Message-Id: <199907182318.XAA97834@out5.ibm.net>
From: "Mark E." <snowball3 AT bigfoot DOT com>
To: djgpp-workers AT delorie DOT com
Date: Sun, 18 Jul 1999 19:18:30 -0400
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Subject: binutils in CVS
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Reply-To: djgpp-workers AT delorie DOT com


Hello folks,

There's not much COFF development going on in binutils, except for 
PE-COFF, but there still some things that need some attention.

First, I've ported the ".gnu.linkonce" extension previously available only 
to ELF targetsto COFF. This feature, together with weak symbol 
support, enables the automatic C++ template support PE COFF 
(Win32) and ELF systems have. The price for this improved support is 
bigger object files where the template code is used. However, this 
bloat is removed at link time. The ".gnu.linkonce" feature does require 
COFF long section name support to be enabled. This is not a problem 
since everything ends up in sections with short names, which are 
stored the same way wether or not long section support is enabled.  
dgpp.djl will need some minor changes to handle the new feature:

*** djgpp.djm	Sun Jul 12 22:53:46 1998
--- djgpp.djl	Sun Jul 18 00:07:16 1999
*************** SECTIONS
*** 4,9 ****
--- 4,10 ----
  {
    .text  0x1000+SIZEOF_HEADERS : {
      *(.text)
+     *(.gnu.linkonce.t*)
      etext  =  . ; _etext = .;
      . = ALIGN(0x200);
    }
*************** SECTIONS
*** 15,23 ****
      *(.dtor)
      djgpp_last_dtor = . ;
      *(.data)
!     *(.gcc_exc)
      ___EH_FRAME_BEGIN__ = . ;
!     *(.eh_fram)
      ___EH_FRAME_END__ = . ;
      LONG(0)
       edata  =  . ; _edata = .;
--- 16,26 ----
      *(.dtor)
      djgpp_last_dtor = . ;
      *(.data)
!     *(.gnu.linkonce.d*)
!     *(.gnu.linkonce.r*)
!     *(.gcc_exc*)
      ___EH_FRAME_BEGIN__ = . ;
!     *(.eh_fram*)
      ___EH_FRAME_END__ = . ;
      LONG(0)
       edata  =  . ; _edata = .;

But this is something that can be handled in the DJGPP port of 2.10 
(the patch was just for illustration). gcc will need some minor changes 
to DJGPP's config files to enable the compiler to use this feature. 
However, I'm not sure when to submit the gcc changes because then 
that would require C++ users to have 2.10 and no telling when it will be 
released given how long it's been in development.  

The bring me to a couple of minor things that could use some 
attention. The linker script template currently in CVS doesn't contain the 
C++ EH support like djgpp.djl does.

ldmain.c contains code that tries to add 
'$DJDIR/$target_alias/ldscripts/' to the library path, where target_alias 
expands to i[3456]86-pc-msdosdjgpp. But this isn't a major problem, 
since the scripts can be anywhere in the library path.


--- 
Mark Elbrecht, snowball3 AT bigfoot DOT com
http://snowball.frogspace.net/