[Bug ipa/94856] New: [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration)

[Bug ipa/94856] New: [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration)

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

            Bug ID: 94856
           Summary: [10 Regression] ICE: Segmentation fault (in
                    clone_of_p); or ICE: verify_cgraph_node failed (error:
                    edge points to wrong declaration)
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: ipa
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
                CC: marxin at gcc dot gnu.org
  Target Milestone: ---

1.

g++-10.0.1-alpha20200426 snapshot (g:29f55115583a0dab6cbac749c4f0804fd88e9536)
ICEs when compiling gcc/testsuite/g++.dg/other/pr47218.C w/ -O2 -fgnu-tm
-fopenacc -fno-tree-dse --param early-inlining-insns=3 --param
uninlined-function-insns=0:

% g++-10.0.1 -O2 -fgnu-tm -fopenacc -fno-tree-dse --param
early-inlining-insns=3 --param uninlined-function-insns=0 -c
gcc/testsuite/g++.dg/other/pr47218.C
during IPA pass: inline
gcc/testsuite/g++.dg/other/pr47218.C: In destructor 'virtual Foo3::~Foo3()':
gcc/testsuite/g++.dg/other/pr47218.C:10:1: internal compiler error:
Segmentation fault
   10 | }
      | ^
0xfebacf crash_signal
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/toplev.c:328
0xb85dd9 clone_of_p
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraph.c:3108
0xb85dd9 cgraph_edge::verify_corresponds_to_fndecl(tree_node*)
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraph.c:3196
0xb8d780 cgraph_node::verify_node()
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraph.c:3719
0xb7fcf4 symtab_node::verify()
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/symtab.c:1312
0x1074525 expand_call_inline
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/tree-inline.c:4820
0x1076ee9 gimple_expand_calls_inline
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/tree-inline.c:5251
0x1076ee9 optimize_inline_calls(tree_node*)
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/tree-inline.c:5424
0xddbef3 inline_transform(cgraph_node*)
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/ipa-inline-transform.c:734
0xf182dd execute_one_ipa_transform_pass
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/passes.c:2233
0xf182dd execute_all_ipa_transforms(bool)
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/passes.c:2272
0xb86644 cgraph_node::get_body()
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraph.c:3970
0x11df6f1 ipa_pta_execute
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/tree-ssa-structalias.c:8140
0x11df6f1 execute
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/tree-ssa-structalias.c:8557

2.

Omission of -fopenacc from the command line yields the following instead:

% g++-10.0.1 -O2 -fgnu-tm -fno-tree-dse --param early-inlining-insns=3 --param
uninlined-function-insns=0 -c gcc/testsuite/g++.dg/other/pr47218.C
gcc/testsuite/g++.dg/other/pr47218.C: In destructor 'Foo3::~Foo3()':
gcc/testsuite/g++.dg/other/pr47218.C:7:1: error: edge points to wrong
declaration:
    7 | Foo3::~Foo3 ()
      | ^~~~
 <function_decl 0x7f811058c600 Bar.constprop
    type <function_type 0x7f81105887e0
        type <void_type 0x7f8110400f18 void VOID
            align:8 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7f8110400f18
            pointer_to_this <pointer_type 0x7f8110408000>>
        QI
        size <integer_cst 0x7f81103e2f60 constant 8>
        unit-size <integer_cst 0x7f81103e2f78 constant 1>
        align:8 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7f81105887e0
        arg-types <tree_list 0x7f81103f6910 value <void_type 0x7f8110400f18
void>>>
    readonly addressable asm_written used nothrow static decl_5 QI
gcc/testsuite/g++.dg/other/pr47218.C:12:6 align:16 warn_if_not_align:0 context
<record_type 0x7f81105702a0 Foo3> initial <error_mark 0x7f81103e2e58>
abstract_origin <function_decl 0x7f8110572100 Bar>
    (mem:QI (symbol_ref:DI ("_ZN4Foo33BarEv.constprop.0") [flags 0x3]
<function_decl 0x7f811058c600 Bar.constprop>) [0  S1 A8])>
 Instead of: <function_decl 0x7f8110572500 _ZThn8_N4Foo33BarEv
    type <method_type 0x7f8110570690
        type <void_type 0x7f8110400f18 void VOID
            align:8 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7f8110400f18
            pointer_to_this <pointer_type 0x7f8110408000>>
        QI
        size <integer_cst 0x7f81103e2f60 constant 8>
        unit-size <integer_cst 0x7f81103e2f78 constant 1>
        align:8 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7f8110570690 method basetype <record_type 0x7f81105702a0 Foo3>
        arg-types <tree_list 0x7f8110571050 value <pointer_type 0x7f8110570930>
            chain <tree_list 0x7f81103f6910 value <void_type 0x7f8110400f18
void>>>
        pointer_to_this <pointer_type 0x7f8110573738>>
    readonly addressable used nothrow public ignored virtual decl_5 QI
gcc/testsuite/g++.dg/other/pr47218.h:32:16 align:8 warn_if_not_align:0 context
<record_type 0x7f81105702a0 Foo3> initial <block 0x7f811057e6c0>
    result <result_decl 0x7f8110566ca8 D.2615 type <void_type 0x7f8110400f18
void>
        ignored VOID gcc/testsuite/g++.dg/other/pr47218.C:19:1
        align:8 warn_if_not_align:0 context <function_decl 0x7f8110572500
_ZThn8_N4Foo33BarEv>>
    full-name "virtual void Foo3::_ZThn8_N4Foo33BarEv()"

    arguments <parm_decl 0x7f8110575580 this
        type <pointer_type 0x7f8110570a80 type <record_type 0x7f81105702a0
Foo3>
            readonly public unsigned DI
            size <integer_cst 0x7f81103e2e70 constant 64>
            unit-size <integer_cst 0x7f81103e2e88 constant 8>
            align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7f8110570a80>
        readonly unsigned read DI gcc/testsuite/g++.dg/other/pr47218.C:12:16
size <integer_cst 0x7f81103e2e70 64> unit-size <integer_cst 0x7f81103e2e88 8>
        align:64 warn_if_not_align:0 context <function_decl 0x7f8110572500
_ZThn8_N4Foo33BarEv> arg-type <pointer_type 0x7f8110570a80>>
    struct-function 0x7f8110561bb0>
_ZN4Foo3D2Ev/44 (Foo3::~Foo3()) @0x7f81105a09d8
  Type: function definition analyzed
  Visibility: artificial
  next sharing asm name: 13
  References: _ZTV4Foo3/20 (addr) _ZTV4Foo3/20 (addr) _ZTV7FooBase/21 (addr)
_ZTV7FooBase/21 (addr) _ZTV12FooBaseBase0/23 (addr) __gxx_personality_v0/32
(addr) 
  Referring: 
  Function Foo3::~Foo3()/44 is inline copy in virtual Foo3::~Foo3()/15
  Availability: local
  Function flags: count:1073741824 (estimated locally) body local nonfreeing_fn
  Called by: _ZN4Foo3D0Ev/15 (inlined) (1073741824 (estimated locally),1.00 per
call) 
  Calls: _ZN4Foo33BarEv.constprop.0/41 (1073741824 (estimated locally),1.00 per
call) 
during IPA pass: inline
gcc/testsuite/g++.dg/other/pr47218.C:7:1: internal compiler error:
verify_cgraph_node failed
0xb8d09e cgraph_node::verify_node()
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraph.c:3810
0xb7fcf4 symtab_node::verify()
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/symtab.c:1312
0xddbf27 save_inline_function_body
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/ipa-inline-transform.c:658
0xddbf27 inline_transform(cgraph_node*)
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/ipa-inline-transform.c:695
0xf182dd execute_one_ipa_transform_pass
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/passes.c:2233
0xf182dd execute_all_ipa_transforms(bool)
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/passes.c:2272
0xb92b63 cgraph_node::expand()
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraphunit.c:2293
0xb93db6 expand_all_functions
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraphunit.c:2471
0xb93db6 symbol_table::compile()
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraphunit.c:2822
0xb9612c symbol_table::compile()
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraphunit.c:2735
0xb9612c symbol_table::finalize_compilation_unit()
       
/var/tmp/portage/sys-devel/gcc-10.0.1_alpha20200426/work/gcc-10-20200426/gcc/cgraphunit.c:3002

[Bug ipa/94856] [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |9.3.0
            Summary|[10 Regression] ICE:        |[10 Regression] ICE:
                   |Segmentation fault (in      |Segmentation fault (in
                   |clone_of_p); or ICE:        |clone_of_p); or ICE:
                   |verify_cgraph_node failed   |verify_cgraph_node failed
                   |(error: edge points to      |(error: edge points to
                   |wrong declaration)          |wrong declaration) since
                   |                            |r10-4944-g1e83bd7003e03160
   Last reconfirmed|                            |2020-4-29
                 CC|                            |hubicka at gcc dot gnu.org
      Known to fail|                            |10.0
   Target Milestone|---                         |10.0

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
Started with r10-4944-g1e83bd7003e03160.

[Bug ipa/94856] [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
                 CC|                            |jamborm at gcc dot gnu.org
             Status|UNCONFIRMED                 |NEW

--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> ---
I can take a look tomorrow.

[Bug ipa/94856] [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
The issue was likely latent before the cited rev. - for this reason and because
the testcase needs -fgnu-tm which is not maintained _not_ P1.

[Bug ipa/94856] [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
Reduced test-case:

class a {
public:
  virtual ~a() {}
};
class b {
public:
  virtual void c();
};
class C : a, public b {};
class d : C {
  ~d();
  void c();
};
d::~d() { ((b *)this)->c(); }
void d::c() {}

[Bug ipa/94856] [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
So the GNU TM is involved only very slightly as it prevents one inlining
candidate:

Without -fgnu-tm:

Enqueueing calls in d::~d()/9.
   Estimating body: c.constprop/34
   Known to be false: not inlined
   size:0 time:0.000000 nonspec time:2.000000
   Estimating body: c.constprop/34
   Known to be false: not inlined
   size:0 time:0.000000 nonspec time:2.000000
  enqueuing call d::~d()/9 -> c.constprop/34, badness -inf

With -fgnu-tm:
pr47218.ii:14:25: missed:   not inlinable: d::~d()/9 -> c.constprop/34,

reason is this:
ipa-inline.c:364:

  /* TM pure functions should not be inlined into non-TM_pure
     functions.  */
  else if (is_tm_pure (callee->decl) && !is_tm_pure (caller->decl))
    {
      e->inline_failed = CIF_UNSPECIFIED;
      inlinable = false;
    }

The following patch can cause the ICE without -fgnu-tm:

diff --git a/gcc/ipa-inline.c b/gcc/ipa-inline.c
index f71443feff7..cb968059a28 100644
--- a/gcc/ipa-inline.c
+++ b/gcc/ipa-inline.c
@@ -361,7 +361,8 @@ can_inline_edge_p (struct cgraph_edge *e, bool report,
     }
   /* TM pure functions should not be inlined into non-TM_pure
      functions.  */
-  else if (is_tm_pure (callee->decl) && !is_tm_pure (caller->decl))
+  else if (strcmp (callee->name(), "c.constprop") == 0
+          && strcmp (caller->name(), "d::~d()") == 0)
     {
       e->inline_failed = CIF_UNSPECIFIED;
       inlinable = false;

@Martin, Honza: Can you please take a look?
I tend to mark it as P1.

[Bug ipa/94856] [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

--- Comment #6 from Martin Liška <marxin at gcc dot gnu.org> ---
With the patch, minimal options are:
g++ pr47218.ii -fno-tree-dse --param uninlined-function-insns=0 --param
early-inlining-insns=3 -O2 -c

[Bug ipa/94856] [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[jamborm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

--- Comment #7 from Martin Jambor <jamborm at gcc dot gnu.org> ---
The "edge points to wrong decl" case is a verifier error.  We have a
method which (in the course of IPA-CP) loses its this pointer because
it is unused and the pass then does not clone all the this adjusting
thunks and just makes the calls go straight to the new clone - and
then the verifier complains that the edge does not seem to point to a
clone of what it used to.  This looked weird because the verifier
actually has logic detecting this case but it turns out that it is
confused by inliner body-saving mechanism which invents a new decl for
the base function.

Inlining body-saving mechanism should correctly set former_clone_of
and then we can detect this case too.  Then we pass this particular
round of verification but the subsequent one fails because we have
inlined the function into its former thunk - which subsequently does
not have any callees, but the verifier still access them and segfaults
just like in the original -fopenacc case.  That is why the following
(yet untested) patch most likely fixes that case too:

diff --git a/gcc/cgraph.c b/gcc/cgraph.c
index 72d7cb54301..2a9813df2d9 100644
--- a/gcc/cgraph.c
+++ b/gcc/cgraph.c
@@ -3104,15 +3104,17 @@ clone_of_p (cgraph_node *node, cgraph_node *node2)
        return false;
       /* In case of instrumented expanded thunks, which can have multiple
calls
         in them, we do not know how to continue and just have to be
-        optimistic.  */
-      if (node->callees->next_callee)
+        optimistic.  The same applies if all calls have already been inlined
+        into the thunk.  */
+      if (!node->callees || node->callees->next_callee)
        return true;
       node = node->callees->callee->ultimate_alias_target ();

       if (!node2->clone.param_adjustments
          || node2->clone.param_adjustments->first_param_intact_p ())
        return false;
-      if (node2->former_clone_of == node->decl)
+      if (node2->former_clone_of == node->decl
+         || node2->former_clone_of == node->former_clone_of)
        return true;

       cgraph_node *n2 = node2;
diff --git a/gcc/ipa-inline-transform.c b/gcc/ipa-inline-transform.c
index be60bbccb5c..e9e21cc0296 100644
--- a/gcc/ipa-inline-transform.c
+++ b/gcc/ipa-inline-transform.c
@@ -607,6 +607,8 @@ save_inline_function_body (struct cgraph_node *node)
        }
     }
   *ipa_saved_clone_sources->get_create (first_clone) = prev_body_holder;
+  first_clone->former_clone_of
+    = node->former_clone_of ? node->former_clone_of : node->decl;
   first_clone->clone_of = NULL;

   /* Now node in question has no clones.  */

[Bug ipa/94856] [10 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[jamborm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

--- Comment #8 from Martin Jambor <jamborm at gcc dot gnu.org> ---
I proposed the patch on the mailing list:
https://gcc.gnu.org/pipermail/gcc-patches/2020-April/544943.html

[Bug ipa/94856] [10/11 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Martin Jambor <jamborm@gcc.gnu.org>:

https://gcc.gnu.org/g:b31ede6e376302047830691fe6249be3ade0a2c0

commit r11-1-gb31ede6e376302047830691fe6249be3ade0a2c0
Author: Martin Jambor <mjambor@suse.cz>
Date:   Thu Apr 30 17:59:00 2020 +0200

    ipa: Cgraph verification fix (PR 94856)

    PR 94856 is a call graph verifier error.  We have a method which (in
    the course of IPA-CP) loses its this pointer because it is unused and
    the pass then does not clone all the this adjusting thunks and just
    makes the calls go straight to the new clone - and then the verifier
    complains that the edge does not seem to point to a clone of what it
    used to.  This looked weird because the verifier actually has logic
    detecting this case but it turns out that it is confused by inliner
    body-saving mechanism which invents a new decl for the base function.

    Making the inlining body-saving mechanism to correctly set
    former_clone_of allows us to detect this case too.  Then we pass this
    particular round of verification but the subsequent one fails because
    we have inlined the function into its former thunk - which
    subsequently does not have any callees, but the verifier still access
    them and segfaults.  Therefore the patch also adds a test whether the
    a former hunk even has any call.

    2020-04-30  Martin Jambor  <mjambor@suse.cz>

            PR ipa/94856
            * cgraph.c (clone_of_p): Also consider thunks whih had their bodies
            saved by the inliner and thunks which had their call inlined.
            * ipa-inline-transform.c (save_inline_function_body): Fill in
            former_clone_of of new body holders.

            PR ipa/94856
            * g++.dg/ipa/pr94856.C: New test.

[Bug ipa/94856] [10/11 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

--- Comment #10 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-10 branch has been updated by Martin Jambor
<jamborm@gcc.gnu.org>:

https://gcc.gnu.org/g:e72cfef362a98528bf3d199f127916c3dbef7727

commit r10-8079-ge72cfef362a98528bf3d199f127916c3dbef7727
Author: Martin Jambor <mjambor@suse.cz>
Date:   Thu Apr 30 17:59:00 2020 +0200

    ipa: Cgraph verification fix (PR 94856)

    PR 94856 is a call graph verifier error.  We have a method which (in
    the course of IPA-CP) loses its this pointer because it is unused and
    the pass then does not clone all the this adjusting thunks and just
    makes the calls go straight to the new clone - and then the verifier
    complains that the edge does not seem to point to a clone of what it
    used to.  This looked weird because the verifier actually has logic
    detecting this case but it turns out that it is confused by inliner
    body-saving mechanism which invents a new decl for the base function.

    Making the inlining body-saving mechanism to correctly set
    former_clone_of allows us to detect this case too.  Then we pass this
    particular round of verification but the subsequent one fails because
    we have inlined the function into its former thunk - which
    subsequently does not have any callees, but the verifier still access
    them and segfaults.  Therefore the patch also adds a test whether the
    a former hunk even has any call.

    2020-04-30  Martin Jambor  <mjambor@suse.cz>

            PR ipa/94856
            * cgraph.c (clone_of_p): Also consider thunks whih had their bodies
            saved by the inliner and thunks which had their call inlined.
            * ipa-inline-transform.c (save_inline_function_body): Fill in
            former_clone_of of new body holders.

            PR ipa/94856
            * g++.dg/ipa/pr94856.C: New test.

[Bug ipa/94856] [10/11 Regression] ICE: Segmentation fault (in clone_of_p); or ICE: verify_cgraph_node failed (error: edge points to wrong declaration) since r10-4944-g1e83bd7003e03160

[jamborm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94856

Martin Jambor <jamborm at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|NEW                         |RESOLVED

--- Comment #11 from Martin Jambor <jamborm at gcc dot gnu.org> ---
Fixed on both master and the newly created gcc-10 branch.