From 42fd1b9abe90c301632c9279fd29ec6650243430 Mon Sep 17 00:00:00 2001
From: Sergey Sharybin <sergey.vfx@gmail.com>
Date: Mon, 25 Apr 2016 13:50:27 +0200
Subject: [PATCH] Cycles: Fix issues with stack allocator in MSVC

Couple of issues here:

- Was a bug in heap memory allocation when run out
  of allowed stack memory.

- Debug MSVC was failing because it uses separate
  allocator for some sort of internal proxy thing,
  which seems to be unable to be using stack memory
  because allocator is being created in non-persistent
  stack location.
---
 intern/cycles/util/util_stack_allocator.h | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/intern/cycles/util/util_stack_allocator.h b/intern/cycles/util/util_stack_allocator.h
index 1acd2b18bc7..d7aab5b250c 100644
--- a/intern/cycles/util/util_stack_allocator.h
+++ b/intern/cycles/util/util_stack_allocator.h
@@ -40,14 +40,17 @@ public:
 	/* Allocator construction/destruction. */
 
 	StackAllocator()
-	: pointer_(0) {}
+	: pointer_(0),
+	  use_stack_(true) {}
 
 	StackAllocator(const StackAllocator&)
-	: pointer_(0) {}
+	: pointer_(0),
+	  use_stack_(true) {}
 
 	template <class U>
 	StackAllocator(const StackAllocator<SIZE, U>&)
-	: pointer_(0) {}
+	: pointer_(0),
+	  use_stack_(false) {}
 
 	/* Memory allocation/deallocation. */
 
@@ -57,7 +60,7 @@ public:
 		if(n == 0) {
 			return NULL;
 		}
-		if(pointer_ + n >= SIZE) {
+		if(pointer_ + n >= SIZE || use_stack_ == false) {
 			size_t size = n * sizeof(T);
 			util_guarded_mem_alloc(size);
 			T *mem;
@@ -69,6 +72,7 @@ public:
 			if(mem == NULL) {
 				throw std::bad_alloc();
 			}
+			return mem;
 		}
 		T *mem = &data_[pointer_];
 		pointer_ += n;
@@ -157,6 +161,7 @@ public:
 
 private:
 	int pointer_;
+	bool use_stack_;
 	T data_[SIZE];
 };