bug#42296: 27.0.91; Correct manual entry for 'concat' w.r.t. allocation [PATCH]

["Mattias Engdegård" <mattiase@acm.org>]

[-- Attachment #1: Type: text/plain, Size: 143 bytes --]

'concat' hasn't guaranteed the allocation of a new string since 1997 at least (79d137ffe7d). Remove claims to the contrary from the manual.


[-- Attachment #2: 0001-Correct-concat-manual-entry.patch --]
[-- Type: application/octet-stream, Size: 1658 bytes --]

From 3c6d4f9cefc7571df26e390b94f1c39da08a78e1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mattias=20Engdeg=C3=A5rd?= <mattiase@acm.org>
Date: Thu, 9 Jul 2020 17:32:13 +0200
Subject: [PATCH] Correct 'concat' manual entry

* doc/lispref/strings.texi (Creating Strings): 'concat' does not
necessarily return a newly allocated string.  This has been the case
at least since 1997 (Emacs 20.3).
---
 doc/lispref/strings.texi | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/doc/lispref/strings.texi b/doc/lispref/strings.texi
index 2ef88b9025..0aab326dc7 100644
--- a/doc/lispref/strings.texi
+++ b/doc/lispref/strings.texi
@@ -248,7 +248,7 @@ Creating Strings
 @defun concat &rest sequences
 @cindex copying strings
 @cindex concatenating strings
-This function returns a new string consisting of the characters in the
+This function returns a string consisting of the characters in the
 arguments passed to it (along with their text properties, if any).  The
 arguments may be strings, lists of numbers, or vectors of numbers; they
 are not themselves changed.  If @code{concat} receives no arguments, it
@@ -269,10 +269,6 @@ Creating Strings
 @end example
 
 @noindent
-This function always constructs a new string that is not @code{eq} to
-any existing string, except when the result is the empty string (to
-save space, Emacs makes only one empty multibyte string).
-
 For information about other concatenation functions, see the
 description of @code{mapconcat} in @ref{Mapping Functions},
 @code{vconcat} in @ref{Vector Functions}, and @code{append} in @ref{Building
-- 
2.21.1 (Apple Git-122.3)