Re: Extra import symbol in debug build

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 2023-02-17 11:26, Jonathan Wakely wrote:
On Fri, 17 Feb 2023, 08:51 , <i.nixman@xxxxxxxxxxxxx> wrote:

On 2023-02-16 20:08, Jonathan Wakely wrote:
> On Thu, 16 Feb 2023, 18:39 , <i.nixman@xxxxxxxxxxxxx> wrote:
>
>> On 2023-02-16 15:29, Jonathan Wakely wrote:
>> > On Thu, 16 Feb 2023 at 15:25, i.nixman--- via Gcc-help
>> > <gcc-help@xxxxxxxxxxx> wrote:
>> >>
>> >> hello,
>> >>
>> >>
>> >> I can successfully build the same C++ code using GCC-8.3.1 for Debug
>> >> (-g
>> >> -O0) and Release (-g -O2) build.
>> >> I can successfully debug the Release-executable on a remote host, but
>> >> I
>> >> can't debug the Debug-executable on a remote host, because the
>> >> Debug-executable imports an extra symbol
>> >> _ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv from libstdc++ which
>> >> doesn't
>> >> exist.
>> >
>> > It should exist, it has been there since GCC
>>
>> hmm...
>>
>> I just checked the two binaries using this cmd:
>>
>> > readelf -sW executable | grep
>> > _ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv
>>
>> it shows nothing for release build, and shows this for debug build:
>>
>> >     54: 0000000000000000     0 FUNC    GLOBAL DEFAULT  UND
>> > _ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv
>> > 199898: 0000000000000000     0 FUNC    GLOBAL DEFAULT  UND
>> > _ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv
>>
>
>
> This only shows that the function is inlined in the optimized build,
> and
> not in the debug build, so the debug one has an unresolved reference to
> a
> symbol defined in the libstdc++ dynamic library. This is completely
> normal.
>

then I have two questions:

1. will the problem be solved by "pushing" a debug version of libstdc++
on the remote machine?


You don't need a debug version, the symbol is present in all builds of
libstdc++.

hmm..
but I can't confirm that using this cmd:
readelf -sW /lib64/libstdc++.so.6 | grep _ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv




[Index of Archives]     [Linux C Programming]     [Linux Kernel]     [eCos]     [Fedora Development]     [Fedora Announce]     [Autoconf]     [The DWARVES Debugging Tools]     [Yosemite Campsites]     [Yosemite News]     [Linux GCC]

  Powered by Linux