On 1/21/21 2:44 PM, Marek Polacek wrote:
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;
We also want the warning if the version is less than 15 and the compat
version is 15 or greater. Ah, it seems write_member_name gets this
wrong, too. The abi_warn_or_compat_version_crosses check should not be
guarded by abi_version_at_least; all the other uses I'm seeing get this
right.
+ }
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
