Re: GCC link problem help!

[Xi Ruoyao <xry111@mengyan1223.wang>]

On Wed, 2021-10-20 at 22:53 +0800, 桂永林 wrote:
> Hellow Tom and Liu Hao,
>    We encounter another GCC link problem. Our hardware is cotex-M33
> platform,  our software project development on windows environment and
> use GCC compiler and the gcc-linker as bellow:
> 
> 
>    gcc version 7.3.1 20180622 (release) [ARM/embedded-7-branch
> revision 261907] (GNU Tools for Arm Embedded Processors 7-2018-q2-
> update)
> 
>    GCC: GNU ISO C11  7 2018-q2-update 
> 
>    GCC parameter:  -std=gnu11
> 
>    gcc-linker parameter: --specs=nano.specs --specs=nosys.specs
>    
>    Our project need link a C++ static lib into our project. The C++
> lib build enviroment as bellow:
>    G++：GNU ISO 2011 C++
>    G++ parameter：-std=gnu++11 -fabi-version=0 -fno-exceptions -fno-
> rtti -fno-use-cxa-atexit -fno-non-call-exceptions
> 
> 
> 
>    But we found that if we linked the C++ static lib to our program,
> then the program have runtime logic problem sometimes. If we do not
> link the C++ lib, it can run well. We can not understand why the
> reason. We guess, if maybe some gcc linker parameter need used when we
> need link the C++ lib? 

>    Can you give us some suggest about how to fix this problem!   

I think it will be very difficult to tell.  Maybe there is some
undefined behavior (for example, out-of-bound access) in your program
and linking in libstdc++ just changes the memory layout or something and
exploits the issue.  The undefined behavior may be even triggered by
some hardware problem for a embedded system...  (I once debugged my
program for one day and then found out one capacitor was simply too
small!)
-- 
Xi Ruoyao <xry111@mengyan1223.wang>
School of Aerospace Science and Technology, Xidian University