From b3e5eea4a91400fb2a12aba4b07a94d03ba54605 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Thu, 16 Apr 2020 16:28:07 +0200
Subject: [PATCH] Add function to allocate a Value in traceable memory

---
 src/libexpr/eval.cc  | 8 ++++++++
 src/libexpr/value.hh | 5 +++++
 2 files changed, 13 insertions(+)

diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index f963a42ca..2f5b1db47 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -22,6 +22,8 @@
 
 #if HAVE_BOEHMGC
 
+#define GC_INCLUDE_NEW
+
 #include <gc/gc.h>
 #include <gc/gc_cpp.h>
 
@@ -56,6 +58,12 @@ static char * dupStringWithLen(const char * s, size_t size)
 }
 
 
+RootValue allocRootValue(Value * v)
+{
+    return std::allocate_shared<Value *>(traceable_allocator<Value *>(), v);
+}
+
+
 static void printValue(std::ostream & str, std::set<const Value *> & active, const Value & v)
 {
     checkInterrupt();
diff --git a/src/libexpr/value.hh b/src/libexpr/value.hh
index 689373873..9cf2bf06a 100644
--- a/src/libexpr/value.hh
+++ b/src/libexpr/value.hh
@@ -261,4 +261,9 @@ typedef std::map<Symbol, Value *> ValueMap;
 #endif
 
 
+/* A value allocated in traceable memory. */
+typedef std::shared_ptr<Value *> RootValue;
+
+RootValue allocRootValue(Value * v);
+
 }