From cf70cb70bcd5292ed10d8fb08019f0da82db25dd Mon Sep 17 00:00:00 2001
From: Thomas Schatzl <tschatzl@openjdk.org>
Date: Thu, 21 Aug 2025 15:32:25 +0000
Subject: [PATCH] 8365024: G1: Make G1CollectionSet::_inc_build_state
 assert-only

Reviewed-by: ayang, kbarrett
---
 src/hotspot/share/gc/g1/g1CollectionSet.cpp | 6 +++---
 src/hotspot/share/gc/g1/g1CollectionSet.hpp | 2 ++
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/hotspot/share/gc/g1/g1CollectionSet.cpp b/src/hotspot/share/gc/g1/g1CollectionSet.cpp
index 804ded144bd..6fbbeb41a82 100644
--- a/src/hotspot/share/gc/g1/g1CollectionSet.cpp
+++ b/src/hotspot/share/gc/g1/g1CollectionSet.cpp
@@ -67,7 +67,7 @@ G1CollectionSet::G1CollectionSet(G1CollectedHeap* g1h, G1Policy* policy) :
   _survivor_region_length(0),
   _initial_old_region_length(0),
   _optional_groups(),
-  _inc_build_state(CSetBuildType::Inactive),
+  DEBUG_ONLY(_inc_build_state(CSetBuildType::Inactive) COMMA)
   _regions_inc_part_start(0),
   _groups_inc_part_start(0) {
 }
@@ -142,11 +142,11 @@ void G1CollectionSet::continue_incremental_building() {
   _regions_inc_part_start = _regions_cur_length;
   _groups_inc_part_start = groups_cur_length();
 
-  _inc_build_state = CSetBuildType::Active;
+  DEBUG_ONLY(_inc_build_state = CSetBuildType::Active;)
 }
 
 void G1CollectionSet::stop_incremental_building() {
-  _inc_build_state = CSetBuildType::Inactive;
+  DEBUG_ONLY(_inc_build_state = CSetBuildType::Inactive;)
 }
 
 void G1CollectionSet::clear() {
diff --git a/src/hotspot/share/gc/g1/g1CollectionSet.hpp b/src/hotspot/share/gc/g1/g1CollectionSet.hpp
index 2bde960fbc4..7038cd4e677 100644
--- a/src/hotspot/share/gc/g1/g1CollectionSet.hpp
+++ b/src/hotspot/share/gc/g1/g1CollectionSet.hpp
@@ -165,12 +165,14 @@ class G1CollectionSet {
   // groups. Regions are reachable via this list as well.
   G1CSetCandidateGroupList _optional_groups;
 
+#ifdef ASSERT
   enum class CSetBuildType {
     Active,             // We are actively building the collection set
     Inactive            // We are not actively building the collection set
   };
 
   CSetBuildType _inc_build_state;
+#endif
   // Index into the _regions indicating the start of the current collection set increment.
   size_t _regions_inc_part_start;
   // Index into the _groups indicating the start of the current collection set increment.