diff --git a/ir/memory.cpp b/ir/memory.cpp
index d9959c9aa..6e7ba323d 100644
--- a/ir/memory.cpp
+++ b/ir/memory.cpp
@@ -918,9 +918,9 @@ Memory::AliasSet Memory::computeAliasing(const Pointer &ptr, unsigned bytes,
   return aliasing;
 }
 
-template <typename Fn>
 void Memory::access(const Pointer &ptr, unsigned bytes, uint64_t align,
-                    bool write, Fn &fn) {
+                    bool write, const
+                      function<void(MemBlock&, unsigned, bool, expr&&)> &fn) {
   auto aliasing = computeAliasing(ptr, bytes, align, write);
   unsigned has_local = aliasing.numMayAlias(true);
   unsigned has_nonlocal = aliasing.numMayAlias(false);
@@ -972,12 +972,12 @@ vector<Byte> Memory::load(const Pointer &ptr, unsigned bytes, set<expr> &undef,
   expr offset = ptr.getShortOffset();
   unsigned off_bits = Pointer::bitsShortOffset();
 
-  auto fn = [&](const MemBlock &blk, unsigned bid, bool local, expr &&cond) {
+  auto fn = [&](MemBlock &blk, unsigned bid, bool local, expr &&cond) {
     bool is_poison = (type & blk.type) == DATA_NONE;
     for (unsigned i = 0; i < loaded_bytes; ++i) {
       unsigned idx = left2right ? i : (loaded_bytes - i - 1);
       expr off = offset + expr::mkUInt(idx, off_bits);
-      loaded[i].add(is_poison ? poison : blk.val.load(off), std::move(cond));
+      loaded[i].add(is_poison ? poison : blk.val.load(off), cond);
       if (!is_poison)
         undef.insert(blk.undef.begin(), blk.undef.end());
     }
diff --git a/ir/memory.h b/ir/memory.h
index d04e0bc70..256975282 100644
--- a/ir/memory.h
+++ b/ir/memory.h
@@ -179,9 +179,9 @@ class Memory {
   AliasSet computeAliasing(const Pointer &ptr, unsigned bytes, uint64_t align,
                            bool write) const;
 
-  template <typename Fn>
   void access(const Pointer &ptr, unsigned btyes, uint64_t align, bool write,
-              Fn &fn);
+              const std::function<void(MemBlock&, unsigned, bool,
+                                       smt::expr&&)> &fn);
 
   std::vector<Byte> load(const Pointer &ptr, unsigned bytes,
                          std::set<smt::expr> &undef, uint64_t align,