diff --git a/pkgs/tools/networking/curl/default.nix b/pkgs/tools/networking/curl/default.nix
index 4a1ff7f1798..5980392267b 100644
--- a/pkgs/tools/networking/curl/default.nix
+++ b/pkgs/tools/networking/curl/default.nix
@@ -76,8 +76,8 @@ stdenv.mkDerivation rec {
     ++ stdenv.lib.optional c-aresSupport "--enable-ares=${c-ares}"
     ++ stdenv.lib.optional gssSupport "--with-gssapi=${kerberos.dev}";
 
-  CXX = "c++";
-  CXXCPP = "c++ -E";
+  CXX = "${stdenv.cc.targetPrefix}c++";
+  CXXCPP = "${stdenv.cc.targetPrefix}c++ -E";
 
   doCheck = false; # expensive, fails