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valgrind warning when allocating large amount of memory

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
42/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
cpp
Domain
data

Research direction

Start by compiling and running the program shown in the issue under Valgrind 3.15.0 with the reported GCC version. Read the Boost.MultiArray allocation path involved in constructing the seven-dimensional array and verify whether the large-range warnings indicate a library problem; done means identifying the cause and adding an appropriate regression test or documented resolution.

Written by the indexing model from the issue text.

Description

The following program:

#include "boost/multi_array.hpp"
using Emax = boost::multi_array<double, 7>; 

int main() {
    Emax emax(boost::extents[40][30][50][5][5][5][5]);
    return 0;
}

when run under valgrind gives the following warnings:

==20786== Memcheck, a memory error detector
==20786== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==20786== Using Valgrind-3.15.0 and LibVEX; rerun with -h for copyright info
==20786== Command: ./test_arr
==20786==
==20786== Warning: set address range perms: large range [0x5171040, 0x16f8b340) (undefined)
==20786== Warning: set address range perms: large range [0x5171028, 0x16f8b358) (noaccess)
==20786==
==20786== HEAP SUMMARY:
==20786==     in use at exit: 0 bytes in 0 blocks
==20786==   total heap usage: 2 allocs, 2 frees, 300,072,704 bytes allocated
==20786==
==20786== All heap blocks were freed -- no leaks are possible
==20786==
==20786== For lists of detected and suppressed errors, rerun with: -s
==20786== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

versions are:

gcc version 8.3.1 20190223 (Red Hat 8.3.1-2) (GCC)
valgrind-3.15.0
Dominant language
C++
Stars
32
Forks
39
PR merge metrics
No merged PRs in 30d

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