From d25e59535c603074951941ffb9fe4193a8afba8c Mon Sep 17 00:00:00 2001
From: toaster <rollerorbital@gmail.com>
Date: Sun, 18 Dec 2022 14:37:15 +0000
Subject: [PATCH] Invalidate all instances of the same map across multiple
 cups' `cachedlevels`, so that it DEFINITELY will be assigned to the first cup
 in the linked list in P_InitMapData.

---
 src/deh_soc.c | 29 +++++++++++++++++++++++++----
 1 file changed, 25 insertions(+), 4 deletions(-)

diff --git a/src/deh_soc.c b/src/deh_soc.c
index 5b007d4f9..9f9224ae2 100644
--- a/src/deh_soc.c
+++ b/src/deh_soc.c
@@ -3021,6 +3021,28 @@ void readwipes(MYFILE *f)
 // SRB2KART
 //
 
+static void invalidateacrosscups(UINT16 map)
+{
+	cupheader_t *cup = kartcupheaders;
+	UINT8 i;
+
+	if (map >= nummapheaders)
+		return;
+
+	while (cup)
+	{
+		for (i = 0; i < CUPCACHE_MAX; i++)
+		{
+			if (cup->cachedlevels[i] != map)
+				continue;
+			cup->cachedlevels[i] = NEXTMAP_INVALID;
+		}
+		cup = cup->next;
+	}
+
+	mapheaderinfo[map]->cup = NULL;
+}
+
 void readcupheader(MYFILE *f, cupheader_t *cup)
 {
 	char *s = Z_Malloc(MAXLINELEN, PU_STATIC, NULL);
@@ -3077,8 +3099,7 @@ void readcupheader(MYFILE *f, cupheader_t *cup)
 					cup->levellist[cup->numlevels] = NULL;
 					if (cup->cachedlevels[cup->numlevels] == NEXTMAP_INVALID)
 						continue;
-					mapheaderinfo[cup->cachedlevels[cup->numlevels]]->cup = NULL;
-					cup->cachedlevels[cup->numlevels] = NEXTMAP_INVALID;
+					invalidateacrosscups(cup->cachedlevels[cup->numlevels]);
 				}
 
 				tmp = strtok(word2,",");
@@ -3103,8 +3124,7 @@ void readcupheader(MYFILE *f, cupheader_t *cup)
 					cup->levellist[CUPCACHE_BONUS + cup->numbonus] = NULL;
 					if (cup->cachedlevels[CUPCACHE_BONUS + cup->numbonus] == NEXTMAP_INVALID)
 						continue;
-					mapheaderinfo[cup->cachedlevels[CUPCACHE_BONUS + cup->numbonus]]->cup = NULL;
-					cup->cachedlevels[CUPCACHE_BONUS + cup->numbonus] = NEXTMAP_INVALID;
+					invalidateacrosscups(cup->cachedlevels[CUPCACHE_BONUS + cup->numbonus]);
 				}
 
 				tmp = strtok(word2,",");
@@ -3122,6 +3142,7 @@ void readcupheader(MYFILE *f, cupheader_t *cup)
 			}
 			else if (fastcmp(word, "SPECIALSTAGE"))
 			{
+				invalidateacrosscups(cup->cachedlevels[CUPCACHE_SPECIAL]);
 				Z_Free(cup->levellist[CUPCACHE_SPECIAL]);
 				cup->levellist[CUPCACHE_SPECIAL] = Z_StrDup(word2);
 				cup->cachedlevels[CUPCACHE_SPECIAL] = NEXTMAP_INVALID;