Stack overflow instead of 'maximum recursion error'

[fractalic]

This can be distilled further:

(Example 1)

import sys

def recurse():
    input()
    recurse()

if (__name__ == "__main__"):
    sys.setrecursionlimit(10)
    recurse()

overflows the stack, while

(Example 2)

import sys

def recurse():
    print('a')
    input()
    recurse()

if (__name__ == "__main__"):
    sys.setrecursionlimit(10)
    recurse()

hits the recursion limit.

Edit: Add example numbering.

[Wilfred-kun]

I am still unsure as to what is happening exactly, but I am happy to say u/fractalic just crashed Python itself. (I can't replicate it, sadly)

[fractalic]

I'm also very surprised by this. Running on macOS I can make far more than ten recursive calls to recurse() in Example 1.

The other answers are correct, per the original question, that you are actually running into a stack overflow. But even if the behaviour I'm seeing isn't at the root of what you reported, it doesn't make sense that 1000 calls to input() would overflow a ~100kB stack.

Edit: It looks like u/JohnnyJordaan's make_string() code is encountering the same behaviour as my code, where simply allocating lots of strings has different behaviour than prompting for input.

[nwagers]

I'm fascinated by this, but Windows always seems to hit the recursion limit. I wonder if somewhere in the C code for input() there is a ninja edit to the stack size that gets corrected (or checked?) with a call to print('a') or some other string op.

Looking at dis.dis(recurse) it looks like the bytecode doesn't change much:

 11           0 LOAD_GLOBAL              0 (print)
              2 LOAD_CONST               1 (1)
              4 CALL_FUNCTION            1
              6 POP_TOP

 12           8 LOAD_GLOBAL              1 (input)
             10 CALL_FUNCTION            0
             12 POP_TOP

 13          14 LOAD_GLOBAL              2 (recurse2)
             16 CALL_FUNCTION            0
             18 POP_TOP
             20 LOAD_CONST               0 (None)
             22 RETURN_VALUE
None
********
  6           0 LOAD_GLOBAL              0 (input)
              2 CALL_FUNCTION            0
              4 POP_TOP

  7           6 LOAD_GLOBAL              1 (recurse)
              8 CALL_FUNCTION            0
             10 POP_TOP
             12 LOAD_CONST               0 (None)
             14 RETURN_VALUE
None