From 0be9efad938726721fd8c8c35609b1e1d7d30035 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Sun, 5 Apr 2020 00:28:28 +0200 Subject: [PATCH] debug: Improve debug info of c++14 deduced return type [PR94459] On the following testcase, in gdb ptype S::m1 prints long as return type, but all the other methods show void instead. PR53756 added code to add_type_attribute if the return type is auto/decltype(auto), but we actually should look through references, pointers and qualifiers. Haven't included there DW_TAG_atomic_type, because I think at least ATM one can't use that in C++. Not sure about DW_TAG_array_type or what else could be deduced. > http://eel.is/c++draft/dcl.spec.auto#3 says it has to appear as a > decl-specifier. > > http://eel.is/c++draft/temp.deduct.type#8 lists the forms where a template > argument can be deduced. > > Looks like you are missing arrays, pointers to members, and function return > types. 2020-04-04 Hannes Domani Jakub Jelinek PR debug/94459 * dwarf2out.c (gen_subprogram_die): Look through references, pointers, arrays, pointer-to-members, function types and qualifiers when checking if in-class DIE had an 'auto' or 'decltype(auto)' return type to emit type again on definition. * g++.dg/debug/pr94459.C: New test. Co-Authored-By: Hannes Domani --- gcc/ChangeLog | 9 +++++ gcc/dwarf2out.c | 15 ++++++- gcc/testsuite/ChangeLog | 6 +++ gcc/testsuite/g++.dg/debug/pr94459.C | 58 ++++++++++++++++++++++++++++ 4 files changed, 86 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/g++.dg/debug/pr94459.C diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 75e3a4f3993..9501c946cbd 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,12 @@ +2020-04-04 Hannes Domani + Jakub Jelinek + + PR debug/94459 + * dwarf2out.c (gen_subprogram_die): Look through references, pointers, + arrays, pointer-to-members, function types and qualifiers when + checking if in-class DIE had an 'auto' or 'decltype(auto)' return type + to emit type again on definition. + 2020-04-04 Jan Hubicka PR ipa/93940 diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c index d68367eee3e..7d270f2a1b5 100644 --- a/gcc/dwarf2out.c +++ b/gcc/dwarf2out.c @@ -22905,11 +22905,22 @@ gen_subprogram_die (tree decl, dw_die_ref context_die) != (unsigned) s.column)) add_AT_unsigned (subr_die, DW_AT_decl_column, s.column); - /* If the prototype had an 'auto' or 'decltype(auto)' return type, - emit the real type on the definition die. */ + /* If the prototype had an 'auto' or 'decltype(auto)' in + the return type, emit the real type on the definition die. */ if (is_cxx () && debug_info_level > DINFO_LEVEL_TERSE) { dw_die_ref die = get_AT_ref (old_die, DW_AT_type); + while (die + && (die->die_tag == DW_TAG_reference_type + || die->die_tag == DW_TAG_rvalue_reference_type + || die->die_tag == DW_TAG_pointer_type + || die->die_tag == DW_TAG_const_type + || die->die_tag == DW_TAG_volatile_type + || die->die_tag == DW_TAG_restrict_type + || die->die_tag == DW_TAG_array_type + || die->die_tag == DW_TAG_ptr_to_member_type + || die->die_tag == DW_TAG_subroutine_type)) + die = get_AT_ref (die, DW_AT_type); if (die == auto_die || die == decltype_auto_die) add_type_attribute (subr_die, TREE_TYPE (TREE_TYPE (decl)), TYPE_UNQUALIFIED, false, context_die); diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 7b2d3c6edb1..058af2c3704 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2020-04-04 Hannes Domani + Jakub Jelinek + + PR debug/94459 + * g++.dg/debug/pr94459.C: New test. + 2020-04-04 Patrick Palka PR c++/94205 diff --git a/gcc/testsuite/g++.dg/debug/pr94459.C b/gcc/testsuite/g++.dg/debug/pr94459.C new file mode 100644 index 00000000000..ebc0cf45cc6 --- /dev/null +++ b/gcc/testsuite/g++.dg/debug/pr94459.C @@ -0,0 +1,58 @@ +// PR debug/94459 +// { dg-do compile { target c++14 } } +// { dg-options "-g -dA" } + +template +struct S +{ + T v; + T w[2]; + S () : v (0), w { 0, 0 } {} + static auto baz () { return (T) 0; } + auto m1 () { return v; } + auto &m2 () { return v; } + auto &&m3 () { return (T&&)v; } + const auto m4 () { return v; } + const auto &m5 () { return v; } + const auto &&m6 () { return (T&&)v; } + volatile auto m7 () { return v; } + volatile auto &m8 () { return v; } + volatile auto &&m9 () { return (T&&)v; } + volatile const auto m10 () { return v; } + volatile const auto &m11 () { return v; } + volatile const auto &&m12 () { return (T&&)v; } + const volatile auto m13 () { return v; } + const volatile auto &m14 () { return v; } + const volatile auto &&m15 () { return (T&&)v; } +#ifndef __STRICT_ANSI__ + __restrict const volatile auto &&m16 () { return (T&&)v; } + const __restrict auto &m17 () { return v; } +#endif + auto *m18 () { return &v; } + auto (S::* (m19 ())) () { return &S::m1; } + auto (S::* (m20 ())) { return &S::v; } + auto (*m21 ()) () { return S::baz; } +}; + +S s, u, v; + +long +foo () +{ + auto x = s.m19 (); + auto y = s.m20 (); + auto z = s.m21 (); + return s.m1 () + s.m2 () + s.m3 () + s.m4 () + s.m5 () + + s.m6 () + s.m7 () + s.m8 () + s.m9 () + s.m10 () + + s.m11 () + s.m12 () + s.m13 () + s.m14 () + s.m15 () +#ifndef __STRICT_ANSI__ + + u.m16 () + v.m17 () +#endif + + *s.m18 () + (s.*x) () + s.*y + z (); +} + +int +main () +{ + return foo (); +} -- 2.30.2