diff --git a/ConflictSet.cpp b/ConflictSet.cpp
index ddba01a..619b6fc 100644
--- a/ConflictSet.cpp
+++ b/ConflictSet.cpp
@@ -2919,12 +2919,6 @@ Node *firstGeqPhysical(Node *n, const std::span<const uint8_t> key) {
 #define PRESERVE_NONE
 #endif
 
-#if __has_attribute(flatten)
-#define FLATTEN __attribute__((flatten))
-#else
-#define FLATTEN
-#endif
-
 typedef PRESERVE_NONE void (*Continuation)(struct CheckJob *,
                                            struct CheckContext *);
 
@@ -2968,7 +2962,7 @@ struct CheckContext {
 #endif
 };
 
-FLATTEN PRESERVE_NONE void keepGoing(CheckJob *job, CheckContext *context) {
+PRESERVE_NONE void keepGoing(CheckJob *job, CheckContext *context) {
 #if __has_attribute(musttail)
   job = job->next;
   MUSTTAIL return job->continuation(job, context);
@@ -2978,7 +2972,7 @@ FLATTEN PRESERVE_NONE void keepGoing(CheckJob *job, CheckContext *context) {
 #endif
 }
 
-FLATTEN PRESERVE_NONE void complete(CheckJob *job, CheckContext *context) {
+PRESERVE_NONE void complete(CheckJob *job, CheckContext *context) {
   if (context->started == context->count) {
     if (job->prev == job) {
 #if !__has_attribute(musttail)
@@ -2999,12 +2993,11 @@ FLATTEN PRESERVE_NONE void complete(CheckJob *job, CheckContext *context) {
 
 namespace check_point_read_state_machine {
 
-FLATTEN PRESERVE_NONE void begin(CheckJob *, CheckContext *);
+PRESERVE_NONE void begin(CheckJob *, CheckContext *);
 
-template <class NodeT>
-FLATTEN PRESERVE_NONE void iter(CheckJob *, CheckContext *);
+template <class NodeT> PRESERVE_NONE void iter(CheckJob *, CheckContext *);
 
-FLATTEN PRESERVE_NONE void down_left_spine(CheckJob *, CheckContext *);
+PRESERVE_NONE void down_left_spine(CheckJob *, CheckContext *);
 
 static Continuation iterTable[] = {iter<Node0>, iter<Node3>, iter<Node16>,
                                    iter<Node48>, iter<Node256>};
@@ -3132,12 +3125,11 @@ void down_left_spine(CheckJob *job, CheckContext *context) {
 
 namespace check_prefix_read_state_machine {
 
-FLATTEN PRESERVE_NONE void begin(CheckJob *, CheckContext *);
+PRESERVE_NONE void begin(CheckJob *, CheckContext *);
 
-template <class NodeT>
-FLATTEN PRESERVE_NONE void iter(CheckJob *, CheckContext *);
+template <class NodeT> PRESERVE_NONE void iter(CheckJob *, CheckContext *);
 
-FLATTEN PRESERVE_NONE void down_left_spine(CheckJob *, CheckContext *);
+PRESERVE_NONE void down_left_spine(CheckJob *, CheckContext *);
 
 static Continuation iterTable[] = {iter<Node0>, iter<Node3>, iter<Node16>,
                                    iter<Node48>, iter<Node256>};
@@ -3259,12 +3251,12 @@ void down_left_spine(CheckJob *job, CheckContext *context) {
 } // namespace check_prefix_read_state_machine
 
 namespace check_range_read_state_machine {
-FLATTEN PRESERVE_NONE void begin(CheckJob *, CheckContext *);
+PRESERVE_NONE void begin(CheckJob *, CheckContext *);
 
 template <class NodeT>
-FLATTEN PRESERVE_NONE void common_prefix_iter(CheckJob *, CheckContext *);
+PRESERVE_NONE void common_prefix_iter(CheckJob *, CheckContext *);
 
-FLATTEN PRESERVE_NONE void done_common_prefix_iter(CheckJob *, CheckContext *);
+PRESERVE_NONE void done_common_prefix_iter(CheckJob *, CheckContext *);
 
 static Continuation commonPrefixIterTable[] = {
     common_prefix_iter<Node0>, common_prefix_iter<Node3>,
@@ -3272,18 +3264,17 @@ static Continuation commonPrefixIterTable[] = {
     common_prefix_iter<Node256>};
 
 template <class NodeT>
-FLATTEN PRESERVE_NONE void left_side_iter(CheckJob *, CheckContext *);
+PRESERVE_NONE void left_side_iter(CheckJob *, CheckContext *);
 
-FLATTEN PRESERVE_NONE void left_side_down_left_spine(CheckJob *,
-                                                     CheckContext *);
+PRESERVE_NONE void left_side_down_left_spine(CheckJob *, CheckContext *);
 
-FLATTEN PRESERVE_NONE void done_left_side_iter(CheckJob *, CheckContext *);
+PRESERVE_NONE void done_left_side_iter(CheckJob *, CheckContext *);
 
 static Continuation leftSideIterTable[] = {
     left_side_iter<Node0>, left_side_iter<Node3>, left_side_iter<Node16>,
     left_side_iter<Node48>, left_side_iter<Node256>};
 
-FLATTEN PRESERVE_NONE void begin(CheckJob *job, CheckContext *context) {
+PRESERVE_NONE void begin(CheckJob *job, CheckContext *context) {
   job->lcp = longestCommonPrefix(job->begin.data(), job->end.data(),
                                  std::min(job->begin.size(), job->end.size()));
   if (job->lcp == int(job->begin.size()) &&
@@ -3355,8 +3346,8 @@ void common_prefix_iter(CheckJob *job, CheckContext *context) {
   MUSTTAIL return keepGoing(job, context);
 }
 
-FLATTEN PRESERVE_NONE void done_common_prefix_iter(CheckJob *job,
-                                                   CheckContext *context) {
+PRESERVE_NONE void done_common_prefix_iter(CheckJob *job,
+                                           CheckContext *context) {
 
   {
     Arena arena;
@@ -3454,8 +3445,7 @@ FLATTEN PRESERVE_NONE void done_common_prefix_iter(CheckJob *job,
 // Return true if the max version among all keys that start with key[:prefixLen]
 // that are >= key is <= readVersion
 template <class NodeT>
-FLATTEN PRESERVE_NONE void left_side_iter(CheckJob *job,
-                                          CheckContext *context) {
+PRESERVE_NONE void left_side_iter(CheckJob *job, CheckContext *context) {
   assert(NodeT::kType == job->n->getType());
   NodeT *n = static_cast<NodeT *>(job->n);
 
@@ -3570,8 +3560,7 @@ FLATTEN PRESERVE_NONE void left_side_iter(CheckJob *job,
   MUSTTAIL return keepGoing(job, context);
 }
 
-FLATTEN PRESERVE_NONE void done_left_side_iter(CheckJob *job,
-                                               CheckContext *context) {
+PRESERVE_NONE void done_left_side_iter(CheckJob *job, CheckContext *context) {
 
   job->setResult(checkRangeRightSide(job->commonPrefixNode, job->end,
                                      job->lcp + 1, job->readVersion,