[Bug tree-optimization/109806] [13/14 Regression] 13.1.0 cc1plus stack smashing crash with C array of complex structs

["sjames at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109806

Sam James <sjames at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |aldyh at gcc dot gnu.org
           See Also|                            |https://bugs.gentoo.org/sho
                   |                            |w_bug.cgi?id=906380

--- Comment #12 from Sam James <sjames at gcc dot gnu.org> ---
I think I'm hitting this on musl too. Reported in Gentoo at
https://bugs.gentoo.org/906380.

For me, this crashes on x86_64-gentoo-linux-musl:
```
struct SimpleRefCounted {
  virtual void addRef();
};
struct timespec {
  long tv_nsec;
  int : 0;
};
struct ClockImpl : SimpleRefCounted {
  timespec _startTime;
};
struct Clock {
  Clock();
};
Clock::Clock() { ClockImpl(); }
```

with:
```
# g++ /tmp/foo.cxx -O2 -wrapper valgrind
==1239523== Memcheck, a memory error detector
==1239523== Copyright (C) 2002-2022, and GNU GPL'd, by Julian Seward et al.
==1239523== Using Valgrind-3.21.0 and LibVEX; rerun with -h for copyright info
==1239523== Command: /usr/libexec/gcc/x86_64-gentoo-linux-musl/13/cc1plus
-quiet -D_GNU_SOURCE /tmp/foo.cxx -quiet -dumpdir a- -dumpbase foo.cxx
-dumpbase-ext .cxx -mtune=generic -march=x86-64 -O2 -fcf-protection -o
/tmp/ccigHfiN.s
==1239523==
==1239523== Invalid read of size 1
==1239523==    at 0x97844C: to_wide (tree.h:6257)
==1239523==    by 0x97844C: irange::set_varying(tree_node*) (value-range.h:959)
==1239523==    by 0x10C1A45: range_query::get_tree_range(vrange&, tree_node*,
gimple*) (value-query.cc:252)
==1239523==    by 0x1B52256: gimple_ranger::range_of_stmt(vrange&, gimple*,
tree_node*) (gimple-range.cc:298)
==1239523==    by 0x1B52778: gimple_ranger::register_inferred_ranges(gimple*)
(gimple-range.cc:474)
==1239523==    by 0x109FB19: rvrp_folder::fold_stmt(gimple_stmt_iterator*)
(tree-vrp.cc:1079)
==1239523==    by 0xFA9ED3:
substitute_and_fold_dom_walker::before_dom_children(basic_block_def*)
(tree-ssa-propagate.cc:848)
==1239523==    by 0x1B24C2E: dom_walker::walk(basic_block_def*)
(domwalk.cc:311)
==1239523==    by 0xFA9312:
substitute_and_fold_engine::substitute_and_fold(basic_block_def*)
(tree-ssa-propagate.cc:971)
==1239523==    by 0x109DB80: execute_ranger_vrp(function*, bool, bool)
(tree-vrp.cc:1107)
==1239523==    by 0xD3A0EA: execute_one_pass(opt_pass*) (passes.cc:2651)
==1239523==    by 0xD3A9AF: execute_pass_list_1(opt_pass*) (passes.cc:2760)
==1239523==    by 0xD3A9C1: execute_pass_list_1(opt_pass*) (passes.cc:2761)
==1239523==  Address 0x4 is not stack'd, malloc'd or (recently) free'd
==1239523==
during GIMPLE pass: evrp
/tmp/foo.cxx: In constructor 'Clock::Clock()':
/tmp/foo.cxx:14:31: internal compiler error: Segmentation fault
   14 | Clock::Clock() { ClockImpl(); }
      |                               ^

0xe10df3 crash_signal
       
/usr/src/debug/sys-devel/gcc-13.1.1_p20230513/gcc-13-20230513/gcc/toplev.cc:314
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://bugs.gentoo.org/> for instructions.
```

(Obviously crashes w/o valgrind too, just the output is way less helpful.)

Note that musl has a small default stack size, as I mentioned at
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109695#c18.