From 4b63c76861647332f0d18e9af360917cbc166182 Mon Sep 17 00:00:00 2001
From: Daan <daanl@outlook.com>
Date: Mon, 10 Jan 2022 11:40:36 -0800
Subject: [PATCH 1/2] avoid conditional load on macos

---
 include/mimalloc-internal.h | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/include/mimalloc-internal.h b/include/mimalloc-internal.h
index 5f016640..3da9a0c8 100644
--- a/include/mimalloc-internal.h
+++ b/include/mimalloc-internal.h
@@ -154,8 +154,8 @@ bool        _mi_page_is_valid(mi_page_t* page);
 // ------------------------------------------------------
 
 #if defined(__GNUC__) || defined(__clang__)
-#define mi_unlikely(x)     __builtin_expect((x),0)
-#define mi_likely(x)       __builtin_expect((x),1)
+#define mi_unlikely(x)     __builtin_expect(!!(x),false)
+#define mi_likely(x)       __builtin_expect(!!(x),true)
 #else
 #define mi_unlikely(x)     (x)
 #define mi_likely(x)       (x)
@@ -346,11 +346,15 @@ extern pthread_key_t _mi_heap_default_key;
 // However, on the Apple M1 we do use the address of this variable as the unique thread-id (issue #356).
 extern mi_decl_thread mi_heap_t* _mi_heap_default;  // default heap to allocate from
 
-
 static inline mi_heap_t* mi_get_default_heap(void) {
 #if defined(MI_TLS_SLOT)
   mi_heap_t* heap = (mi_heap_t*)mi_tls_slot(MI_TLS_SLOT);
-  if (mi_unlikely(heap == NULL)) { heap = (mi_heap_t*)&_mi_heap_empty; } //_mi_heap_empty_get(); }
+  if (mi_unlikely(heap == NULL)) {
+    #ifdef __GNUC__
+    __asm(""); // prevent conditional load of the address of _mi_heap_empty
+    #endif
+    heap = (mi_heap_t*)&_mi_heap_empty;    
+  }
   return heap;
 #elif defined(MI_TLS_PTHREAD_SLOT_OFS)
   mi_heap_t* heap = *mi_tls_pthread_heap_slot();

From deda8bd22b11061a23748750654d1e71b9043652 Mon Sep 17 00:00:00 2001
From: Daan <daanl@outlook.com>
Date: Mon, 10 Jan 2022 11:40:57 -0800
Subject: [PATCH 2/2] fix g++ compilation on macos

---
 src/alloc-override-osx.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/src/alloc-override-osx.c b/src/alloc-override-osx.c
index 63297c4c..af79d64a 100644
--- a/src/alloc-override-osx.c
+++ b/src/alloc-override-osx.c
@@ -200,6 +200,9 @@ static malloc_introspection_t mi_introspect = {
 };
 
 static malloc_zone_t mi_malloc_zone = {
+  // note: even with designators, the order is important for C++ compilation
+  //.reserved1 = NULL,
+  //.reserved2 = NULL,
   .size = &zone_size,
   .malloc = &zone_malloc,
   .calloc = &zone_calloc,
@@ -212,18 +215,20 @@ static malloc_zone_t mi_malloc_zone = {
   .batch_free = &zone_batch_free,
   .introspect = &mi_introspect,  
 #if defined(MAC_OS_X_VERSION_10_6) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_6
+  #if defined(MAC_OS_X_VERSION_10_7) && (MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7)
+  .version = 10,
+  #else
+  .version = 9,
+  #endif
   // switch to version 9+ on OSX 10.6 to support memalign.
   .memalign = &zone_memalign,
   .free_definite_size = &zone_free_definite_size,
   .pressure_relief = &zone_pressure_relief,
-  #if defined(MAC_OS_X_VERSION_10_7) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+  #if defined(MAC_OS_X_VERSION_10_7) && (MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7)
   .claimed_address = &zone_claimed_address,
-  .version = 10
-  #else
-  .version = 9
   #endif
 #else
-  .version = 4
+  .version = 4,
 #endif
 };