DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:message-id:date:from:reply-to:to:subject
	:mime-version:content-type:content-transfer-encoding; q=dns; s=
	default; b=WAnN15l1g6BBfjbfLXDOhIWyIKnUG0CiKeX6v4dIKLyo/XKiQpszt
	c6L63VkE98nIxSozzma4TriXqbMf+1+0WnnpXLAcJT2OdfXD9eOBjt2+anZQ8Qql
	4F8LwJxT2jf6uaxarMilcdM8A+BqGFvzb9ylljuxhdq5UZotaY0ADc=
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Message-ID: <2137976859.11219481456057694503.JavaMail.httpd@webmail-48.iol.local>
Date: Sun, 21 Feb 2016 13:28:14 +0100 (CET)
From: Carlo Bramini <carlo DOT bramix AT libero DOT it>
Reply-To: Carlo Bramini <carlo DOT bramix AT libero DOT it>
To: cygwin AT cygwin DOT com
Subject: LIBGCC startup code: you cannot hide GetProcAddress AT 8 and GetModuleHandleA AT 4
MIME-Version: 1.0
Content-Type: text/plain;charset="UTF-8"
Content-Transfer-Encoding: 7bit

Let's assume to have this simple C source code:


void * __stdcall GetProcAddress( int hModule, char * function )
{
    return 0;
}

void * __stdcall GetModuleHandleA( char * Module )
{
    return 0;
}

int main()
{
    return 0;
}


if you try to compile it, you will get:

/usr/lib/w32api/libkernel32.a(deijs00581.o):(.text+0x0): multiple definition 
of `GetProcAddress AT 8'
/tmp/ccMGY4R3.o:t.c:(.text+0x0): first defined here
/usr/lib/w32api/libkernel32.a(deijs00533.o):(.text+0x0): multiple definition 
of `GetModuleHandleA AT 4'
/tmp/ccMGY4R3.o:t.c:(.text+0xc): first defined here
collect2: error: ld returned 1 exit status

In my opinion, it is a bug or, if you prefer, a limitation in the startup 
code.
I think that this happens because gcc/config/i386/cygming-crtbegin.c always 
uses GetProcAddress() and GetModuleHandleA() API, even when you feed -static 
option at command line.
I understand that there are not too much ways for importing stuff from 
cyggcc_s-1.dll, but I think this limitation could be also overcome in a simple 
way.
Perhaps, besides crtbegin.o and crtbeginS.o, CYGWIN toolchain should also 
allow use crtbeginT.o (it seems to me that it is actually missing), for having 
the real static linking when you provide "-static" on the command line. The 
source file with an additional #ifdef...#endif will just call 
__register_frame_info, _Jv_RegisterClasses and __deregister_frame_info 
functions without much worries.

I'm using:
gcc version 5.3.0 (GCC)
but it also happens with GCC4

Sincerely,

Carlo Bramini.

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple