Add assertion for easy debugging of missing stuff

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54459 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ELFTargetAsmInfo.cpp b/lib/Target/ELFTargetAsmInfo.cpp
index e6a40e7..19e5b01 100644
--- a/lib/Target/ELFTargetAsmInfo.cpp
+++ b/lib/Target/ELFTargetAsmInfo.cpp
@@ -130,6 +130,8 @@
 
   unsigned Size = TD->getABITypeSize(Ty);
   if (Size <= 16) {
+    assert(getCStringSection() && "Should have string section prefix");
+
     // We also need alignment here
     const TargetData *TD = ETM->getTargetData();
     unsigned Align = TD->getPrefTypeAlignment(Ty);