diff --git a/llvm/lib/Analysis/TargetLibraryInfo.cpp b/llvm/lib/Analysis/TargetLibraryInfo.cpp
--- a/llvm/lib/Analysis/TargetLibraryInfo.cpp
+++ b/llvm/lib/Analysis/TargetLibraryInfo.cpp
@@ -589,6 +589,11 @@
     TLI.setAvailable(LibFunc_fgets_unlocked);
   }
 
+  if (T.isAndroid() && T.isAndroidVersionLT(21)) {
+    TLI.setUnavailable(LibFunc_stpcpy);
+    TLI.setUnavailable(LibFunc_stpncpy);
+  }
+
   // As currently implemented in clang, NVPTX code has no standard library to
   // speak of.  Headers provide a standard-ish library implementation, but many
   // of the signatures are wrong -- for example, many libm functions are not