diff --git a/libs/binder/BpBinder.cpp b/libs/binder/BpBinder.cpp
index 8d9955d..589df9a 100644
--- a/libs/binder/BpBinder.cpp
+++ b/libs/binder/BpBinder.cpp
@@ -261,7 +261,7 @@
 
 bool BpBinder::isDescriptorCached() const {
     Mutex::Autolock _l(mLock);
-    return mDescriptorCache.string() != kDescriptorUninit.string();
+    return mDescriptorCache.c_str() != kDescriptorUninit.c_str();
 }
 
 const String16& BpBinder::getInterfaceDescriptor() const
@@ -279,7 +279,7 @@
             Mutex::Autolock _l(mLock);
             // mDescriptorCache could have been assigned while the lock was
             // released.
-            if (mDescriptorCache.string() == kDescriptorUninit.string()) mDescriptorCache = res;
+            if (mDescriptorCache.c_str() == kDescriptorUninit.c_str()) mDescriptorCache = res;
         }
     }