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Issue #789290: make sure that hash(2**63) == hash(2.**63) on 64-bit

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platforms.  The previous code was fragile, depending on the twin
accidents that:

  (1) in C, casting the double value 2.**63 to long returns the integer
      value -2**63, and
  (2) in Python, hash(-2**63) == hash(2**63).

There's already a test for this in test_hash.
This commit is contained in:
Mark Dickinson 2009-02-08 14:42:28 +00:00
parent c5e68b1898
commit 10fe877dcd
1 changed files with 1 additions and 1 deletions
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2
Objects/object.c
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@ -1028,7 +1028,7 @@ _Py_HashDouble(double v)
fractpart = modf(v, &intpart);
if (fractpart == 0.0) {
/* This must return the same hash as an equal int or long. */
if (intpart > LONG_MAX || -intpart > LONG_MAX) {
if (intpart > LONG_MAX/2 || -intpart > LONG_MAX/2) {
/* Convert to long and use its hash. */
PyObject *plong; /* converted to Python long */
if (Py_IS_INFINITY(intpart))