* [Bug ipa/108702] [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 since r13-4161-g32d16fe9d7e347bc
2023-02-07 18:36 [Bug ipa/108702] New: [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 asolokha at gmx dot com
@ 2023-02-08 14:27 ` marxin at gcc dot gnu.org
2023-02-08 16:08 ` jakub at gcc dot gnu.org
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: marxin at gcc dot gnu.org @ 2023-02-08 14:27 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108702
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|[13 Regression] ICE in |[13 Regression] ICE in
|get_partitioning_class, at |get_partitioning_class, at
|symtab.cc:2096 |symtab.cc:2096 since
| |r13-4161-g32d16fe9d7e347bc
Last reconfirmed| |2023-02-08
Status|UNCONFIRMED |NEW
Ever confirmed|0 |1
CC| |jakub at gcc dot gnu.org
--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
Started with r13-4161-g32d16fe9d7e347bc.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug ipa/108702] [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 since r13-4161-g32d16fe9d7e347bc
2023-02-07 18:36 [Bug ipa/108702] New: [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 asolokha at gmx dot com
2023-02-08 14:27 ` [Bug ipa/108702] [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 since r13-4161-g32d16fe9d7e347bc marxin at gcc dot gnu.org
@ 2023-02-08 16:08 ` jakub at gcc dot gnu.org
2023-02-08 17:27 ` [Bug c++/108702] " jakub at gcc dot gnu.org
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: jakub at gcc dot gnu.org @ 2023-02-08 16:08 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108702
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Without -flto, the testcase can't be linked:
./cc1plus -quiet -std=c++23 stmtexpr19.C; g++ -o stmtexpr19{,.s}
/usr/bin/ld: /tmp/ccUo7FRx.o:(.rodata+0x0): undefined reference to
`setup()::inner'
collect2: error: ld returned 1 exit status
On the other side, when static constexpr vars are defined inside of constexpr
functions or even consteval functions, it works ok:
extern "C" void abort ();
constexpr const int *
foo ()
{
static constexpr int a = 1;
return &a;
}
consteval const int *
bar ()
{
static constexpr int a = 1;
return &a;
}
[[gnu::noipa]] void
baz (const int *x)
{
if (*x != 1)
abort ();
}
int
main ()
{
constexpr const int *p = foo ();
constexpr const int *q = bar ();
baz (p);
baz (q);
if (p == q)
abort ();
}
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug c++/108702] [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 since r13-4161-g32d16fe9d7e347bc
2023-02-07 18:36 [Bug ipa/108702] New: [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 asolokha at gmx dot com
2023-02-08 14:27 ` [Bug ipa/108702] [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 since r13-4161-g32d16fe9d7e347bc marxin at gcc dot gnu.org
2023-02-08 16:08 ` jakub at gcc dot gnu.org
@ 2023-02-08 17:27 ` jakub at gcc dot gnu.org
2023-03-04 8:55 ` cvs-commit at gcc dot gnu.org
2023-03-04 9:24 ` jakub at gcc dot gnu.org
4 siblings, 0 replies; 6+ messages in thread
From: jakub at gcc dot gnu.org @ 2023-02-08 17:27 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108702
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Component|ipa |c++
Priority|P3 |P1
CC| |jason at gcc dot gnu.org
Target Milestone|--- |13.0
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Seems the reason why the above testcase works and stmtexpr19.C doesn't is in
make_rtl_for_nonlocal_decl's
7732 /* We defer emission of local statics until the corresponding
7733 DECL_EXPR is expanded. But with constexpr its function might
never
7734 be expanded, so go ahead and tell cgraph about the variable now.
*/
7735 defer_p = ((DECL_FUNCTION_SCOPE_P (decl)
7736 && !var_in_maybe_constexpr_fn (decl))
7737 || DECL_VIRTUAL_P (decl));
while in stmtexpr19.C the inner decl isn't in constexpr fn, it is in a
statement expression inside of a static variable initializer.
The initializer evaluates to constant expression (ADDR_EXPR of inner), so the
statement expression disappears and so there is no DECL_EXPR for the inner var
nor any reasonable spot to stick it to.
I think the options are somehow discover these before they are folded away and
mark them some way, so that we don't defer_p them or otherwise arrange for
rest_of_decl_compilation to be done on them later, or, as statement expressions
are a GNU extension, simply declare that such variables in statement
expressions cause it to be not a constant expression, only DECL_EXPRs of
var_in_maybe_constexpr_fn (decl) would be accepted.
Or, do we ever need to defer_p the static variables we are talking about here
(i.e. constexpr ones or ones with constant initializers, for which it really
doesn't matter where exactly we initialize them because they are initialized in
.rodata already.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug c++/108702] [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 since r13-4161-g32d16fe9d7e347bc
2023-02-07 18:36 [Bug ipa/108702] New: [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 asolokha at gmx dot com
` (2 preceding siblings ...)
2023-02-08 17:27 ` [Bug c++/108702] " jakub at gcc dot gnu.org
@ 2023-03-04 8:55 ` cvs-commit at gcc dot gnu.org
2023-03-04 9:24 ` jakub at gcc dot gnu.org
4 siblings, 0 replies; 6+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2023-03-04 8:55 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108702
--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:
https://gcc.gnu.org/g:9d5730dee4f42e94004b38f8f4862c0b1f4d964c
commit r13-6473-g9d5730dee4f42e94004b38f8f4862c0b1f4d964c
Author: Jakub Jelinek <jakub@redhat.com>
Date: Sat Mar 4 09:51:31 2023 +0100
c++: Don't defer local statics initialized with constant expressions
[PR108702]
The stmtexpr19.C testcase used to be rejected as it has a static
variable in statement expression in constexpr context, but as that
static variable is initialized by constant expression, when P2647R1
was implemented we agreed to make it valid.
Now, as reported, the testcase compiles fine, but doesn't actually link
because the static variable isn't defined anywhere, and with -flto ICEs
because of this problem. This is because we never
varpool_node::finalize_decl those vars, the constant expression in which
the DECL_EXPR is present for the static VAR_DECL is folded (constant
evaluated) into just the address of the VAR_DECL.
Now, similar testcase included below (do we want to include it in the
testsuite too?) works fine, because in
cp_finish_decl -> make_rtl_for_nonlocal_decl
we have since PR70353 fix:
/* We defer emission of local statics until the corresponding
DECL_EXPR is expanded. But with constexpr its function might never
be expanded, so go ahead and tell cgraph about the variable now. */
defer_p = ((DECL_FUNCTION_SCOPE_P (decl)
&& !var_in_maybe_constexpr_fn (decl))
|| DECL_VIRTUAL_P (decl));
and so don't defer them in constexpr/consteval functions. The following
patch calls rest_of_decl_compilation which make_rtl_for_nonlocal_decl
didn't
call when encountering DECL_EXPRs of such vars during constant evaluation
if they weren't finalized yet.
2023-03-04 Jakub Jelinek <jakub@redhat.com>
PR c++/108702
* constexpr.cc: Include toplev.h.
(cxx_eval_constant_expression) <case DECL_EXPR>: When seeing a
local
static initialized by constant expression outside of a constexpr
function which has been deferred by make_rtl_for_nonlocal_decl,
call rest_of_decl_compilation on it.
* g++.dg/ext/stmtexpr19.C: Use dg-do link rather than dg-do
compile.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug c++/108702] [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 since r13-4161-g32d16fe9d7e347bc
2023-02-07 18:36 [Bug ipa/108702] New: [13 Regression] ICE in get_partitioning_class, at symtab.cc:2096 asolokha at gmx dot com
` (3 preceding siblings ...)
2023-03-04 8:55 ` cvs-commit at gcc dot gnu.org
@ 2023-03-04 9:24 ` jakub at gcc dot gnu.org
4 siblings, 0 replies; 6+ messages in thread
From: jakub at gcc dot gnu.org @ 2023-03-04 9:24 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108702
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Assignee|unassigned at gcc dot gnu.org |jakub at gcc dot gnu.org
Status|NEW |RESOLVED
Resolution|--- |FIXED
--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed.
^ permalink raw reply [flat|nested] 6+ messages in thread