[#MDEV-18749] rec_get_converted_size_comp_prefix_low: Conditional jump or move depends on uninitialised value upon adding FULLTEXT index

--source include/have_innodb.inc

CREATE TABLE t1 (c CHAR(255)) ENGINE=InnoDB;

INSERT INTO t1 VALUES ('alternative'),('minds');

ALTER TABLE t1 ADD FULLTEXT INDEX (c);

# Cleanup

DROP TABLE t1;

10.4 bb970dda Valgrind
==5989== Thread 29:
==5989== Conditional jump or move depends on uninitialised value(s)
==5989== at 0x106EF79: unsigned long rec_get_converted_size_comp_prefix_low<false>(dict_index_t const, dfield_t const, unsigned long, unsigned long*, rec_comp_status_t, bool) (rem0rec.cc:1191)
==5989== by 0x106A179: rec_get_converted_size_temp(dict_index_t const, dfield_t const, unsigned long, unsigned long*, rec_comp_status_t) (rem0rec.cc:1796)
==5989== by 0x109F2FC: row_merge_buf_encode(unsigned char*, dict_index_t const, mtuple_t const*, unsigned long) (row0merge.cc:317)
==5989== by 0x10A1397: row_merge_buf_write(row_merge_buf_t const, merge_file_t const, unsigned char*) (row0merge.cc:1021)
==5989== by 0x1076905: fts_parallel_tokenization(void*) (row0ftsort.cc:963)
==5989== by 0x4E3F493: start_thread (pthread_create.c:333)
==5989== by 0x6A9A93E: clone (clone.S:97)
==5989== Conditional jump or move depends on uninitialised value(s)
==5989== at 0x106F3AF: unsigned long rec_get_converted_size_comp_prefix_low<false>(dict_index_t const, dfield_t const, unsigned long, unsigned long*, rec_comp_status_t, bool) (rem0rec.cc:1235)
==5989== by 0x106A179: rec_get_converted_size_temp(dict_index_t const, dfield_t const, unsigned long, unsigned long*, rec_comp_status_t) (rem0rec.cc:1796)
==5989== by 0x109F2FC: row_merge_buf_encode(unsigned char*, dict_index_t const, mtuple_t const*, unsigned long) (row0merge.cc:317)
==5989== by 0x10A1397: row_merge_buf_write(row_merge_buf_t const, merge_file_t const, unsigned char*) (row0merge.cc:1021)
==5989== by 0x1076905: fts_parallel_tokenization(void*) (row0ftsort.cc:963)
==5989== by 0x4E3F493: start_thread (pthread_create.c:333)
==5989== by 0x6A9A93E: clone (clone.S:97)

Not reproducible on 10.3.
Nothing obvious happens on non-valgrind builds (debug, ASAN, relwithdebinfo).

[MDEV-18749] rec_get_converted_size_comp_prefix_low: Conditional jump or move depends on uninitialised value upon adding FULLTEXT index Created: 2019-02-26 Updated: 2019-03-12 Resolved: 2019-03-06
Status:	Closed
Project:	MariaDB Server
Component/s:	Storage Engine - InnoDB, Storage Engine - XtraDB
Affects Version/s:	10.4
Fix Version/s:	10.2.23, 10.1.39, 10.3.14, 10.4.4

[MDEV-18749] rec_get_converted_size_comp_prefix_low: Conditional jump or move depends on uninitialised value upon adding FULLTEXT index Created: 2019-02-26 Updated: 2019-03-12 Resolved: 2019-03-06