From 6ac5dcb1f427bbb99ef1530af0bb122bb302a773 Mon Sep 17 00:00:00 2001
From: Richard Brooksby <rb@ravenbrook.com>
Date: Wed, 8 Mar 2023 11:03:27 +0000
Subject: [PATCH] Declaring variable as static volatile to ensure clean
 communication with debugger and suppress warnings.  this is a better
 expression of intention.

---
 mps/code/amcss.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/mps/code/amcss.c b/mps/code/amcss.c
index 5f7ed999013..2923d6654da 100644
--- a/mps/code/amcss.c
+++ b/mps/code/amcss.c
@@ -95,13 +95,12 @@ static void report(void)
 
 static mps_addr_t make(size_t rootsCount)
 {
-  static unsigned long calls = 0;
+  static volatile unsigned long calls = 0; /* for use from debugger */
   size_t length = rnd() % (scale * avLEN);
   size_t size = (length+2) * sizeof(mps_word_t);
   mps_addr_t p;
   mps_res_t res;
   ++ calls;
-  (void)calls; /* suppress unused warning: we want to look at this from debugger */
 
   do {
     MPS_RESERVE_BLOCK(res, p, ap, size);