From 1197117258e720aab8d599f8ea9f26ba00f95dd3 Mon Sep 17 00:00:00 2001
From: Andrew Noyes <andrew@weaselab.dev>
Date: Mon, 12 May 2025 23:15:46 -0400
Subject: [PATCH] Add PRESERVE_NONE

---
 src/test.cpp | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/src/test.cpp b/src/test.cpp
index d00a7c3..ab16594 100644
--- a/src/test.cpp
+++ b/src/test.cpp
@@ -415,6 +415,12 @@ private:
 #define MUSTTAIL
 #endif
 
+#if __has_attribute(preserve_none)
+#define PRESERVE_NONE __attribute__((preserve_none))
+#else
+#define PRESERVE_NONE
+#endif
+
 struct Parser2 {
   Parser2(char *buf, int len, const Callbacks *callbacks, void *data)
       : buf(buf), len(len), callbacks(callbacks), data(data) {}
@@ -489,7 +495,7 @@ private:
     return true;
   }
 
-  typedef bool (*continuation)(Parser2 *);
+  typedef PRESERVE_NONE bool (*continuation)(Parser2 *);
 
   void printStack() {
     printf("token: %s\n", symbolNames[currentToken]);
@@ -499,7 +505,7 @@ private:
     printf("\n");
   }
 
-  static bool keepGoing(Parser2 *self) {
+  PRESERVE_NONE static bool keepGoing(Parser2 *self) {
     // self->printStack();
     if (self->stack.empty()) {
       assert(self->currentToken == T_EOF);
@@ -518,8 +524,8 @@ private:
         self);
   }
 
-  static bool reject(Parser2 *) { return false; }
-  static bool object(Parser2 *self) {
+  PRESERVE_NONE static bool reject(Parser2 *) { return false; }
+  PRESERVE_NONE static bool object(Parser2 *self) {
     assert(self->currentToken == T_LBRACE);
     self->callbacks->on_begin_object(self->data);
     self->nextToken();
@@ -530,7 +536,7 @@ private:
     self->stack.push_back(T_STRING);
     MUSTTAIL return keepGoing(self);
   }
-  static bool atom(Parser2 *self) {
+  PRESERVE_NONE static bool atom(Parser2 *self) {
     if (*self->bufBefore == 't') {
       self->callbacks->on_true_literal(self->data);
     } else if (*self->bufBefore == 'f') {
@@ -547,13 +553,13 @@ private:
     self->stack.pop_back();
     MUSTTAIL return keepGoing(self);
   }
-  static bool string(Parser2 *self) {
+  PRESERVE_NONE static bool string(Parser2 *self) {
     assert(self->currentToken == T_STRING);
     self->nextToken();
     self->stack.pop_back();
     MUSTTAIL return keepGoing(self);
   }
-  static bool array(Parser2 *self) {
+  PRESERVE_NONE static bool array(Parser2 *self) {
     assert(self->currentToken == T_LBRACKET);
     self->callbacks->on_begin_array(self->data);
     self->nextToken();
@@ -562,7 +568,7 @@ private:
     self->stack.push_back(N_VALUE);
     MUSTTAIL return keepGoing(self);
   }
-  static bool continueArray(Parser2 *self) {
+  PRESERVE_NONE static bool continueArray(Parser2 *self) {
     assert(self->currentToken == T_COMMA);
     self->nextToken();
     self->stack.pop_back();
@@ -570,7 +576,7 @@ private:
     self->stack.push_back(N_VALUE);
     MUSTTAIL return keepGoing(self);
   }
-  static bool continueObject(Parser2 *self) {
+  PRESERVE_NONE static bool continueObject(Parser2 *self) {
     assert(self->currentToken == T_COMMA);
     self->nextToken();
     self->stack.pop_back();
@@ -580,14 +586,14 @@ private:
     self->stack.push_back(T_STRING);
     MUSTTAIL return keepGoing(self);
   }
-  static bool finishArray(Parser2 *self) {
+  PRESERVE_NONE static bool finishArray(Parser2 *self) {
     assert(self->currentToken == T_RBRACKET);
     self->callbacks->on_end_array(self->data);
     self->nextToken();
     self->stack.pop_back();
     MUSTTAIL return keepGoing(self);
   }
-  static bool finishObject(Parser2 *self) {
+  PRESERVE_NONE static bool finishObject(Parser2 *self) {
     assert(self->currentToken == T_RBRACE);
     self->callbacks->on_end_object(self->data);
     self->nextToken();