On Tue, Jan 19, 2021 at 05:38:20PM -0500, Marek Polacek via Gcc-patches wrote: > On Tue, Jan 19, 2021 at 03:47:47PM -0500, Jason Merrill via Gcc-patches wrote: > > On 1/13/21 6:39 PM, Marek Polacek wrote: > > > r11-6301 added some asserts in mangle.c, and now we trip over one of > > > them. In particular, it's the one asserting that we didn't get > > > IDENTIFIER_ANY_OP_P when mangling an expression with a dependent name. > > > > > > As this testcase shows, it's possible to get that, so turn the assert > > > into an if and write "on". That changes the mangling in the following > > > way: > > > > > > With this patch: > > > > > > $ c++filt _ZN1i1hIJ1adS1_EEEDTcldtdefpTonclspcvT__EEEDpS2_ > > > decltype (((*this).(operator()))((a)(), (double)(), (a)())) i::h<a, > > > double, a>(a, double, a) > > > > > > G++10: > > > $ c++filt _ZN1i1hIJ1adS1_EEEDTcldtdefpTclspcvT__EEEDpS2_ > > > decltype (((*this).(operator()))((a)(), (double)(), (a)())) i::h<a, > > > double, a>(a, double, a) > > > > > > clang++/icc: > > > $ c++filt _ZN1i1hIJ1adS1_EEEDTclonclspcvT__EEEDpS2_ > > > decltype ((operator())((a)(), (double)(), (a)())) i::h<a, double, a>(a, > > > double, a) > > > > > > I'm not sure why we differ in the "(*this)." part > > > > Is there a PR for that? > > I just opened 98756, because I didn't find any. I can investigate where that > (*this) comes from, though it's not readily clear to me if this is a bug or > not. > > > > but at least the > > > suffix "onclspcvT__EEEDpS2_" is the same for all three compilers. So > > > I hope the following fix makes sense. > > > > > > Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? > > > > > > gcc/cp/ChangeLog: > > > > > > PR c++/98545 > > > * mangle.c (write_expression): When the expression is a dependent name > > > and an operator name, write "on" before writing its name. > > > > > > gcc/testsuite/ChangeLog: > > > > > > PR c++/98545 > > > * g++.dg/abi/mangle76.C: New test. > > > --- > > > gcc/cp/mangle.c | 3 ++- > > > gcc/testsuite/g++.dg/abi/mangle76.C | 39 +++++++++++++++++++++++++++++ > > > 2 files changed, 41 insertions(+), 1 deletion(-) > > > create mode 100644 gcc/testsuite/g++.dg/abi/mangle76.C > > > > > > diff --git a/gcc/cp/mangle.c b/gcc/cp/mangle.c > > > index 11eb8962d28..bb3c4b76d33 100644 > > > --- a/gcc/cp/mangle.c > > > +++ b/gcc/cp/mangle.c > > > @@ -3349,7 +3349,8 @@ write_expression (tree expr) > > > else if (dependent_name (expr)) > > > { > > > tree name = dependent_name (expr); > > > - gcc_assert (!IDENTIFIER_ANY_OP_P (name)); > > > + if (IDENTIFIER_ANY_OP_P (name)) > > > + write_string ("on"); > > > > Any mangling change needs to handle different -fabi-versions; see the > > similar code in write_member_name. > > Ah, I only looked at the unguarded IDENTIFIER_ANY_OP_P checks. But now > I have a possibly stupid question: what version should I check? We have > Version 11 for which the manual already says "corrects the mangling of > sizeof... expressions and *operator names*", so perhaps I could tag along > and check abi_version_at_least (11). Or should I check Version 15 and > update the manual?
The latter seems to be true, therefore a new patch is attached. > > And why doesn't this go through write_member_name? > > We go through write_member_name: > > #0 fancy_abort (file=0x2b98ef8 "/home/mpolacek/src/gcc/gcc/cp/mangle.c", > line=3352, > function=0x2b99751 "write_expression") at > /home/mpolacek/src/gcc/gcc/diagnostic.c:1884 > #1 0x0000000000bee91b in write_expression (expr=<overload 0x7fffea02eb20>) > at /home/mpolacek/src/gcc/gcc/cp/mangle.c:3352 > #2 0x0000000000beb3e2 in write_member_name (member=<baselink 0x7fffea043ae0>) > at /home/mpolacek/src/gcc/gcc/cp/mangle.c:2892 > #3 0x0000000000beee70 in write_expression (expr=<component_ref > 0x7fffea043b40>) > at /home/mpolacek/src/gcc/gcc/cp/mangle.c:3405 > #4 0x0000000000bef1be in write_expression (expr=<call_expr 0x7fffe9ede118>) > at /home/mpolacek/src/gcc/gcc/cp/mangle.c:3455 > #5 0x0000000000be858a in write_type (type=<decltype_type 0x7fffea04b348>) > at /home/mpolacek/src/gcc/gcc/cp/mangle.c:2343 > > so in write_member_name MEMBER is a BASELINK so we don't enter the > identifier_p block. Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? -- >8 -- r11-6301 added some asserts in mangle.c, and now we trip over one of them. In particular, it's the one asserting that we didn't get IDENTIFIER_ANY_OP_P when mangling an expression with a dependent name. As this testcase shows, it's possible to get that, so turn the assert into an if and write "on". That changes the mangling in the following way: With this patch: $ c++filt _ZN1i1hIJ1adS1_EEEDTcldtdefpTonclspcvT__EEEDpS2_ decltype (((*this).(operator()))((a)(), (double)(), (a)())) i::h<a, double, a>(a, double, a) G++10: $ c++filt _ZN1i1hIJ1adS1_EEEDTcldtdefpTclspcvT__EEEDpS2_ decltype (((*this).(operator()))((a)(), (double)(), (a)())) i::h<a, double, a>(a, double, a) clang++/icc: $ c++filt _ZN1i1hIJ1adS1_EEEDTclonclspcvT__EEEDpS2_ decltype ((operator())((a)(), (double)(), (a)())) i::h<a, double, a>(a, double, a) This is now tracked in PR98756. gcc/cp/ChangeLog: PR c++/98545 * mangle.c (write_expression): When the expression is a dependent name and an operator name, write "on" before writing its name. gcc/ChangeLog: PR c++/98545 * doc/invoke.texi: Update C++ ABI Version 15 description. gcc/testsuite/ChangeLog: PR c++/98545 * g++.dg/abi/mangle76.C: New test. --- gcc/cp/mangle.c | 7 ++++- gcc/doc/invoke.texi | 3 ++- gcc/testsuite/g++.dg/abi/mangle76.C | 40 +++++++++++++++++++++++++++++ 3 files changed, 48 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/g++.dg/abi/mangle76.C diff --git a/gcc/cp/mangle.c b/gcc/cp/mangle.c index 11eb8962d28..9b358bbc5a1 100644 --- a/gcc/cp/mangle.c +++ b/gcc/cp/mangle.c @@ -3349,7 +3349,12 @@ write_expression (tree expr) else if (dependent_name (expr)) { tree name = dependent_name (expr); - gcc_assert (!IDENTIFIER_ANY_OP_P (name)); + if (abi_version_at_least (15) && IDENTIFIER_ANY_OP_P (name)) + { + write_string ("on"); + if (abi_warn_or_compat_version_crosses (15)) + G.need_abi_warning = 1; + } write_unqualified_id (name); } else diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 5f4a06625eb..99d25462e48 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -2837,7 +2837,8 @@ Version 14, which first appeared in G++ 10, corrects the mangling of the nullptr expression. Version 15, which first appeared in G++ 11, changes the mangling of -@code{__alignof__} to be distinct from that of @code{alignof}. +@code{__alignof__} to be distinct from that of @code{alignof}, and +dependent operator names. See also @option{-Wabi}. diff --git a/gcc/testsuite/g++.dg/abi/mangle76.C b/gcc/testsuite/g++.dg/abi/mangle76.C new file mode 100644 index 00000000000..fe326e6c689 --- /dev/null +++ b/gcc/testsuite/g++.dg/abi/mangle76.C @@ -0,0 +1,40 @@ +// PR c++/98545 +// { dg-do compile { target c++11 } } +// { dg-options "-Wabi=14" } + +class a { +public: + a(); + template <typename b> a(b); +}; +template <class = double> using c = a; +class f { +protected: + template <class d, class e> void operator()(d, double, e); +}; +class i : f { +public: + template <class... g> + [[gnu::used]] auto h(g...) -> decltype(operator()(g()...)) {} // { dg-warning "mangled name" } +// { dg-final { scan-assembler "_ZN1i1hIJ1adS1_EEEDTcldtdefpTonclspcvT__EEEDpS2_" } } +}; +template <class> class C { +public: + template <class j> C(j); + i k() const; + int operator()() { + int l = 10; + c<> m, n; + operator()(m, l, n); + return 0; + } + int operator()(c<> &, c<> const &, c<> const &) const; + template <class d, class e> void k(d m, double gamma, e o) const { + k().h(m, gamma, o); + } +}; +template <class r> int C<r>::operator()(c<> &, c<> const &, c<> const &) const { + [&](c<> m, double gamma, c<> o) { k(m, gamma, o); }; + return 0; +} +c<> p = C<double>(p)(); base-commit: 0fb7aa205afebe178c06683037ccd4c41104337a -- 2.29.2