fix for namerefs referencing an unset array index with nounset enabled; addition to buildconf.h.in for C23 compilers

tests/braces.right

@@ -78,6 +78,9 @@ a ../a.cfg
 a.. /a.cfg
 a..b /a.cfg
 a b../a.cfg
+1..4 5..8
+1..4 8
+1 5..8
 {abcde.f}
 X{..a}Z
 0{1..}2

tests/braces.tests

@@ -147,6 +147,10 @@ echo {a..,/a.cfg}
 echo {a..b,/a.cfg}
 echo {a,b../a.cfg}
 
+echo {1..4,5..8}
+echo {1..4,8}
+echo {1,5..8}
+
 # these are all invalid brace expansions
 
 echo {abcde.f}

tests/nameref.right

@@ -535,16 +535,16 @@ declare -ai a=([0]="5")
 declare -ai a=([0]="6")
 declare -ai a=([0]="42")
 declare -ai a=([0]="1")
-./nameref23.sub: line 16: declare: b: not found
+./nameref23.sub: line 29: declare: b: not found
 declare -ai a=([0]="1")
 declare -- b="1"
 declare -ai a=([0]="1")
 declare -- b="11"
 declare -ai a=([0]="1")
 declare -- b="110"
-./nameref23.sub: line 26: declare: `1': invalid variable name for name reference
+./nameref23.sub: line 39: declare: `1': invalid variable name for name reference
 declare -ai a=([0]="1")
-./nameref23.sub: line 28: declare: b: not found
+./nameref23.sub: line 41: declare: b: not found
 declare -ai a=([0]="4")
 declare -in b="a[0]"
 declare -ai a=([0]="6")
@@ -574,3 +574,15 @@ declare -ai a=([0]="0" [1]="16")
 3
 3
 5
+/usr/local/build/bash/bash-current/bash: line 1: a[k]: unbound variable
+ok 1
+/usr/local/build/bash/bash-current/bash: line 1: r0: unbound variable
+ok 2
+/usr/local/build/bash/bash-current/bash: line 1: r: unbound variable
+ok 3
+/usr/local/build/bash/bash-current/bash: line 1: k: unbound variable
+ok 4
+ok 5
+ok 6
+ok 7
+ok 8

tests/nameref23.sub

@@ -1,3 +1,16 @@
+#   This program is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, either version 3 of the License, or
+#   (at your option) any later version.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
 declare -ai a
 a[0]=4
 declare -n b='a[0]'

tests/nameref25.sub

@@ -0,0 +1,12 @@
+# issues with nounset and references to nameref variables whose value
+# contains an unset variable
+
+$THIS_SH -uc 'a=() k=; "${a[k]}"' ||  echo ok 1
+$THIS_SH -uc 'declare -n r0=b ; : "$r0"' || echo ok 2
+$THIS_SH -uc 'a=() k=; declare -n r='a[k]' ; : "$r"' || echo ok 3
+$THIS_SH -uc 'declare -n r='a[k]' ; : "$r"' || echo ok 4
+
+$THIS_SH -uc 'a=() k=; declare -n r='a[@]' ; : "$r"' && echo ok 5
+$THIS_SH -uc 'declare -n r='a[@]' ; : "$r"' && echo ok 6
+$THIS_SH -uc 'a=() k=; declare -n r='a[*]' ; : "$r"' && echo ok 7
+$THIS_SH -uc 'declare -n r='a[*]' ; : "$r"' && echo ok 8