Bug #27141613 ASSERTION: TRX0REC.CC:319:COL->IS_VIRTUAL() / CRASH IN TRX_UNDO_READ_V_COLS

PROBLEM
=======
When add of virtual index fails with DB_TOO_BIG_RECORD , the virtual
index being freed isn't removed from the list of indexes a virtual
column(which is part of the index). This while the undo log is read
could fetch a wrong value during rollback and cause the assertion
reported in the bug particularly.

FIX
===
Added a function that is called when the virtual index being freed would
allow the index be removed from the index list of virtual column which
was a field of that index.

Reviwed By: Jimmy Yang<Jimmy.Yang@oracle.com>
RB: 18528

storage/innobase/dict/dict0dict.cc

@@ -2428,6 +2428,41 @@ dict_index_add_to_cache(
 		table, index, NULL, page_no, strict));
 }
 
+/** Clears the virtual column's index list before index is
+being freed.
+@param[in]  index   Index being freed */
+void
+dict_index_remove_from_v_col_list(dict_index_t* index) {
+
+        if (dict_index_has_virtual(index)) {
+                const dict_col_t*       col;
+                const dict_v_col_t*     vcol;
+
+                for (ulint i = 0; i < dict_index_get_n_fields(index); i++) {
+                        col =  dict_index_get_nth_col(index, i);
+                        if (dict_col_is_virtual(col)) {
+                                vcol = reinterpret_cast<const dict_v_col_t*>(
+                                        col);
+				/* This could be NULL, when we do add
+                                virtual column, add index together. We do not
+                                need to track this virtual column's index */
+				if (vcol->v_indexes == NULL) {
+                                        continue;
+                                }
+				dict_v_idx_list::iterator       it;
+				for (it = vcol->v_indexes->begin();
+                                     it != vcol->v_indexes->end(); ++it) {
+                                        dict_v_idx_t    v_index = *it;
+                                        if (v_index.index == index) {
+                                                vcol->v_indexes->erase(it);
+                                                break;
+                                        }
+				}
+			}
+		}
+	}
+}
+
 /** Adds an index to the dictionary cache, with possible indexing newly
 added column.
 @param[in,out]	table	table on which the index is

storage/innobase/dict/dict0mem.cc

 /*****************************************************************************
 
-Copyright (c) 1996, 2016, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 1996, 2018, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2012, Facebook Inc.
 Copyright (c) 2013, 2018, MariaDB Corporation.
 
@@ -1034,6 +1034,7 @@ dict_mem_index_free(
 		UT_DELETE(index->rtr_track->rtr_active);
 	}
 
+	dict_index_remove_from_v_col_list(index);
 	mem_heap_free(index->heap);
 }
 

storage/innobase/include/dict0dict.h

 /*****************************************************************************
 
-Copyright (c) 1996, 2016, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 1996, 2018, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2012, Facebook Inc.
 Copyright (c) 2013, 2018, MariaDB Corporation.
 
@@ -1121,6 +1121,12 @@ dict_index_add_to_cache(
 	ibool		strict)
 	MY_ATTRIBUTE((warn_unused_result));
 
+/** Clears the virtual column's index list before index is being freed.
+@param[in]  index   Index being freed */
+void
+dict_index_remove_from_v_col_list(
+	dict_index_t* index);
+
 /** Adds an index to the dictionary cache, with possible indexing newly
 added column.
 @param[in]	table	table on which the index is