[PATCH] [PECOFF] Support COMDAT associative sections.

[Simon Atanasyan]

LGTM with minor question / note.

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Comment at: lib/ReaderWriter/PECOFF/ReaderCOFF.cpp:174
@@ +173,3 @@
+  // COMDAT associative sections
+  std::map<const coff_section *, std::set<const coff_section *>> _association;
+
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Is it really necessary to use the `std::set` here i.e. is it possible that a COFF file contains more than one "record" states that sections say "A" and "B" are associated?

http://reviews.llvm.org/D3946