diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index fa7d649ed3f..0887cf084c7 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -4379,8 +4379,6 @@ in modules // {
       substituteInPlace testing/cffi0/test_ownlib.py --replace "gcc" "cc"
     '';
 
-    NIX_CFLAGS_COMPILE="-Wno-shift-negative-value";
-
     checkPhase = ''
       py.test
     '';