diff --git a/.travis/install.sh b/.travis/install.sh
index 7c3e9de2908e..9db2743794b4 100755
--- a/.travis/install.sh
+++ b/.travis/install.sh
@@ -35,8 +35,8 @@ if [[ "$(uname -s)" == 'Darwin' ]]; then
             ;;
         pypy)
             brew outdated pyenv || brew upgrade pyenv
-            pyenv install pypy-2.5.1
-            pyenv global pypy-2.5.1
+            pyenv install pypy-2.6.0
+            pyenv global pypy-2.6.0
             ;;
         pypy3)
             brew outdated pyenv || brew upgrade pyenv
diff --git a/src/cryptography/hazmat/bindings/commoncrypto/cf.py b/src/cryptography/hazmat/bindings/commoncrypto/cf.py
index 77d2d7cc20fc..3bd44f65a8ea 100644
--- a/src/cryptography/hazmat/bindings/commoncrypto/cf.py
+++ b/src/cryptography/hazmat/bindings/commoncrypto/cf.py
@@ -62,8 +62,10 @@
 };
 typedef int CFNumberType;
 
-const CFDictionaryKeyCallBacks kCFTypeDictionaryKeyCallBacks;
-const CFDictionaryValueCallBacks kCFTypeDictionaryValueCallBacks;
+/* TODO: these should both be "const", which can be added back once we switch
+   to cffi 1.0's set_source */
+CFDictionaryKeyCallBacks kCFTypeDictionaryKeyCallBacks;
+CFDictionaryValueCallBacks kCFTypeDictionaryValueCallBacks;
 
 const CFBooleanRef kCFBooleanTrue;
 const CFBooleanRef kCFBooleanFalse;