Followup to 90fc8980bb.
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GCC complains:
Python/pylifecycle.c: In function ‘_Py_InitializeFromConfig’:
Python/pylifecycle.c:900:13: warning: ‘interp’ may be used uninitialized in this function [-Wmaybe-uninitialized]
err = _Py_InitializeMainInterpreter(interp, &main_config);
~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This seems spurious since &interp is passed to _Py_InitializeCore. Anyway, we
can easily initialize to quiet the warning.
The recursive frame pruning code always undercounted the number of elided frames
by one. That is, in the "[Previous line repeated N more times]" message, N would
always be one too few. Near the recursive pruning cutoff, one frame could be
silently dropped. That situation is demonstrated in the OP of the bug report.
The fix is to start the identical frame counter at 1.
* A pointer in `PyInterpreterState_New()` could have been `NULL` when being dereferenced.
* Memory was leaked in `PyInterpreterState_New()` when taking some error-handling code path.
Use the core configuration of the interpreter, rather
than using global configuration variables. For example, replace
Py_QuietFlag with core_config->quiet.
* Py_FileSystemDefaultEncoding and Py_FileSystemDefaultEncodeErrors
default value is now NULL: initfsencoding() set them
during Python initialization.
* Document how Python chooses the filesystem encoding and error
handler.
* Add an assertion to _PyCoreConfig_Read().
Add support for the "surrogatepass" error handler in
PyUnicode_DecodeFSDefault() and PyUnicode_EncodeFSDefault()
for the UTF-8 encoding.
Changes:
* _Py_DecodeUTF8Ex() and _Py_EncodeUTF8Ex() now support the
surrogatepass error handler (_Py_ERROR_SURROGATEPASS).
* _Py_DecodeLocaleEx() and _Py_EncodeLocaleEx() now use
the _Py_error_handler enum instead of "int surrogateescape" to pass
the error handler. These functions now return -3 if the error
handler is unknown.
* Add unit tests on _Py_DecodeLocaleEx() and _Py_EncodeLocaleEx()
in test_codecs.
* Rename get_error_handler() to _Py_GetErrorHandler() and expose it
as a private function.
* _freeze_importlib doesn't need config.filesystem_errors="strict"
workaround anymore.
Py_DecodeLocale() and Py_EncodeLocale() now use the UTF-8 encoding on
Windows if Py_LegacyWindowsFSEncodingFlag is zero.
pymain_read_conf() now sets Py_LegacyWindowsFSEncodingFlag in its
loop, but restore its value at exit.
_PyCoreConfig_Read() is now responsible to choose the filesystem
encoding and error handler. Using Py_Main(), the encoding is now
chosen even before calling Py_Initialize().
_PyCoreConfig.filesystem_encoding is now the reference, instead of
Py_FileSystemDefaultEncoding, for the Python filesystem encoding.
Changes:
* Add filesystem_encoding and filesystem_errors to _PyCoreConfig
* _PyCoreConfig_Read() now reads the locale encoding for the file
system encoding.
* PyUnicode_EncodeFSDefault() and PyUnicode_DecodeFSDefaultAndSize()
now use the interpreter configuration rather than
Py_FileSystemDefaultEncoding and Py_FileSystemDefaultEncodeErrors
global configuration variables.
* Add _Py_SetFileSystemEncoding() and _Py_ClearFileSystemEncoding()
private functions to only modify Py_FileSystemDefaultEncoding and
Py_FileSystemDefaultEncodeErrors in coreconfig.c.
* _Py_CoerceLegacyLocale() now takes an int rather than
_PyCoreConfig for the warning.
On Windows, the LC_CTYPE is now set to the user preferred locale at
startup: _Py_SetLocaleFromEnv(LC_CTYPE) is now called during the
Python initialization. Previously, the LC_CTYPE locale was "C" at
startup, but changed when calling setlocale(LC_CTYPE, "") or
setlocale(LC_ALL, "").
pymain_read_conf() now also calls _Py_SetLocaleFromEnv(LC_CTYPE) to
behave as _Py_InitializeCore(). Moreover, it doesn't save/restore the
LC_ALL anymore.
On Windows, standard streams like sys.stdout now always use
surrogateescape error handler by default (ignore the locale).
Standard streams like sys.stdout now use the "surrogateescape" error
handler, instead of "strict", on the POSIX locale (when the C locale is not
coerced and the UTF-8 Mode is disabled).
Add tests on sys.stdout.errors with LC_ALL=POSIX.
* _Py_InitializeCore() now sets the LC_CTYPE locale to the user
preferred locale before checking if the C locale should be coerced
or not in _PyCoreConfig_Read().
* Fix pymain_read_conf(): remember if the C locale has been coerced
when the configuration should be read again if the encoding has
changed.
Python now gets the locale encoding with C code to initialize the encoding
of standard streams like sys.stdout. Moreover, the encoding is now
initialized to the Python codec name to get a normalized encoding name and
to ensure that the codec is loaded. The change avoids importing
_bootlocale and _locale modules at startup by default.
When the PYTHONIOENCODING environment variable only contains an encoding,
the error handler is now is now set explicitly to "strict".
Rename also get_default_standard_stream_error_handler() to
get_stdio_errors().
Reduce the buffer to format the "cpXXX" string (Windows locale encoding).
On HP-UX with C or POSIX locale, sys.getfilesystemencoding() now returns
"ascii" instead of "roman8" (when the UTF-8 Mode is disabled and the C locale
is not coerced).
nl_langinfo(CODESET) announces "roman8" whereas it uses the Latin1
encoding in practice.
* The UTF-8 Mode is now also enabled by the "POSIX" locale, not only
by the "C" locale.
* On FreeBSD, Py_DecodeLocale() and Py_EncodeLocale() now also forces
the ASCII encoding if the LC_CTYPE locale is "POSIX", not only if
the LC_CTYPE locale is "C".
* test_utf8_mode.test_cmd_line() checks also that the command line
arguments are decoded from UTF-8 when the the UTF-8 Mode is enabled
with POSIX locale or C locale.
