Configuration Information [Automatically generated, do not change]: Machine: x86_64 OS: linux-gnu Compiler: gcc Compilation CFLAGS: -march=x86-64 -mtune=generic -O2 -pipe -fno-plt -DDEFAULT_PATH_VALUE='/usr/local/sbin:/usr/local/bin:/usr/bin' -DSTANDARD_UTILS_PATH='/usr/bin' -DSYS_BASHRC='/etc/bash/bashrc' -DSYS_BASH_LOGOUT='/etc/bash/bash_logout' -DNON_INTERACTIVE_LOGIN_SHELLS -Wno-parentheses -Wno-format-security uname output: Linux arctic 5.5.6-artix1-1 #1 SMP PREEMPT Tue, 25 Feb 2020 14:57:48 +0000 x86_64 GNU/Linux Machine Type: x86_64-pc-linux-gnu
Bash Version: 5.0 Patch Level: 16 Release Status: release Description: Out of nowhere, bash inserts an ascii DEL in the first expansion. That is very unexpected and shouldn't be there. Repeat-By: $ unset foo bar $ echo "${foo:=}/baz:${foo}/bat"|xxd 00000000: 7f2f 6261 7a3a 2f62 6174 0a ./baz:/bat. $ echo "${foo:=$bar}/baz:${foo}/bat"|xxd 00000000: 7f2f 6261 7a3a 2f62 6174 0a ./baz:/bat.