Re: new runtime pseudo-reloc in cygwin 1.3.18

[Charles Wilson <cwilson at ece dot gatech dot edu>]

Alexander Gottwald wrote:
> and lib/font/Xfont-def.cpp was missing. I generated the file and attached it 
> to this mail. Maybe we can remove these dependencies. Or do we still need 
> these files, even with autoimport?
It's really a case of whether auto-*export* is working.  As is, ld will 
automatically export all symbols, unless:
  1) you explicitly specify a .def file, or
  2) ANY of your object files contain ANY symbol that is *already* 
marked with __declspec(dllexport).  In that case, ld figures that 
you'd've marked every symbol you want to export and won't automatically 
add anything to the export list.

2) sometimes leads to non-intuitive behavior (e.g. glib, where Tor 
explicitly marked ONLY those symbols that were multi-word data items -- 
that is, where runtime-pseudo-relocs would be used in newer ld's -- and 
thus, ONLY those five symbols get exported, unless a .def file is used. 
 Which is way more difficult to do with libtool than it should be.  Sigh.

If either 1) or 2) is true, but you WANT additional exports, you can either

a) explicitly specify --export-all-symbols on the link line
b) create and use a .def file if you were not previously doing so, or 
add the additional symbols to the .def file if you were already using one.

So, the question is: "Is any symbol in the XFree86 codebase explicitly 
marked with __declspec(dllexport) when compiled for cygwin?"  YES: then 
you DO need to keep the .def file (and note that ld is sensitive to 
whether the filename ends in ".def") or you must explicitly specify 
"--export-all-symbols" on the link line.  NO: then the .def file can be 
discarded, and you can rely on the implicit export-all-symbols behavior 
(unless you want to restrict the export list to some subset of "all 
symbols").

(Oh, and the .def file does give you the in-built LIBRARY VERSION 
string...if that's important)

> But some programs (xedit, viewres, xmessage) report an runtime error
> Error: Unresolved inheritance operation
Dunno about this.

--Chuck