[PATCH] Allow DWARFDebugInfoEntryMinimal::getSubroutineName to resolve cross-unit references.

[Alexey Samsonov]

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Comment at: lib/DebugInfo/DWARFDebugInfoEntry.cpp:31
@@ +30,3 @@
+  Unit = Unit->getUnitSection().getUnitForOffset(*Offset);
+  assert(Unit && "Invalid DIE reference provided.");
+  return DIE.extractFast(Unit, Offset) ? Unit : nullptr;
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If the reference is invalid, just return nullptr

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Comment at: test/DebugInfo/Inputs/cross-cu-inlining.c:1
@@ +1,2 @@
+// a.c -- compile a.c and b.c with lto to generate the binary file
+int i;
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Please provide a better description of how to turn this into an .o file (exact sequence of commands).

http://reviews.llvm.org/D5394