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Message-ID: <f19f55f13682a6c019be2a67e4acb07e94e103f3.camel@perches.com>
Subject: Re: [PATCH v3] Documentation/process/coding-style.rst: space around
 const
From:   Joe Perches <joe@perches.com>
To:     Max Kellermann <max.kellermann@ionos.com>, linux@roeck-us.net,
        gregkh@linuxfoundation.org, Jonathan Corbet <corbet@lwn.net>
Cc:     workflows@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org
Date:   Tue, 10 Oct 2023 17:45:55 -0700
In-Reply-To: <20231010125832.1002941-1-max.kellermann@ionos.com>
References: <20231010125832.1002941-1-max.kellermann@ionos.com>
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On Tue, 2023-10-10 at 14:58 +0200, Max Kellermann wrote:
> There are currently no rules on the placement of "const", but a recent
> code submission revealed that there is clearly a preference for spaces
> around it.
> 
> checkpatch.pl has no check at all for this; though it does sometimes
> complain, but only because it erroneously thinks that the "*" (on
> local variables) is an unary dereference operator, not a pointer type.
> 

Maybe something like this for checkpatch:
---
 scripts/checkpatch.pl | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 25fdb7fda1128..48d70d0ad9a2b 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4726,6 +4726,16 @@ sub process {
 			}
 		}
 
+# check for const* and *const uses that should have space around const
+		if ($line =~ /(?:const\*|\*const)/) {
+			if (WARN("CONST_POINTER",
+				 "const pointers should have spaces around const\n" . $herecurr) &&
+			    $fix) {
+				$fixed[$fixlinenr] =~ s/\*const\b/* const/g;
+				$fixed[$fixlinenr] =~ s/\bconst\*/const */g;
+			}
+		}
+
 # check for non-global char *foo[] = {"bar", ...} declarations.
 		if ($line =~ /^.\s+(?:static\s+|const\s+)?char\s+\*\s*\w+\s*\[\s*\]\s*=\s*\{/) {
 			WARN("STATIC_CONST_CHAR_ARRAY",