[Bug]: float.__pow__ silently returns `inf` instead of raising `OverflowError` when the result overflows

[jseop-lim]

Describe the bug

Description

pow() on float operands silently returns float('inf') when the mathematical result exceeds Double.MAX_VALUE, instead of raising OverflowError as CPython does. This is a CPython compatibility issue that affects pow(float, int), pow(float, float), and pow(int, float) call forms.

Root Cause

FloatBuiltins.PowNode.doOperation returns Math.pow(left, right) directly and never checks Double.isInfinite(result), so an overflow silently surfaces as a float value. The same missing check exists in the sibling specializations doDD and doDDToComplex, which are reached by pow(float, float) and pow(int, float) respectively.

• FloatBuiltins.java#L503-L508 — doOperation
• FloatBuiltins.java#L510-L526 — doDD
• FloatBuiltins.java#L528-L543 — doDDToComplex

For reference, other paths in the same file already perform this defense (fromhex at lines 653-654, round at 805-806, __int__ at 833-834) — only pow is missing it, breaking in-file consistency.

CPython reference: Objects/floatobject.c#L847-L860

// CPython forces errno = ERANGE when libm pow() overflows to ±HUGE_VAL,
// and then raises OverflowError from errno.
errno = 0;
ix = pow(iv, iw);
_Py_ADJUST_ERANGE1(ix);         // if (x == ±Py_HUGE_VAL) errno = ERANGE;
...
if (errno != 0) {
    PyErr_SetFromErrno(errno == ERANGE ? PyExc_OverflowError
                                        : PyExc_ValueError);
    return NULL;
}

Fix

In all three specializations (doOperation, doDD, doDDToComplex), after calling Math.pow(left, right), raise OverflowError when the result is ±Infinity while both inputs are finite (the Java equivalent of _Py_ADJUST_ERANGE1).

Reproduction

result = pow(8520.852079253338, 965168)
print(result, type(result))

Output

GraalPy:

inf <class 'float'>

CPython:

Traceback (most recent call last):
  File "/path/to/test.py", line 1, in <module>
    result = pow(8520.852079253338, 965168)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
OverflowError: (34, 'Numerical result out of range')

Environment

• GraalPy 25.0.2 (Python 3.12.8)
• CPython 3.12.13
• OS: Debian 12