From: naga raj <gnuuser.raj@gmail.com>
To: Jonathan Wakely <jwakely.gcc@gmail.com>, Andrew Haley <aph@redhat.com>
Cc: gcc-help <gcc-help@gcc.gnu.org>
Subject: Re: libstdc++
Date: Mon, 27 Aug 2012 09:27:00 -0000 [thread overview]
Message-ID: <CAKuVEhDExdpV1q3B7_HveqmZ_Pe60ery71U5GVq+j4_ZmPrUnQ@mail.gmail.com> (raw)
In-Reply-To: <CAH6eHdRpxoPerOwyf0kPhJjCvJDZQqpC7xYCZpu3wj_Va9yjZg@mail.gmail.com>
Hi Jonathan/Andrew
Thank you very much for your responses.
I think I have to select a subset of the C++ standard libraries and
implement a smaller library.
Thanks,
Nagaraju
On Fri, Aug 24, 2012 at 3:09 PM, Jonathan Wakely <jwakely.gcc@gmail.com> wrote:
> On 24 August 2012 08:46, naga raj wrote:
>> Hi,
>>
>> I have ported Gcc-4.6.2 to an embedded target. My C++ compiler is
>> generating huge code size.
>>
>> #include <iostream>
>> using namespace std;
>> int main()
>> {
>> return 0;
>> }
>>
>> If we execute the above program then all the function in the
>> iostream library are included in the elf as a result size of elf is
>> increased....
>
> Including <iostream> causes global objects to be constructed, so even
> though you're not explicitly using std::cout or std::cin, those
> streams are initialized and code is run (before main) just because
> <iostream> is included. If you don't need to use it then don't
> include it. If you do need to use it then obviously the code size is
> larger if you use I/O features than if you don't use them.
>
> That said, libstdc++ isn't really optimised for embedded systems.
> Some configure-time options such as building libstdc++ without
> exceptions can help reduce code size, if you don't need to use
> exceptions.
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43852 would also help
> avoid dependency on the I/O facilities.
next prev parent reply other threads:[~2012-08-27 5:00 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-24 8:10 libstdc++ naga raj
2012-08-24 9:33 ` libstdc++ Andrew Haley
2012-08-24 13:40 ` libstdc++ Jonathan Wakely
2012-08-27 9:27 ` naga raj [this message]
-- strict thread matches above, loose matches on Subject: below --
1999-11-04 18:42 libstdc++ Inferno
1999-11-07 5:16 ` libstdc++ J.H.M. Dassen (Ray)
1999-11-30 23:28 ` libstdc++ J.H.M. Dassen (Ray)
1999-11-30 23:28 ` libstdc++ Inferno
1999-10-01 0:00 libstdc++ Inferno
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