Assert that the AddrDelta expression is really constant and wrap it in a set
if we have a lame assembler.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122446 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp
index bff8836..3fd0c53 100644
--- a/lib/MC/MCAssembler.cpp
+++ b/lib/MC/MCAssembler.cpp
@@ -687,7 +687,9 @@
 				     MCDwarfLineAddrFragment &DF) {
   int64_t AddrDelta = 0;
   uint64_t OldSize = DF.getContents().size();
-  DF.getAddrDelta().EvaluateAsAbsolute(AddrDelta, Layout);
+  bool IsAbs = DF.getAddrDelta().EvaluateAsAbsolute(AddrDelta, Layout);
+  (void)IsAbs;
+  assert(IsAbs);
   int64_t LineDelta;
   LineDelta = DF.getLineDelta();
   SmallString<8> &Data = DF.getContents();