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Re: [Patch mach-o, indirect symbols 1/2] support indirect symbols in mach-o.

Hi Tristan,

On 4 Jan 2012, at 08:26, Tristan Gingold wrote:
Well, OK, the simplest solution is to keep the code mechanism as is - but to use a new/different flag to signal .indirect_symbols .. the sorting etc. doesn't really need to change (just the bits using IS_MACHO_INDIRECT - which needs to utilize a different flag) .. any suggestions about the Right Flag (or a new one)?

The GAS end will need amending to use a SET_MACHO_INDIRECT .. but that's also not too too bad...

So, here's a revised patch -
that uses (BSF_INDIRECT | BSF_SYNTHETIC) as the 'signal' from gas - > bfd that the symbol is a mach_o .indirect_symbol
these symbols are also unnamed (could be used as a third key if there is a meaning - can't think of one tonight - to (BSF_INDIRECT | BSF_SYNTHETIC)).

I think we should really moving .indirect_symbols out of the symtab for the following reasons:
1) there is no natural flags for them (BSF_INDIRECT | BSF_SYNTHETIC is not fully correct)
2) they are anonymous (so it doesn't make sense to create a symbol for them)
3) they aren't physically in the symtab
4) they're values are well defined.
5) there is a symmetry violation: when we read a mach-o file, we don't create symbol for .indirect_symbol, but we will need symbols to create .indirect_symbol. This will lead to trouble for objcopy and co.
If you don't agree, please argue!

Those seem good reasons to me too.

So .. what about a new obstack for these in obj-macho.c?
and, I suppose, a private interface for passing them to BFD.


I'll repost the symbol quals patch if you like - since there's quite a lot to remove (or are you OK with me removing and applying?)

+  do
+    {
+      name = input_line_pointer;
+      c = get_symbol_end ();
+      symbolP = symbol_find_or_make (name);
+      err = obj_mach_o_set_symbol_qualifier (symbolP, ntype);
+      *input_line_pointer = c;
+      if (err)
+	break;

Do we need to break in case of error ?

... I'm not a fan of a flurry of errors for one typo ..
(but I suppose we should also do an 'ignore_rest_of_Line' as well)

I'll remove it for now, and we can see how that works out.

thanks for reviewing!

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