diff --git a/cmake/pcre.cmake b/cmake/pcre.cmake
index 009dbbe5ae1..3d4f163fab9 100644
--- a/cmake/pcre.cmake
+++ b/cmake/pcre.cmake
@@ -43,8 +43,8 @@ MACRO(BUNDLE_PCRE2)
   ExternalProject_Add(
     pcre2
     PREFIX   "${dir}"
-    URL      "http://ftp.pcre.org/pub/pcre/pcre2-10.36.zip"
-    URL_MD5  ba9e743af42aac5642f7504b12af4116
+    URL      "http://ftp.pcre.org/pub/pcre/pcre2-10.37.zip"
+    URL_MD5  8c1699a725d4b28410adf4b964ebbcb7
     INSTALL_COMMAND ""
     CMAKE_ARGS
       "-DPCRE2_BUILD_TESTS=OFF"
diff --git a/mysql-test/main/processlist_notembedded.result b/mysql-test/main/processlist_notembedded.result
index d5c25c0a1d9..26f6e4f9247 100644
--- a/mysql-test/main/processlist_notembedded.result
+++ b/mysql-test/main/processlist_notembedded.result
@@ -28,6 +28,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 Warnings:
 Note	1003	select sleep(100000)
 KILL QUERY $con_id;
+disconnect con1;
 #
 # End of 10.2 tests
 #
diff --git a/mysql-test/main/processlist_notembedded.test b/mysql-test/main/processlist_notembedded.test
index cc577200368..35cac36bb95 100644
--- a/mysql-test/main/processlist_notembedded.test
+++ b/mysql-test/main/processlist_notembedded.test
@@ -1,4 +1,3 @@
-source include/have_debug.inc;
 source include/have_debug_sync.inc;
 source include/not_embedded.inc;
 source include/count_sessions.inc;
@@ -37,8 +36,6 @@ connection default;
 
 SET DEBUG_SYNC = 'RESET';
 
-source include/wait_until_count_sessions.inc;
-
 --echo #
 --echo # End of 5.5 tests
 --echo #
@@ -52,8 +49,12 @@ source include/wait_until_count_sessions.inc;
 --send select sleep(100000)
 
 --connection default
+let $wait_condition= SELECT COUNT(*)=1 FROM information_schema.processlist where state='User sleep';
+source include/wait_condition.inc;
 evalp SHOW EXPLAIN FOR $con_id;
 evalp KILL QUERY $con_id;
+disconnect con1;
+source include/wait_until_count_sessions.inc;
 
 --echo #
 --echo # End of 10.2 tests
diff --git a/mysql-test/suite/gcol/inc/gcol_partition.inc b/mysql-test/suite/gcol/inc/gcol_partition.inc
index 4e4af4f0023..50a743c0153 100644
--- a/mysql-test/suite/gcol/inc/gcol_partition.inc
+++ b/mysql-test/suite/gcol/inc/gcol_partition.inc
@@ -169,3 +169,15 @@ CREATE TABLE t1 (
 INSERT INTO t1 () VALUES (),();
 UPDATE t1 SET a = 0 WHERE b IS NULL ORDER BY pk;
 DROP TABLE t1;
+
+--echo #
+--echo # MDEV-26220 Server crashes with indexed by prefix virtual column
+--echo #
+
+CREATE TABLE t1 (pk INT PRIMARY KEY, a INT, b CHAR(20), c CHAR(20) AS (b),
+                 KEY (c(10),a)) PARTITION BY HASH(pk);
+INSERT INTO t1 (pk,a,b) VALUES (1,10,'foo'),(2,11,'baz');
+SELECT a FROM t1;
+
+# Cleanup
+DROP TABLE t1;
diff --git a/mysql-test/suite/gcol/r/gcol_partition_innodb.result b/mysql-test/suite/gcol/r/gcol_partition_innodb.result
index d3f211c9b9a..e61c0a26417 100644
--- a/mysql-test/suite/gcol/r/gcol_partition_innodb.result
+++ b/mysql-test/suite/gcol/r/gcol_partition_innodb.result
@@ -104,6 +104,17 @@ INSERT INTO t1 () VALUES (),();
 UPDATE t1 SET a = 0 WHERE b IS NULL ORDER BY pk;
 DROP TABLE t1;
 #
+# MDEV-26220 Server crashes with indexed by prefix virtual column
+#
+CREATE TABLE t1 (pk INT PRIMARY KEY, a INT, b CHAR(20), c CHAR(20) AS (b),
+KEY (c(10),a)) PARTITION BY HASH(pk);
+INSERT INTO t1 (pk,a,b) VALUES (1,10,'foo'),(2,11,'baz');
+SELECT a FROM t1;
+a
+11
+10
+DROP TABLE t1;
+#
 # MDEV-16980 Wrongly set tablename len while opening the
 #                table for purge thread
 #
diff --git a/mysql-test/suite/gcol/r/gcol_partition_myisam.result b/mysql-test/suite/gcol/r/gcol_partition_myisam.result
index 75e216f903b..e54b0ad83c6 100644
--- a/mysql-test/suite/gcol/r/gcol_partition_myisam.result
+++ b/mysql-test/suite/gcol/r/gcol_partition_myisam.result
@@ -101,6 +101,17 @@ KEY (b,d)
 INSERT INTO t1 () VALUES (),();
 UPDATE t1 SET a = 0 WHERE b IS NULL ORDER BY pk;
 DROP TABLE t1;
+#
+# MDEV-26220 Server crashes with indexed by prefix virtual column
+#
+CREATE TABLE t1 (pk INT PRIMARY KEY, a INT, b CHAR(20), c CHAR(20) AS (b),
+KEY (c(10),a)) PARTITION BY HASH(pk);
+INSERT INTO t1 (pk,a,b) VALUES (1,10,'foo'),(2,11,'baz');
+SELECT a FROM t1;
+a
+11
+10
+DROP TABLE t1;
 DROP VIEW  IF EXISTS v1,v2;
 DROP TABLE IF EXISTS t1,t2,t3;
 DROP PROCEDURE IF EXISTS p1;
diff --git a/mysql-test/suite/gcol/r/innodb_virtual_index.result b/mysql-test/suite/gcol/r/innodb_virtual_index.result
index 2e9b762500d..aafe65b7fa3 100644
--- a/mysql-test/suite/gcol/r/innodb_virtual_index.result
+++ b/mysql-test/suite/gcol/r/innodb_virtual_index.result
@@ -296,3 +296,17 @@ Table	Op	Msg_type	Msg_text
 test.t1	optimize	note	Table does not support optimize, doing recreate + analyze instead
 test.t1	optimize	status	OK
 DROP TABLE t1;
+#
+# MDEV-20154 Assertion `len <= col->len || ((col->mtype) == 5
+# || (col->mtype) == 14)' failed in row_merge_buf_add
+#
+CREATE TABLE t1 (
+a VARCHAR(2500),
+b VARCHAR(2499) AS (a) VIRTUAL
+) ENGINE=InnoDB;
+INSERT INTO t1 (a) VALUES ('foo');
+ALTER TABLE t1 MODIFY a VARCHAR(2600), ALGORITHM=INPLACE;
+ALTER TABLE t1 ADD KEY (b), ALGORITHM=INPLACE;
+# Cleanup
+DROP TABLE t1;
+# End of 10.2 tests
diff --git a/mysql-test/suite/gcol/t/innodb_virtual_index.test b/mysql-test/suite/gcol/t/innodb_virtual_index.test
index bb47379f3b2..4a41623264e 100644
--- a/mysql-test/suite/gcol/t/innodb_virtual_index.test
+++ b/mysql-test/suite/gcol/t/innodb_virtual_index.test
@@ -321,3 +321,23 @@ CREATE TABLE t1 (id INT PRIMARY KEY, a CHAR(3),
 INSERT INTO t1 (id,a) VALUES (1,'foo');
 OPTIMIZE TABLE t1;
 DROP TABLE t1;
+
+--echo #
+--echo # MDEV-20154 Assertion `len <= col->len || ((col->mtype) == 5
+--echo # || (col->mtype) == 14)' failed in row_merge_buf_add
+--echo #
+
+CREATE TABLE t1 (
+    a VARCHAR(2500),
+    b VARCHAR(2499) AS (a) VIRTUAL
+) ENGINE=InnoDB;
+INSERT INTO t1 (a) VALUES ('foo');
+
+ALTER TABLE t1 MODIFY a VARCHAR(2600), ALGORITHM=INPLACE;
+ALTER TABLE t1 ADD KEY (b), ALGORITHM=INPLACE;
+
+--echo # Cleanup
+DROP TABLE t1;
+
+--echo # End of 10.2 tests
+
diff --git a/sql/table.cc b/sql/table.cc
index 3bfca699b50..ec950c582c3 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -4185,6 +4185,21 @@ enum open_frm_error open_table_from_share(THD *thd, TABLE_SHARE *share,
 
     /* Update to use trigger fields */
     switch_defaults_to_nullable_trigger_fields(outparam);
+
+    for (uint k= 0; k < share->keys; k++)
+    {
+      KEY &key_info= outparam->key_info[k];
+      uint parts = (share->use_ext_keys ? key_info.ext_key_parts :
+                    key_info.user_defined_key_parts);
+      for (uint p= 0; p < parts; p++)
+      {
+        KEY_PART_INFO &kp= key_info.key_part[p];
+        if (kp.field != outparam->field[kp.fieldnr - 1])
+        {
+          kp.field->vcol_info = outparam->field[kp.fieldnr - 1]->vcol_info;
+        }
+      }
+    }
   }
 
 #ifdef WITH_PARTITION_STORAGE_ENGINE
diff --git a/storage/innobase/fts/fts0fts.cc b/storage/innobase/fts/fts0fts.cc
index c48eeeed48a..be05e4fb521 100644
--- a/storage/innobase/fts/fts0fts.cc
+++ b/storage/innobase/fts/fts0fts.cc
@@ -6109,58 +6109,3 @@ func_exit:
 		dict_sys.mutex_unlock();
 	}
 }
-
-/** Check if the all the auxillary tables associated with FTS index are in
-consistent state. For now consistency is check only by ensuring
-index->page_no != FIL_NULL
-@param[out]	base_table	table has host fts index
-@param[in,out]	trx		trx handler */
-void
-fts_check_corrupt(
-	dict_table_t*	base_table,
-	trx_t*		trx)
-{
-	bool		sane = true;
-	fts_table_t	fts_table;
-
-	/* Iterate over the common table and check for their sanity. */
-	FTS_INIT_FTS_TABLE(&fts_table, NULL, FTS_COMMON_TABLE, base_table);
-
-	for (ulint i = 0; fts_common_tables[i] != NULL && sane; ++i) {
-
-		char	table_name[MAX_FULL_NAME_LEN];
-
-		fts_table.suffix = fts_common_tables[i];
-		fts_get_table_name(&fts_table, table_name);
-
-		dict_table_t*	aux_table = dict_table_open_on_name(
-			table_name, true, FALSE, DICT_ERR_IGNORE_NONE);
-
-		if (aux_table == NULL) {
-			dict_set_corrupted(
-				dict_table_get_first_index(base_table),
-				trx, "FTS_SANITY_CHECK");
-			ut_ad(base_table->corrupted == TRUE);
-			sane = false;
-			continue;
-		}
-
-		for (dict_index_t*	aux_table_index =
-			UT_LIST_GET_FIRST(aux_table->indexes);
-		     aux_table_index != NULL;
-		     aux_table_index =
-			UT_LIST_GET_NEXT(indexes, aux_table_index)) {
-
-			/* Check if auxillary table needed for FTS is sane. */
-			if (aux_table_index->page == FIL_NULL) {
-				dict_set_corrupted(
-					dict_table_get_first_index(base_table),
-					trx, "FTS_SANITY_CHECK");
-				ut_ad(base_table->corrupted == TRUE);
-				sane = false;
-			}
-		}
-
-		dict_table_close(aux_table, FALSE, FALSE);
-	}
-}
diff --git a/storage/innobase/handler/handler0alter.cc b/storage/innobase/handler/handler0alter.cc
index af39363047c..9d027140335 100644
--- a/storage/innobase/handler/handler0alter.cc
+++ b/storage/innobase/handler/handler0alter.cc
@@ -7495,6 +7495,10 @@ alter_fill_stored_column(
 	}
 }
 
+static bool alter_templ_needs_rebuild(const TABLE* altered_table,
+                                      const Alter_inplace_info* ha_alter_info,
+                                      const dict_table_t* table);
+
 
 /** Allows InnoDB to update internal structures with concurrent
 writes blocked (provided that check_if_supported_inplace_alter()
@@ -7642,11 +7646,7 @@ ha_innobase::prepare_inplace_alter_table(
 		    ha_alter_info->key_count)) {
 err_exit_no_heap:
 		DBUG_ASSERT(m_prebuilt->trx->dict_operation_lock_mode == 0);
-		if (ha_alter_info->handler_flags & ~INNOBASE_INPLACE_IGNORE) {
-
-			online_retry_drop_indexes(
-				m_prebuilt->table, m_user_thd);
-		}
+		online_retry_drop_indexes(m_prebuilt->table, m_user_thd);
 		DBUG_RETURN(true);
 	}
 
@@ -8095,6 +8095,8 @@ err_exit:
 	const ha_table_option_struct& alt_opt=
 		*ha_alter_info->create_info->option_struct;
 
+        ha_innobase_inplace_ctx *ctx = NULL;
+
 	if (!(ha_alter_info->handler_flags & INNOBASE_ALTER_DATA)
 	    || ((ha_alter_info->handler_flags & ~(INNOBASE_INPLACE_IGNORE
 						  | INNOBASE_ALTER_NOCREATE
@@ -8102,15 +8104,11 @@ err_exit:
 		== ALTER_OPTIONS
 		&& !alter_options_need_rebuild(ha_alter_info, table))) {
 
-		DBUG_ASSERT(!m_prebuilt->trx->dict_operation_lock_mode);
-		if (ha_alter_info->handler_flags & ~INNOBASE_INPLACE_IGNORE) {
-			online_retry_drop_indexes(m_prebuilt->table,
-						  m_user_thd);
-		}
+		DBUG_ASSERT(m_prebuilt->trx->dict_operation_lock_mode == 0);
+		online_retry_drop_indexes(m_prebuilt->table, m_user_thd);
 
 		if (heap) {
-			ha_alter_info->handler_ctx
-				= new ha_innobase_inplace_ctx(
+			ctx = new ha_innobase_inplace_ctx(
 					m_prebuilt,
 					drop_index, n_drop_index,
 					drop_fk, n_drop_fk,
@@ -8122,6 +8120,7 @@ err_exit:
 					 || !thd_is_strict_mode(m_user_thd)),
 					alt_opt.page_compressed,
 					alt_opt.page_compression_level);
+			ha_alter_info->handler_ctx = ctx;
 		}
 
 		if ((ha_alter_info->handler_flags
@@ -8137,6 +8136,25 @@ err_exit:
 			DBUG_RETURN(true);
 		}
 
+		if (!(ha_alter_info->handler_flags & INNOBASE_ALTER_DATA)
+		    && alter_templ_needs_rebuild(altered_table, ha_alter_info,
+						 ctx->new_table)
+		    && ctx->new_table->n_v_cols > 0) {
+			/* Changing maria record structure may end up here only
+			if virtual columns were altered. In this case, however,
+			vc_templ should be rebuilt. Since we don't actually
+			change any stored data, we can just dispose vc_templ;
+			it will be recreated on next ha_innobase::open(). */
+
+			DBUG_ASSERT(ctx->new_table == ctx->old_table);
+
+			dict_free_vc_templ(ctx->new_table->vc_templ);
+			UT_DELETE(ctx->new_table->vc_templ);
+
+			ctx->new_table->vc_templ = NULL;
+		}
+
+
 success:
 		/* Memorize the future transaction ID for committing
 		the data dictionary change, to be reported by
@@ -8261,35 +8279,6 @@ found_col:
 	DBUG_RETURN(true);
 }
 
-/** Check that the column is part of a virtual index(index contains
-virtual column) in the table
-@param[in]	table		Table containing column
-@param[in]	col		column to be checked
-@return true if this column is indexed with other virtual columns */
-static
-bool
-dict_col_in_v_indexes(
-	dict_table_t*	table,
-	dict_col_t*	col)
-{
-	for (dict_index_t* index = dict_table_get_next_index(
-		dict_table_get_first_index(table)); index != NULL;
-		index = dict_table_get_next_index(index)) {
-		if (!dict_index_has_virtual(index)) {
-			continue;
-		}
-		for (ulint k = 0; k < index->n_fields; k++) {
-			dict_field_t*   field
-				= dict_index_get_nth_field(index, k);
-			if (field->col->ind == col->ind) {
-				return(true);
-			}
-		}
-	}
-
-	return(false);
-}
-
 /* Check whether a columnn length change alter operation requires
 to rebuild the template.
 @param[in]	altered_table	TABLE object for new version of table.
@@ -8301,9 +8290,9 @@ to rebuild the template.
 static
 bool
 alter_templ_needs_rebuild(
-	TABLE*                  altered_table,
-	Alter_inplace_info*     ha_alter_info,
-	dict_table_t*		table)
+	const TABLE*            altered_table,
+	const Alter_inplace_info*     ha_alter_info,
+	const dict_table_t*		table)
 {
         ulint	i = 0;
 
@@ -8313,8 +8302,7 @@ alter_templ_needs_rebuild(
 			for (ulint j=0; j < table->n_cols; j++) {
 				dict_col_t* cols
                                    = dict_table_get_nth_col(table, j);
-				if (cf.length > cols->len
-				    && dict_col_in_v_indexes(table, cols)) {
+				if (cf.length > cols->len) {
 					return(true);
 				}
 			}
diff --git a/storage/innobase/include/fts0fts.h b/storage/innobase/include/fts0fts.h
index bb61eae43f2..95b5131a526 100644
--- a/storage/innobase/include/fts0fts.h
+++ b/storage/innobase/include/fts0fts.h
@@ -931,16 +931,6 @@ fts_check_cached_index(
 /*===================*/
 	dict_table_t*	table);  /*!< in: Table where indexes are dropped */
 
-/** Check if the all the auxillary tables associated with FTS index are in
-consistent state. For now consistency is check only by ensuring
-index->page_no != FIL_NULL
-@param[out]	base_table	table has host fts index
-@param[in,out]	trx		trx handler */
-void
-fts_check_corrupt(
-	dict_table_t*	base_table,
-	trx_t*		trx);
-
 /** Fetch the document from tuple, tokenize the text data and
 insert the text data into fts auxiliary table and
 its cache. Moreover this tuple fields doesn't contain any information