LTA: giving Proc's :err wrongly-opened handle fails silently

[zoffixznet]

Don't know if it's some quirk of the system/shell, but feels buggy:

Here, we open the handle in read mode and give it to Proc's :out/:err.

When given to :out, we get an error about failed write, but if we give the same handle to :err, we get silence:

$ ./perl6 -e 'with $*TMPDIR.add("meows") { .open(:w).close; my $ = run «perl6 -e "note 42"», :err(.open) }'

$ ./perl6 -e 'with $*TMPDIR.add("meows") { .open(:w).close; my $ = run «perl6 -e "say 42"», :out(.open) }'
Failed to write bytes to filehandle: Bad file descriptor
  in block <unit> at -e line 1

$ ./perl6 -v
This is Rakudo version 2018.06-404-g0b3fc07 built on MoarVM version 2018.06-399-g4fc267b
implementing Perl 6.c.

[schaiba]

Still seeing this with 2020.12 . And I get the same error with the following :
my $maxint = (2**31) - 1; say "H" x $maxint; when using the REPL.

[MasterDuke17]

I can repro, I get the error Failed to write bytes to filehandle: Bad address in block <unit> at -e line 1

[dan@alexandria perl6]$ gdb --args ./install/bin/raku -e 'say "H" x 2147483647;'
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Reading symbols from ./install/bin/raku...
(gdb) b MVM_exception_throw_adhoc
Function "MVM_exception_throw_adhoc" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (MVM_exception_throw_adhoc) pending.
(gdb) r
Starting program: /home/dan/Source/perl6/install/bin/raku -e say\ \"H\"\ x\ 2147483647\;
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
[New Thread 0x7ffff6de3640 (LWP 364039)]

Thread 1 "raku" hit Breakpoint 1, MVM_exception_throw_adhoc (tc=tc@entry=0x55555555a0d0, messageFormat=messageFormat@entry=0x7ffff7a03b80 "Failed to write bytes to filehandle: %s") at src/core/exceptions.c:895
895     MVM_NO_RETURN void MVM_exception_throw_adhoc(MVMThreadContext *tc, const char *messageFormat, ...) {
(gdb) bt
#0  MVM_exception_throw_adhoc (tc=tc@entry=0x55555555a0d0, messageFormat=messageFormat@entry=0x7ffff7a03b80 "Failed to write bytes to filehandle: %s") at src/core/exceptions.c:895
#1  0x00007ffff78dca2e in perform_write (data=0x5555555efd30, buf=0x7ffeebfff010 'H' <repeats 200 times>..., bytes=<optimized out>, tc=0x55555555a0d0) at src/io/syncfile.c:82
#2  perform_write (tc=0x55555555a0d0, data=0x5555555efd30, buf=0x7ffeebfff010 'H' <repeats 200 times>..., bytes=<optimized out>) at src/io/syncfile.c:71
#3  0x00007ffff78dca61 in write_bytes (tc=<optimized out>, h=<optimized out>, buf=0x7ffeebfff010 'H' <repeats 200 times>..., bytes=2147483648) at src/io/syncfile.c:219
#4  0x00007ffff78da399 in MVM_io_write_bytes (tc=0x55555555a0d0, oshandle=<optimized out>, buffer=<optimized out>) at src/io/io.c:158
#5  0x00007ffff7890c3b in MVM_interp_run (tc=0x55555555a0d0, initial_invoke=0x7ffff7a03b80, initial_invoke@entry=0x7ffff79a0e40 <toplevel_initial_invoke>, invoke_data=0x7ffff7a03b80, 
    invoke_data@entry=0x7ffff79a0e40 <toplevel_initial_invoke>, outer_runloop=0xffffffffffffff90, outer_runloop@entry=0x0) at src/core/interp.c:3949
#6  0x00007ffff79a1fa4 in MVM_vm_run_file (instance=instance@entry=0x555555559590, filename=filename@entry=0x555555559520 "/home/dan/Source/perl6/install/share/perl6/runtime/perl6.moarvm") at src/moar.c:504
#7  0x00005555555557c4 in main (argc=<optimized out>, argv=0x7fffffffe338) at src/vm/moar/runner/main.c:472
(gdb)