RE: dll create problem with gcc configured with arm-pe

["longchuan" <longchuan at koretide dot com dot cn>]

Hi Nick and all fellows :
I think this patch is not enough to create dll with relocation. gcc is
configured as ARM-WINCE-PE.
when i debug this dll, and found that the export table was overridden by
relocation fixup.
with objdump -x counter.dll, it show that:
.....
Entry 0 00006000 00001902 Export Directory [.edata (or where ever we
found it)]
....
There is an export table in .edata at 0x10006000

The Export Tables (interpreted .edata section contents)

Export Flags 			0
Time/Date stamp 		3e9cf9b3
Major/Minor 			0/0
Name 				00006028 counter.dll
Ordinal Base 			1
Number in:
	Export Address Table 		00000004
	[Name Pointer/Ordinal] Table	00000004
Table Addresses
	Export Address Table 		00006040
.......
Virtual Address: 00006000 Chunk size 32 (0x20) Number of fixups 12
	reloc    0 offset    c [600c] HIGHLOW
	reloc    1 offset   1c [601c] HIGHLOW
	reloc    2 offset   20 [6020] HIGHLOW
	reloc    3 offset   24 [6024] HIGHLOW
	reloc    4 offset   40 [6040] HIGHLOW
	reloc    5 offset   44 [6044] HIGHLOW
......

So, address 0x10006040 is corrupted, that is address of export table.

I am sorry i don't have much knowledge about dll relocation, but i
compare with mingw32 for win32 gcc, compiling 
the same program, and the result is:
...........
Entry 0 00005000 0000196c Export Directory [.edata (or where ever we
found it)]
............
The Export Tables (interpreted .edata section contents)

Export Flags 			0
Time/Date stamp 		3e9ba05b
Major/Minor 			0/0
Name 				00005028 counter.dll
Ordinal Base 			1
Number in:
	Export Address Table 		00000004
	[Name Pointer/Ordinal] Table	00000004
Table Addresses
	Export Address Table 		00005034
.....
no relocation information point to export table address, I think that is
the different.

did I make myself clear? what do you think about this?

regards,
wreckor

> -----Original Message-----
> From: nickc at workshop dot nickc dot cambridge dot redhat dot com 
> [mailto:nickc at workshop dot nickc dot cambridge dot redhat dot com] On Behalf 
> Of Nick Clifton
> Sent: Tuesday, April 01, 2003 00:05
> To: longchuan
> Cc: binutils at sources dot redhat dot com
> Subject: Re: dll create problem with gcc configured with arm-pe
> 
> 
> Hi Wreckor,
> 
> > ld failed with message:
> > Cannot export TestFunc: symbol not defined
> > test.exp(.edata+0x40): undefined reference to `TestFunc'
> 
> As you have already noted, the first thing you need to change 
> is the exports in your test.def file, prefixing an underscore 
> to TestFunc,
> ie:
> 
>         LIBRARY test.dll
>         EXPORTS
>                 _TestFunc
> 
> This takes care of the second error message.
> 
> > I add a leading underscore to def file i.e from TestFunc to 
> _TestFunc 
> > in test.def and in ld option, i omit -shared option, this 
> time i could 
> > get the dll file but i don't think this one is what i 
> expected. This 
> > dll don't have relocation table.
> 
> Well without the -shared option the relocations are 
> discarded, so the linker is operating correctly.  (This is 
> because in a non-shared executable, all of the relocations 
> should have been resolved, so there is no need for the 
> relocation table).
> 
> The real problem however is a bug in the linker.  Try 
> applying the patch below and then rerunning LD, but this 
> time, include the -shared command line option.
> 
> If this fixes your problem, please let me know so that the 
> patch can be applied to the sources.
> 
> Cheers
>         Nick
> 
> ld/ChangeLog
> 2003-03-31  Nick Clifton  <nickc at redhat dot com>
> 
> 	* pe-dll.c (pe_detail_list): The pe-arm target does use 
> underscores.
> 
> Index: ld/pe-dll.c 
> ===================================================================
> RCS file: /cvs/src/src/ld/pe-dll.c,v
> retrieving revision 1.55
> diff -c -3 -p -w -r1.55 pe-dll.c
> *** ld/pe-dll.c	21 Feb 2003 10:51:24 -0000	1.55
> --- ld/pe-dll.c	31 Mar 2003 15:59:31 -0000
> *************** static pe_details_type pe_detail_list[] 
> *** 199,205 ****
>       11 /* ARM_RVA32 */,
>       PE_ARCH_arm,
>       bfd_arch_arm,
> !     0
>     },
>     {
>       "epoc-pei-arm-little",
> --- 199,205 ----
>       11 /* ARM_RVA32 */,
>       PE_ARCH_arm,
>       bfd_arch_arm,
> !     1
>     },
>     {
>       "epoc-pei-arm-little",
> 
>