Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64'
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-unknown-linux-gnu'
-DCONF_VENDOR='unknown' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash'
-DSHELL -DHAVE_CONFIG_H -I. -I. -I./include -I./lib -D_FORTIFY_SOURCE=2
-march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong
-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' -Wno-parentheses -Wno-format-security
Machine Type: x86_64-unknown-linux-gnu
Bash Version: 4.4
Patch Level: 5
Release Status: release
Description:
Performing variable indirection using an empty value causes an error. It didn't
in Bash 4.3.
Repeat-By:
$ reference=1
$ echo ${!indirect} #variable indirection using an unset variable
$ indirect=reference
$ echo ${!indirect} #variable indirection to a variable name
1
$ indirect=
$ echo ${!indirect} #variable indirection using an empty variable
-bash: : bad substitution
The expected behavior is that the result of an indirection be the same whether
the indirect variable is empty or unset.
