diff --git a/src/libexpr/eval.hh b/src/libexpr/eval.hh
index b7dab885f..195cb0db3 100644
--- a/src/libexpr/eval.hh
+++ b/src/libexpr/eval.hh
@@ -8,10 +8,6 @@
 
 #include <map>
 
-#if HAVE_BOEHMGC
-#include <gc/gc_allocator.h>
-#endif
-
 
 namespace nix {
 
diff --git a/src/libexpr/value.hh b/src/libexpr/value.hh
index 048522016..271e6a1b2 100644
--- a/src/libexpr/value.hh
+++ b/src/libexpr/value.hh
@@ -1,7 +1,12 @@
 #pragma once
 
+#include "config.h"
 #include "symbol-table.hh"
 
+#if HAVE_BOEHMGC
+#include <gc/gc_allocator.h>
+#endif
+
 namespace nix {