Avoid an useless and expensive call to PyUnicode_READ().

Previously, when an error was encountered some processes would not be
stopped until atexit callbacks were run.  On Windows that was too late
to prevent a PermissionError when regrtest tried to remove the temp
directory it ran the tests in.

associated pwd entry.

associated pwd entry.

of the second argument of PyUnicode_New().

 * Create also align_maxchar() function
 * Optimize fix_decimal_and_space_to_ascii(): don't compute the maximum
   character when ch <= 127 (it is ASCII)

 * formatfloat() uses unicode_fromascii() instead of PyUnicode_DecodeASCII()
   to not have to check characters, we know that it is really ASCII
 * Use PyUnicode_FromOrdinal() instead of _PyUnicode_FromUCS4() to format
   a character: if avoids a call to ucs4lib_find_max_char() to compute
   the maximum character (whereas we already know it, it is just the character
   itself)

Patch by Serhiy Storchaka.

issue13183 - Fix pdb skipping frames after hitting a breakpoint and running step. Patch by Xavier de Gaye

issue13183 - Fix pdb skipping frames after hitting a breakpoint and running step. Patch by Xavier de Gaye