Re: RFA: Some question I found while reviewing coffcode

[Kai Tietz <Kai dot Tietz at onevision dot com>]

binutils-owner@sourceware.org wrote on 13.01.2009 06:53:01:

> "Kai Tietz" <ktietz70@googlemail.com> writes:
> 
> > while reviewing the coff code I found some problems in our current
> > implementation
> 
> Note that you are discussing PE, not COFF.  COFF is a much older
> object file format, PE is an extension.

Well, I am aware that COFF means typically just the object file format. 
But PE/PE+ are imagefile formats based on COFF, not an extension IMHO.

> > 1) Treating of IMAGE_SCN_LNK_INFO
> >    As coff spec says "The section contains comments or other
> > information. The .drectve section has this type. This is valid for
> > object files only." and "A section is a directive section if it has
> > the IMAGE_SCN_LNK_INFO flag set in the section header and has the
> > .drectve section name. The linker removes a .drectve section after
> > processing the information, so the section does not appear in the
> > image file that is being linked. "
> > At the moment are sections with the IMAGE_SCN_LNK_INFO flag mark as
> > SEC_DEBUGGING (when COFF_PAGE_SIZE is known). But at least for the
> > .drectve it should be SEC_EXCLUDE, IIUC.
> 
> Yes.  This should probably be set in process_def_file in ld/pe-dll.c.
I agree, that the interpretation of some of those linker directives can be 
done in ld/pe-dll.c, but the real change here is in coffcode.h. Because 
here it is marked as SEC_DEBUGGING, which means strip happily remove those 
information, but IIUC they should be removed by ld itself.

> > 2) Treating of IMAGE_SCN_MEM_NOT_PAGED
> >   Is untreated. For user mode this flag is not of much interest, but
> > for drivers and kernel mode things it is pretty important to mark
> > sections as not to be page-able  Do we need here an addtional COFF
> > flag for this?
> 
> I suppose you could add a new SEC_xxx flag for this--we already have
> COFF specific SEC_xxx flags.  Or it might be possible to add a field
> to the coff_section_tdata struct.

Thanks for the suggestion. I think an additional field in 
coff_section_tdata about the paging/loading behaviour for 
DISCARDABLE/NOT_PAGED/PAGED would be best. I will prepare a patch for 
this.

Cheers,
Kai

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