expression): Pretty print expressions related to requirements (pp_cxx_requirement_parameter_list). Clean up implementation. * gcc/cp/cxx-pretty-print.h (pp_cxx_requirement_parameter_list): New, along with pretty printers for requirements-related expressions. * gcc/cp/error.c (dump_expr): Dump expressions related to requirements. (reqparms_to_string): New. (cp_printer): Use %Z to print a list of parameters. reqexpr-6.patch Description: Binary data
