https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116253
--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by David Malcolm <dmalc...@gcc.gnu.org>: https://gcc.gnu.org/g:339246fb9ef4cac84126138093303f309071e40e commit r15-5995-g339246fb9ef4cac84126138093303f309071e40e Author: David Malcolm <dmalc...@redhat.com> Date: Fri Dec 6 13:40:55 2024 -0500 c++: use diagnostic nesting [PR116253] This patch uses the nested diagnostics capabilities added in the earlier patch in the C++ frontend. With this, and enabling the non-standard text formatting via: -fdiagnostics-set-output=text:experimental-nesting=yes and using: -std=c++20 -fconcepts-diagnostics-depth=2 then the output for the example in SG15's P3358R0 ("SARIF for Structured Diagnostics") is: P3358R0.C: In function âint main()â: P3358R0.C:26:6: error: no matching function for call to âpet(lizard)â 26 | pet(lizard{}); | ~~~^~~~~~~~~~ ⢠note: candidate: âtemplate<class auto:1> requires pettable<auto:1> void pet(auto:1)â P3358R0.C:21:6: 21 | void pet(pettable auto t); | ^~~ ⢠note: template argument deduction/substitution failed: ⢠note: constraints not satisfied ⢠P3358R0.C: In substitution of âtemplate<class auto:1> requires pettable<auto:1> void pet(auto:1) [with auto:1 = lizard]â: ⢠required from here P3358R0.C:26:6: 26 | pet(lizard{}); | ~~~^~~~~~~~~~ ⢠required for the satisfaction of âpettable<auto:1>â [with auto:1 = lizard] P3358R0.C:19:9: 19 | concept pettable = has_member_pet<T> or has_default_pet<T>; | ^~~~~~~~ ⢠note: no operand of the disjunction is satisfied P3358R0.C:19:38: 19 | concept pettable = has_member_pet<T> or has_default_pet<T>; | ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~ ⢠note: the operand âhas_member_pet<T>â is unsatisfied because P3358R0.C:19:20: 19 | concept pettable = has_member_pet<T> or has_default_pet<T>; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ⢠required for the satisfaction of âhas_member_pet<T>â [with T = lizard] P3358R0.C:13:9: 13 | concept has_member_pet = requires(T t) { t.pet(); }; | ^~~~~~~~~~~~~~ ⢠required for the satisfaction of âpettable<auto:1>â [with auto:1 = lizard] P3358R0.C:19:9: 19 | concept pettable = has_member_pet<T> or has_default_pet<T>; | ^~~~~~~~ ⢠in requirements with âT tâ [with T = lizard] P3358R0.C:13:26: 13 | concept has_member_pet = requires(T t) { t.pet(); }; | ^~~~~~~~~~~~~~~~~~~~~~~~~~ ⢠note: the required expression ât.pet()â is invalid, because P3358R0.C:13:47: 13 | concept has_member_pet = requires(T t) { t.pet(); }; | ~~~~~^~ ⢠error: âstruct lizardâ has no member named âpetâ P3358R0.C:13:44: 13 | concept has_member_pet = requires(T t) { t.pet(); }; | ~~^~~ ⢠note: the operand âhas_default_pet<T>â is unsatisfied because P3358R0.C:19:41: 19 | concept pettable = has_member_pet<T> or has_default_pet<T>; | ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~ ⢠required for the satisfaction of âhas_default_pet<T>â [with T = lizard] P3358R0.C:16:9: 16 | concept has_default_pet = T::is_pettable; | ^~~~~~~~~~~~~~~ ⢠required for the satisfaction of âpettable<auto:1>â [with auto:1 = lizard] P3358R0.C:19:9: 19 | concept pettable = has_member_pet<T> or has_default_pet<T>; | ^~~~~~~~ ⢠error: âis_pettableâ is not a member of âlizardâ P3358R0.C:16:30: 16 | concept has_default_pet = T::is_pettable; | ^~~~~~~~~~~ ⢠note: candidate: âvoid pet(dog)â P3358R0.C:9:6: 9 | void pet(dog); | ^~~ ⢠note: no known conversion for argument 1 from âlizardâ to âdogâ P3358R0.C:9:10: 9 | void pet(dog); | ^~~ ⢠note: candidate: âvoid pet(cat)â P3358R0.C:10:6: 10 | void pet(cat); | ^~~ ⢠note: no known conversion for argument 1 from âlizardâ to âcatâ P3358R0.C:10:10: 10 | void pet(cat); | ^~~ showing the hierarchical structure of the messages; ideally there would be a UI here allowing the user to expand/collapse the messages to drill out into the detail they are interested in. The structure is also captured in SARIF output (via the "nestingLevel" property). gcc/cp/ChangeLog: PR other/116253 * call.cc (print_conversion_rejection): Remove leading space from diagnostic messages. (print_conversion_rejection): Likewise. (print_arity_information): Likewise. (print_z_candidate): Likewise. Add auto_diagnostic_nesting_level before calls to fn_type_unification and diagnose_constraints. (print_z_candidates): Add auto_diagnostic_nesting_level before looping over candidates. (conversion_null_warnings): Remove leading space from diagnostic messages. (maybe_inform_about_fndecl_for_bogus_argument_init): Likewise. * constraint.cc (tsubst_valid_expression_requirement): Add auto_diagnostic_nesting_level when showing why the expression is invalid. (satisfy_disjunction): Likewise when showing operans, and again when replaying each branch of the disjunction. (diagnose_constraints): Likewise when replaying satisfaction. * error.cc (cp_diagnostic_text_starter): Set prefix. (print_instantiation_full_context): Only show the file if we're not showing nesting or the user has opted in to showing location information in nested diagnostics. (class auto_context_line): New. (print_instantiation_partial_context_line): Replace calls to print_location and to diagnostic_show_locus with an auto_context_line. (print_instantiation_partial_context): Replace calls to print_location with an auto_context_line. (maybe_print_constexpr_context): Likewise. (print_constrained_decl_info): Likewise. (print_concept_check_info): Likewise. (print_constraint_context_head): Likewise. (print_requires_expression_info): Likewise. gcc/testsuite/ChangeLog: PR other/116253 * g++.dg/concepts/nested-diagnostics-1-truncated.C: New test. * g++.dg/concepts/nested-diagnostics-1.C: New test. * g++.dg/concepts/nested-diagnostics-2.C: New test. Signed-off-by: David Malcolm <dmalc...@redhat.com>
