diff --git a/src/libs/3rdparty/botan/build/botan/build.h b/src/libs/3rdparty/botan/build/botan/build.h
index e23eb82fe3f90afb970839bc3eedce8ded6a43d3..ea967d935db50f3fa984df5e3bc5d3b6607e8e7c 100644
--- a/src/libs/3rdparty/botan/build/botan/build.h
+++ b/src/libs/3rdparty/botan/build/botan/build.h
@@ -38,4 +38,11 @@
 #   include "build_unix.h"
 #endif
 
+#ifdef QT_ARCH_I386
+#define BOTAN_TARGET_ARCH_IS_IA32
+#define BOTAN_TARGET_CPU_IS_I686
+#elif defined(QT_ARCH_X86_64)
+#define BOTAN_TARGET_ARCH_IS_AMD64
+#endif
+
 #endif