testcase that causes the asmparser to assert

llvm-svn: 30969

llvm/test/Regression/Verifier/2006-10-15-AddrLabel.ll

+; RUN: not llvm-as %s -o /dev/null -f &&
+; RUN: llvm-as %s -o /dev/null -f 2>&1 | grep 'Cannot form'
+
+int %main() {
+         %foo  = call sbyte* %llvm.stacksave()
+         %foop = cast sbyte* %foo to label*
+         %nret = load label* %foop
+         br label %nret;
+}