diff --git a/pkgs/development/compilers/llvm/4/clang/default.nix b/pkgs/development/compilers/llvm/4/clang/default.nix
index 77863ab4f1ea..28eb118e00df 100644
--- a/pkgs/development/compilers/llvm/4/clang/default.nix
+++ b/pkgs/development/compilers/llvm/4/clang/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetch, cmake, libxml2, libedit, llvm, version, release_version, clang-tools-extra_src, python
+{ stdenv, fetch, cmake, libxml2, libedit, llvm, version, release_version, clang-tools-extra_src, python3
 , fixDarwinDylibNames
 , enableManpages ? false
 }:
@@ -16,8 +16,8 @@ let
       mv clang-tools-extra-* $sourceRoot/tools/extra
     '';
 
-    nativeBuildInputs = [ cmake python ]
-      ++ stdenv.lib.optional enableManpages python.pkgs.sphinx;
+    nativeBuildInputs = [ cmake python3 ]
+      ++ stdenv.lib.optional enableManpages python3.pkgs.sphinx;
 
     buildInputs = [ libedit libxml2 llvm ]
       ++ stdenv.lib.optional stdenv.isDarwin fixDarwinDylibNames;
diff --git a/pkgs/development/compilers/llvm/5/clang/default.nix b/pkgs/development/compilers/llvm/5/clang/default.nix
index c8eafce4e396..a0d61e7a3c9e 100644
--- a/pkgs/development/compilers/llvm/5/clang/default.nix
+++ b/pkgs/development/compilers/llvm/5/clang/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetch, cmake, libxml2, libedit, llvm, version, release_version, clang-tools-extra_src, python
+{ stdenv, fetch, cmake, libxml2, libedit, llvm, version, release_version, clang-tools-extra_src, python3
 , fixDarwinDylibNames
 , enableManpages ? false
 }:
@@ -16,8 +16,8 @@ let
       mv clang-tools-extra-* $sourceRoot/tools/extra
     '';
 
-    nativeBuildInputs = [ cmake python ]
-      ++ stdenv.lib.optional enableManpages python.pkgs.sphinx;
+    nativeBuildInputs = [ cmake python3 ]
+      ++ stdenv.lib.optional enableManpages python3.pkgs.sphinx;
 
     buildInputs = [ libedit libxml2 llvm ]
       ++ stdenv.lib.optional stdenv.isDarwin fixDarwinDylibNames;