posix mode changes for interp 1150; fix for varassign redirection; fix for nameref in ${param=value} expansion

doc/bashref.texi

@@ -8561,6 +8561,13 @@ undergoes expansion.
 That means, for example, that a backslash preceding a double quote
 character will escape it and the backslash will be removed.
 
+@item
+Command substitutions don't set the @samp{?} special parameter. The exit
+status of a simple command without a command word is still the exit status
+of the last command substitution that occurred while evaluating the variable
+assignments and redirections in that command, but that does not happen until
+after all of the assignments and redirections.
+
 @end enumerate
 
 There is other @sc{posix} behavior that Bash does not implement by

doc/version.texi

@@ -2,10 +2,10 @@
 Copyright (C) 1988-2023 Free Software Foundation, Inc.
 @end ignore
 
-@set LASTCHANGE Tue Mar 21 11:05:49 EDT 2023
+@set LASTCHANGE Thu Apr  6 11:58:41 EDT 2023
 
 @set EDITION 5.2
 @set VERSION 5.2
 
-@set UPDATED 21 March 2023
-@set UPDATED-MONTH March 2023
+@set UPDATED 6 April 2023
+@set UPDATED-MONTH April 2023