From a2ff9423a1ecc4f2831a69f82a60f00c4a3f81a9 Mon Sep 17 00:00:00 2001
From: Peter Zhu <peter@peterzhu.ca>
Date: Mon, 27 Mar 2023 09:40:24 -0400
Subject: [PATCH] Allow user defined SIZE_POOL_COUNT

We shouldn't overwrite the value of SIZE_POOL_COUNT if the user has
specified one.
---
 internal/gc.h | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/internal/gc.h b/internal/gc.h
index 0abdb22ffd..2b67ca40dc 100644
--- a/internal/gc.h
+++ b/internal/gc.h
@@ -189,10 +189,12 @@ struct rb_objspace; /* in vm_core.h */
 
 // We use SIZE_POOL_COUNT number of shape IDs for transitions out of different size pools
 // The next available shape ID will be the SPECIAL_CONST_SHAPE_ID
-#if USE_RVARGC && (SIZEOF_UINT64_T == SIZEOF_VALUE)
-# define SIZE_POOL_COUNT 5
-#else
-# define SIZE_POOL_COUNT 1
+#ifndef SIZE_POOL_COUNT
+# if USE_RVARGC && (SIZEOF_UINT64_T == SIZEOF_VALUE)
+#  define SIZE_POOL_COUNT 5
+# else
+#  define SIZE_POOL_COUNT 1
+# endif
 #endif
 
 #define RCLASS_EXT_EMBEDDED (SIZE_POOL_COUNT > 1)