invalid looping over the `std::array<long double,..>` objects in PyROOT

[VanyaBelyaev]

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Description

Dear Experts

I've observed invalid &cobstrintuitive behavioos of loopingover std.array<lnog double,..> objects in PyRoot. It looks like __getitem__-based loop is correct, whle for-loop (__iter___ -based? )
produces weird results.
f

Reproducer

Reproducer is simple

import ROOT
std = ROOT.std

N  = 5 
A1 = std.array['int',N]
A2 = std.array['long double',N]

a1 = A1 ()
a2 = A2 ()

l1 = len ( a1 )
l2 = len ( a2 )

for i in range ( l1 ) : a1[i] = i
for i in range ( l2 ) : a2[i] = i

print ( 'a1:' , [ v for v in a1 ] , [ a1 [ i ] for i in range ( l1 ) ] ) 
print ( 'a2:' , [ v for v in a2 ] , [ a2 [ i ] for i in range ( l2 ) ] ) 

The output is

$ python ./tst_620.py
a1: [0, 1, 2, 3, 4] [0, 1, 2, 3, 4]
a2: [0, 0, 9223372036854775808, 16383, 9223372036854775808] [0.0, 1.0, 2.0, 3.0, 4.0]

ROOT version

ROOT 6.39 from LCG dev3 cvmfs nightly build

Installation method

LCG cvmfs nighly

Operating system

Linux

Additional context

No response

[guitargeek]

Thank you for the report. This bug was also communicated to me in meetings before, and now independently reported by you again. So that means it's worth fixing it for sure!