[PATCH] [core] add support to resolve section groups.

[Shankar Kalpathi Easwaran]

================
Comment at: lib/Core/Resolver.cpp:219
@@ +218,3 @@
+    // for the first time
+    if (isFirstTime) {
+      for (const Reference *r : atom) {
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Rui Ueyama wrote:
> Shankar Kalpathi Easwaran wrote:
> > Rui Ueyama wrote:
> > > Is this the correct semantics? If it's not a COMDAT group, we have to report an error for duplicate section group, no?
> > No. The typeGroupComdat atom has the list of all group child members. 
> Yes, that's I know. But I don't think that answers my comment, I guess. Can you elaborate, please?
Section groups are meant to be resolved in a way that which ever group appears first gets selected by the resolver. The second group just gets ignored. The kindGroupComdat atom models only the signature of the group. I If the symbol was non-COMDAT line 233 handles it as a regular symbol, which would detect whether the symbol was a duplicate symbol or not. 




http://llvm-reviews.chandlerc.com/D3182