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Re: [clang] -Os invalid content of argc+argv

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On Thu, 03 Sep 2015 16:43:58 -0700
Keith Thompson <kst-u@mib.org> wrote:

> Melzzzzz <mel@zzzzz.com> writes:
> [...]
> > I don't know about cygwin but argc/argv values are parsed with crt 
> > on Linux. That is if you link with c runtime and write main in
> > assembler you get already parsed values eg Linux passes values on
> > stack but crt parses them into rdi,rsi registers...
> > Probably on cygwin compiler parses those values therefore bug.
> 
> The command line is parsed by the shell, which then passes them to
> your program using one of the exec*() functions.
> 
> The compiler doesn't parse your program's command line arguments
> (because they don't exist yet).  It merely generates code that is able
> to receive those arguments via the argc and argv parameters.
> 

Hm, when I don't link with crt, rather make assembly executable
independently, I don;t have argc,argv parameters as function
arguments at all, rather they are laid down on stack... at least on
x86-64 Linux...
Of course shell parses command line but what I actually meant is that
crt parses stack and forms argc,argv as standard function parameters
(rdi->argc (first function parameter),rsi->argv (second function
parameter).

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[clang] -Os invalid content of argc+argv m.labanowicz@gmail.com - 2015-09-03 13:28 -0700
  Re: [clang] -Os invalid content of argc+argv Melzzzzz <mel@zzzzz.com> - 2015-09-03 23:31 +0200
    Re: [clang] -Os invalid content of argc+argv Keith Thompson <kst-u@mib.org> - 2015-09-03 16:43 -0700
      Re: [clang] -Os invalid content of argc+argv Melzzzzz <mel@zzzzz.com> - 2015-09-04 01:53 +0200
      Re: [clang] -Os invalid content of argc+argv Philip Lantz <prl@canterey.us> - 2015-09-03 20:15 -0700
        Re: [clang] -Os invalid content of argc+argv Keith Thompson <kst-u@mib.org> - 2015-09-04 09:15 -0700
          Re: [clang] -Os invalid content of argc+argv m.labanowicz@gmail.com - 2015-09-04 10:33 -0700
            Re: [clang] -Os invalid content of argc+argv Noob <root@127.0.0.1> - 2015-09-04 20:48 +0200

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