diff --git a/src/alire/os_windows/alire-platforms-current__windows.adb b/src/alire/os_windows/alire-platforms-current__windows.adb
index 3b4e892ac..d56796f4c 100644
--- a/src/alire/os_windows/alire-platforms-current__windows.adb
+++ b/src/alire/os_windows/alire-platforms-current__windows.adb
@@ -132,6 +132,8 @@ package body Alire.Platforms.Current is
 
                Ctx.Append ("C_INCLUDE_PATH", Root / "mingw64" / "include",
                            "msys2");
+               Ctx.Append ("CPLUS_INCLUDE_PATH", Root / "mingw64" / "include",
+                           "msys2");
             end;
 
          when others =>