diff --git a/src/pal/pal_open_enclave.h b/src/pal/pal_open_enclave.h
index 5e37e0438..f8124f57f 100644
--- a/src/pal/pal_open_enclave.h
+++ b/src/pal/pal_open_enclave.h
@@ -3,8 +3,6 @@
 #include "ds/address.h"
 #include "pal_plain.h"
 #ifdef OPEN_ENCLAVE
-extern "C" const void* __oe_get_heap_base();
-extern "C" const void* __oe_get_heap_end();
 extern "C" void* oe_memset_s(void* p, size_t p_size, int c, size_t size);
 extern "C" [[noreturn]] void oe_abort();
 
@@ -12,9 +10,19 @@ namespace snmalloc
 {
   class PALOpenEnclave
   {
-    std::atomic<void*> oe_base = nullptr;
+    static inline std::atomic<void*> oe_base;
+    static inline void* oe_end = nullptr;
 
   public:
+    /**
+     * This will be called by oe_allocator_init to set up enclave heap bounds.
+     */
+    static void setup_initial_range(void* base, void* end)
+    {
+      oe_base = base;
+      oe_end = end;
+    }
+
     /**
      * Bitmap of PalFeatures flags indicating the optional features that this
      * PAL supports.
@@ -32,17 +40,9 @@ namespace snmalloc
     template<bool committed>
     void* reserve(size_t size) noexcept
     {
-      if (oe_base == 0)
-      {
-        void* dummy = NULL;
-        // If this CAS fails then another thread has initialised this.
-        oe_base.compare_exchange_strong(
-          dummy, const_cast<void*>(__oe_get_heap_base()));
-      }
-
       void* old_base = oe_base;
       void* next_base;
-      auto end = __oe_get_heap_end();
+      auto end = oe_end;
       do
       {
         auto new_base = old_base;
diff --git a/src/test/func/fixed_region/fixed_region.cc b/src/test/func/fixed_region/fixed_region.cc
index 6c9679780..4f64700b2 100644
--- a/src/test/func/fixed_region/fixed_region.cc
+++ b/src/test/func/fixed_region/fixed_region.cc
@@ -10,18 +10,6 @@
 #endif
 #define assert please_use_SNMALLOC_ASSERT
 
-void* oe_base;
-void* oe_end;
-extern "C" const void* __oe_get_heap_base()
-{
-  return oe_base;
-}
-
-extern "C" const void* __oe_get_heap_end()
-{
-  return oe_end;
-}
-
 extern "C" void* oe_memset_s(void* p, size_t p_size, int c, size_t size)
 {
   UNUSED(p_size);
@@ -43,8 +31,9 @@ int main()
   // For 1MiB superslabs, SUPERSLAB_BITS + 4 is not big enough for the example.
   size_t large_class = 28 - SUPERSLAB_BITS;
   size_t size = 1ULL << (SUPERSLAB_BITS + large_class);
-  oe_base = mp.reserve<true>(large_class);
-  oe_end = (uint8_t*)oe_base + size;
+  void* oe_base = mp.reserve<true>(large_class);
+  void* oe_end = (uint8_t*)oe_base + size;
+  PALOpenEnclave::setup_initial_range(oe_base, oe_end);
   std::cout << "Allocated region " << oe_base << " - " << oe_end << std::endl;
 
   auto a = ThreadAlloc::get();
diff --git a/src/test/func/two_alloc_types/alloc1.cc b/src/test/func/two_alloc_types/alloc1.cc
index c86dcde02..f6966005f 100644
--- a/src/test/func/two_alloc_types/alloc1.cc
+++ b/src/test/func/two_alloc_types/alloc1.cc
@@ -9,3 +9,8 @@
 // Redefine the namespace, so we can have two versions.
 #define snmalloc snmalloc_enclave
 #include "../../../override/malloc.cc"
+
+extern "C" void oe_allocator_init(void* base, void* end)
+{
+  snmalloc_enclave::PALOpenEnclave::setup_initial_range(base, end);
+}
diff --git a/src/test/func/two_alloc_types/main.cc b/src/test/func/two_alloc_types/main.cc
index 341f32dc7..1ef9d1cd1 100644
--- a/src/test/func/two_alloc_types/main.cc
+++ b/src/test/func/two_alloc_types/main.cc
@@ -5,18 +5,6 @@
 #include <string.h>
 #include <test/setup.h>
 
-void* oe_base;
-void* oe_end;
-extern "C" const void* __oe_get_heap_base()
-{
-  return oe_base;
-}
-
-extern "C" const void* __oe_get_heap_end()
-{
-  return oe_end;
-}
-
 extern "C" void* oe_memset_s(void* p, size_t p_size, int c, size_t size)
 {
   UNUSED(p_size);
@@ -28,6 +16,7 @@ extern "C" void oe_abort()
   abort();
 }
 
+extern "C" void oe_allocator_init(void* base, void* end);
 extern "C" void* host_malloc(size_t);
 extern "C" void host_free(void*);
 
@@ -51,8 +40,9 @@ int main()
   // For 1MiB superslabs, SUPERSLAB_BITS + 2 is not big enough for the example.
   size_t large_class = 26 - SUPERSLAB_BITS;
   size_t size = 1ULL << (SUPERSLAB_BITS + large_class);
-  oe_base = mp.reserve<true>(large_class);
-  oe_end = (uint8_t*)oe_base + size;
+  void* oe_base = mp.reserve<true>(large_class);
+  void* oe_end = (uint8_t*)oe_base + size;
+  oe_allocator_init(oe_base, oe_end);
   std::cout << "Allocated region " << oe_base << " - " << oe_end << std::endl;
 
   // Call these functions to trigger asserts if the cast-to-self doesn't work.