[PATCH] Extend acceptable undefined symbol handling

[Shankar Kalpathi Easwaran]

================
Comment at: include/lld/Core/LinkingContext.h:320
@@ +319,3 @@
+  /// Abstract method to return whether the output is shared for the purpose
+  /// of missing undefind symbols.
+  virtual bool outputIsSharedLibrary() const = 0;
----------------
minor not: still says undefind --> undefined.

================
Comment at: lib/Core/Resolver.cpp:342-344
@@ -341,6 +341,5 @@
 
-      // If this is a library and undefined symbols are allowed on the
-      // target platform, skip over it.
-      if (isa<SharedLibraryFile>(f) && _context.allowShlibUndefines())
-        continue;
+      // Ignore undefined symbols from other shared libraries.
+      if (isa<SharedLibraryFile>(f))
+          continue;
 
----------------
Why do we want to ignore undefined symbols from shared libraries with dynamic linking ?

The condition should include 

if (isa<SharedLibraryFile>(f) && !_context.allowShlibUndefines())
continue

or try to combine these conditions in the below condition.


================
Comment at: include/lld/Core/LinkingContext.h:321
@@ -319,1 +320,3 @@
+  /// of missing undefind symbols.
+  virtual bool outputIsSharedLibrary() const = 0;
   /// @}
----------------
minor nit :- Isnt SharedLibrary an ELF term ? If so, should that be changed to Dynamic library or so 


http://llvm-reviews.chandlerc.com/D1582