Subject: 27.1; [C] wrong indent for knr-style arguments declaration

From: Bruno <[email-masked]>
Date: Thu, 10 Dec 2020 16:02:02 +0100

Within "emacs -Q" session, open the following C source file:

------------------------------ foo.c
int f(i, j, k)
int i;
int j;
int k;
{
return 1;
}

int g(i, j, k)
int i;
int j, k;
{
return 1;
}
------------------------------

Then, do "C-c ." (c-set-style) to "k&r", and "c-c c-o" (c-set-offset),
and set "knr-argdecl-intro" to "+".

We have now the following values in c-offsets-alist :
knr-argdecl-intro : +  (First line of a K&R C argument declaration)
knr-argdecl : 0        (Subsequent lines in a K&R C argument declaration)

re-indent foo.c. At this stage we expect the following indentation for
arguments declarations.

------------------------------ expected indentation
int f(i, j, k)
    int i;
    int j;
    int k;
{
    return 1;
}

int g(i, j, k)
    int i;
    int j, k;
{
    return 1;
}
------------------------------

But we get the following result (please note line 11).

------------------------------ emacs indentation
int f(i, j, k)
    int i;
    int j;
    int k;
{
    return 1;
}

int g(i, j, k)
    int i;
int j, k;
{
    return 1;
}
------------------------------

It should be noted that if we separate each argument on separate lines
(function f), indentation is correct.
It is incorrect if multiple variables are in same declaration (function
g).

Also, multiple variables on first arguments declaration line seems to
have correct indentation.

Regards,

Bruno.

In GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 2.24.32)
 of 2020-10-29 built on lorien
Windowing system distributor 'The X.Org Foundation', version 11.0.12008000
System Description: Ubuntu 20.04.1 LTS

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