On Fri, Jun 30, 2023 at 9:11 AM Xi Ruoyao <xry111@xry111.site> wrote:

> On Fri, 2023-06-30 at 08:28 +0200, Jędrzej Dudkiewicz via Gcc-help wrote:
> > This is basically the same as
> >
> https://stackoverflow.com/questions/76580329/hide-symbols-from-executable
> > I pasted it below in its entirety.
> >
> > If this is primarily a binutils question I will paste it there, but I
> > *think* it is mostly a gcc related question.
> >
> > ------8< ------8< ------8< ------8< ------8< ------8< ------8< ------
> > <https://stackoverflow.com/posts/76580329/timeline>
> >
> > I use gcc 9.2.0 to compile c++ program for arm. I use boost 1.71.0
> (mainly
> > asio). My final executable works fine, but even after stripping readelf
> -W
> > prog --dyn-syms shows e.g. these entries:
> >
> >    904: 000dc518     1 OBJECT  UNIQUE DEFAULT   25
> >
> _ZN5boost4asio6detail30execution_context_service_baseINS1_16resolver_serviceINS0_2ip3tcpEEEE2idE
> >    912: 000dc498     1 OBJECT  UNIQUE DEFAULT   25
> >
> _ZN5boost4asio6detail30execution_context_service_baseINS1_18signal_set_serviceEE2idE
> >    943: 000dc46c     4 OBJECT  UNIQUE DEFAULT   25
> >
> _ZN5boost4asio6detail17posix_global_implINS0_14system_contextEE11static_ptr_E
> >    951: 000dc4b0     1 OBJECT  UNIQUE DEFAULT   25
> > _ZN5boost4asio6detail12service_baseINS1_14strand_serviceEE2idE
> >    990: 000dc48c     4 OBJECT  UNIQUE DEFAULT   25
> >
> _ZGVN5boost4asio6detail10call_stackINS1_14strand_service11strand_implEhE4top_E
> >   1005: 0009a484    38 OBJECT  WEAK   DEFAULT   15
> > _ZTSN5boost4asio22service_already_existsE
> >   1006: 000a3808    87 OBJECT  WEAK   DEFAULT   15
> >
> _ZTSN5boost16exception_detail10clone_implINS0_19error_info_injectorINS_12bad_any_castEEEEE
> >   1024: 0009ad9c    65 OBJECT  WEAK   DEFAULT   15
> > _ZTSN5boost16exception_detail19error_info_injectorISt11logic_errorEE
> >   1038: 0009ee34   128 OBJECT  WEAK   DEFAULT   15
> >
> _ZTSN5boost4asio6detail30execution_context_service_baseINS1_22deadline_timer_serviceINS0_11time_traitsINS_10posix_time5ptimeEEEEEEE
> >   1045: 0009ade0    84 OBJECT  WEAK   DEFAULT   15
> >
> _ZTSN5boost16exception_detail10clone_implINS0_19error_info_injectorISt11logic_errorEEEE
> >
> > As far as I can tell, these symbols are known to the compiler/linker, as
> > their Ndx is not UND (so undefined), which means their presence in the
> > symbol table is not necessary. Since the whole program has 690kB and as
> > strings shows these entries in the symbol table take more or less 140kB,
> > I'd like to remove them.
> >
> > Currently I am compiling using the following compiler/linker options:
> > -fvisibility=hidden -fvisibility-inlines-hidden -flto
> -Wl,--exclude-libs,ALL
> > -Wl,-r,--discard-all -Wl,-flto
>
> Hmm, isn't "-r" for partial linking?  How can you use it to link an
> executable?
>

Well, final binary works so I suppose it simply makes no difference. Reason
for it being here is simple: I've been trying basically all combinations of
options that according to The Experts Of The Internet should somehow make
my binary smaller. Since this is combination that ended with smallest
binary.
-- 
Jędrzej Dudkiewicz

I really hate this damn machine, I wish that they would sell it.
It never does just what I want, but only what I tell it.