UBSAN: Many overflow issues in strings/decimal.c - runtime error: signed integer overflow: x * y cannot be represented in type 'long long int' (on optimized builds)

SELECT RIGHT('a', -10000000000000000000);

SELECT LPAD (0,-18446744073709551615,0);

SELECT RPAD (0,-18446744073709551615,0);

SELECT LOCATE (0,0,-18446744073709551615);

SELECT INSERT (0,18446744073709551616,1,0);

SELECT HEX(COLUMN_CREATE (1,99999999999999999999999999999 AS INT));

SELECT COLUMN_GET (COLUMN_CREATE (1,99999999999999999999999999999 AS DECIMAL),1 AS INT);

SELECT 0 + (10101010101010101010101010101010101010101010101010101010101010101<<4);

Compiled with GCC >=7.5.0 (I use GCC 9.3.0) and:

    -DWITH_ASAN=ON -DWITH_ASAN_SCOPE=ON -DWITH_UBSAN=ON -DWITH_RAPID=OFF -DWSREP_LIB_WITH_ASAN=ON

Set before execution:

    export UBSAN_OPTIONS=print_stacktrace=1