Remove an unnecessary cast.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136609 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 1297e10..42d042e 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -880,7 +880,7 @@
          I != E; ++I) {
       MCSymbol *Name = Mang->getSymbol(I);
 
-      const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
+      const GlobalValue *GV = I->getAliasedGlobal();
       MCSymbol *Target = Mang->getSymbol(GV);
 
       if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())