[Bug other/59622] [4.9 Regression] internal compiler error: verify_gimple failed

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59622

Jakub Jelinek jakub at gcc dot gnu.org changed:

   What|Removed |Added

 CC||jakub at gcc dot gnu.org

--- Comment #5 from Jakub Jelinek jakub at gcc dot gnu.org ---
  if (targets.length () == 1)
fndecl = targets[0]-decl;
  else
fndecl = builtin_decl_implicit (BUILT_IN_UNREACHABLE);
  gimple_call_set_fndecl (stmt, fndecl);
in gimple_fold_call is obviously wrong for the targets.length () == 0 case,
__builtin_unreachable () has no arguments, not the arguments of the call, and
no return value.
So, IMNSHO, for targets.length () == 0 you want to punt if inplace is true, and
otherwise not update the call itself, but replace the old call with a new stmt,
__builtin_unreachable ();, and if the call had a lhs with gimple_reg_type, add
lhs = 0 (build_zero_cst (TREE_TYPE (lhs))) after the __builtin_unreachable (),
so that it is defined, it will be hopefully DCEd soon afterwards but we
shouldn't let it being undefined, especially if it is e.g. anonymous SSA_NAME
which can't be undefined.

[Bug other/59622] [4.9 Regression] internal compiler error: verify_gimple failed

[glisse at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59622

Marc Glisse glisse at gcc dot gnu.org changed:

   What|Removed |Added

 Status|UNCONFIRMED |NEW
   Last reconfirmed||2013-12-29
   Target Milestone|--- |4.9.0
Summary|trunk gcc-4.9.0:internal|[4.9 Regression] internal
   |compiler error: |compiler error:
   |verify_gimple failed|verify_gimple failed
 Ever confirmed|0   |1

--- Comment #2 from Marc Glisse glisse at gcc dot gnu.org ---
Seems related to OBJ_TYPE_REF. -O2 is sufficient.

[Bug other/59622] [4.9 Regression] internal compiler error: verify_gimple failed

[trippels at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59622

Markus Trippelsdorf trippels at gcc dot gnu.org changed:

   What|Removed |Added

 CC||hubicka at ucw dot cz,
   ||trippels at gcc dot gnu.org

--- Comment #3 from Markus Trippelsdorf trippels at gcc dot gnu.org ---
Started with r206042.

[Bug other/59622] [4.9 Regression] internal compiler error: verify_gimple failed

[trippels at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59622

--- Comment #4 from Markus Trippelsdorf trippels at gcc dot gnu.org ---
Further reduced:

markus@x4 tmp % cat test.ii
namespace {
class A {
public:
  virtual int *m_fn1();
  int *m_fn2() { return m_fn1(); }
};
A a;
int b = *a.m_fn2();
}

markus@x4 tmp % g++ -O2 -c /var/tmp/test.ii
/var/tmp/test.ii: In member function ‘int* {anonymous}::A::m_fn2()’:
/var/tmp/test.ii:5:8: error: LHS in noreturn call
   int *m_fn2() { return m_fn1(); }
^
D.2269 = __builtin_unreachable (this);
/var/tmp/test.ii:5:8: internal compiler error: verify_gimple failed
0xb74c4f verify_gimple_in_seq(gimple_statement_base*)
../../gcc/gcc/tree-cfg.c:4521
0x99ffe1 gimplify_body(tree_node*, bool)
../../gcc/gcc/gimplify.c:8599
0x9a0399 gimplify_function_tree(tree_node*)
../../gcc/gcc/gimplify.c:8684
0x82eb97 analyze_function
../../gcc/gcc/cgraphunit.c:649
0x82fe4b analyze_functions
../../gcc/gcc/cgraphunit.c:1017
0x831475 finalize_compilation_unit()
../../gcc/gcc/cgraphunit.c:2271
0x62a57e cp_write_global_declarations()
../../gcc/gcc/cp/decl2.c:4431
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See http://gcc.gnu.org/bugs.html for instructions.

markus@x4 tmp % clang++ -c /var/tmp/test.ii
/var/tmp/test.ii:4:16: warning: function 'anonymous namespace::A::m_fn1' has
internal linkage but is not defined [-Wundefined-internal]
  virtual int *m_fn1();
   ^
/var/tmp/test.ii:5:25: note: used here
  int *m_fn2() { return m_fn1(); }
^
1 warning generated.
markus@x4 tmp %