diff --git a/llvm/lib/Target/TargetLibraryInfo.cpp b/llvm/lib/Target/TargetLibraryInfo.cpp
index 3e68fe1..7535620 100644
--- a/llvm/lib/Target/TargetLibraryInfo.cpp
+++ b/llvm/lib/Target/TargetLibraryInfo.cpp
@@ -401,6 +401,31 @@
     TLI.setAvailableWithName(LibFunc::fputs, "fputs$UNIX2003");
   }
 
+  // exp10 and exp10f are not available on OS X until 10.9 and iOS until 7.0
+  // and their names are __exp10 and __exp10f. exp10l is not available on
+  // OS X or iOS.
+  if (T.isMacOSX()) {
+    TLI.setUnavailable(LibFunc::exp10l);
+    if (T.isMacOSXVersionLT(10, 9)) {
+      TLI.setUnavailable(LibFunc::exp10);
+      TLI.setUnavailable(LibFunc::exp10f);
+    } else {
+      TLI.setAvailableWithName(LibFunc::exp10, "__exp10");
+      TLI.setAvailableWithName(LibFunc::exp10f, "__exp10f");
+    }
+  }
+
+  if (T.getOS() == Triple::IOS) {
+    TLI.setUnavailable(LibFunc::exp10l);
+    if (T.isOSVersionLT(7, 0)) {
+      TLI.setUnavailable(LibFunc::exp10);
+      TLI.setUnavailable(LibFunc::exp10f);
+    } else {
+      TLI.setAvailableWithName(LibFunc::exp10, "__exp10");
+      TLI.setAvailableWithName(LibFunc::exp10f, "__exp10f");
+    }
+  }
+
   // iprintf and friends are only available on XCore and TCE.
   if (T.getArch() != Triple::xcore && T.getArch() != Triple::tce) {
     TLI.setUnavailable(LibFunc::iprintf);