* test/src/comp-tests.el (comp-deftest): Ensure that no files are left
behind (bug#55611).

* test/src/buffer-tests.el (test-restore-buffer-modified-p): Clean
up autosave file in /tmp.

When printing a circular list and `print-circle` is nil, use a
somewhat more meaningful ". #N" tail index.  The previous method for
calculating that index was based on Floyd circularity detection being
used so it had been broken ever since the change to Brent's algorithm.

The new index is correct with respect to the start of the list itself
which is what it used to be before being completely broken.
It does not take into account the nesting depth of the list context.

* src/print.c (struct print_stack_entry, print_object):
Keep track of the tortoise index (which is cheap) instead of trying
to derive it from the printed element index.
* test/src/print-tests.el (print-test-rho, print-circular):
New test.

Introduce explicit stacks for traversing common data types during
printing: conses, vectors, records, byte-code, hash-tables and
char-tables, all previously traversed using recursion in C.  This
greatly reduces the risk of crashing Emacs from C stack overflow
when printing deeply nested data.

* src/print.c (Fprinc, print, PRINT_CIRCLE_CANDIDATE_P):
Special-case Fprinc with a plain string argument to eliminate the need
for keeping track of print_depth during the preprocessing phase.
This also improves performance.
(struct print_pp_entry, struct print_pp_stack, ppstack)
(grow_pp_stack, pp_stack_push_value, pp_stack_push_values)
(pp_stack_empty_p, pp_stack_pop):
New stack for preprocessing.
(print_preprocess):
Make mostly nonrecursive, except for string properties.
(enum print_entry_type, struct print_stack_entry)
(struct print_stack, prstack, grow_print_stack)
(print_stack_push, print_stack_push_vector):
New stack for printing.
(print_vectorlike, print_object):
Make mostly nonrecursive, except for string properties and some less
heavily used types.
* test/src/print-tests.el (print-deeply-nested):
New test.

* doc/lispref/streams.texi (Output Functions): Document it.
(Output Overrides): New node.

* src/process.c (Faccept_process_output):
* src/print.c (debug_print, print_error_message):
* src/pdumper.c (print_paths_to_root_1, decode_emacs_reloc):
* src/lread.c (readevalloop):
* src/eval.c (internal_lisp_condition_case):
* src/editfns.c (styled_format): Adjust prin1/prin1-to-string
callers.

* src/print.c (Fprin1): Take an OVERRIDES parameter.
(print_bind_overrides, print_bind_all_defaults): New functions.
(Fprin1_to_string): Take an OVERRIDES parameter.

* doc/lispref/buffers.texi (Buffer Modification): Adjust
documentation.

* src/buffer.c (Frestore_buffer_modified_p): Fix up the logic
around `autosaved': It means "the buffer is modified, and also
autosaved".

* doc/lispref/buffers.texi (Buffer Modification): Document
buffer-modified-p returning `autosaved'.
* lisp/subr.el (with-silent-modifications): Use
restore-buffer-modified-p instead of altering the buffer modiff
(since this has other side effects like not updating after async
`display' changes.

* src/buffer.c (Fbuffer_modified_p): Allow returning whether the
buffer has been autosaved after changes.
(Frestore_buffer_modified_p): Allow adjusting whether the buffer
has been autosaved after changes.

* src/fileio.c (Fdo_auto_save): Refill the doc string.

* doc/lispref/text.texi (Database): Document how to insert binary
data.
* src/sqlite.c (bind_values): Bind BLOB columns correctly (bug#54591).

* src/timefns.c (Fencode_time): Add support for a 6-elt list arg.
Requested by Max Nikulin for Org (bug#54764).
* test/src/timefns-tests.el (encode-time-alternate-apis): New test.