diff --git a/src/amount.cc b/src/amount.cc
index 591b0901..6e0af790 100644
--- a/src/amount.cc
+++ b/src/amount.cc
@@ -43,6 +43,9 @@
 
 #include "amount.h"
 #include "binary.h"
+#ifdef HAVE_GDTOA
+#include "gdtoa.h"
+#endif
 
 namespace ledger {