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Message-ID: <95477c93db187bab6da8a8ba7c57836868446179.camel@perches.com>
Subject: [PATCH] checkpatch: Add a --strict test for structs with bool
 member definitions
From:   Joe Perches <joe@perches.com>
To:     Peter Zijlstra <peterz@infradead.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andy Whitcroft <apw@canonical.com>
Cc:     yuankuiz@codeaurora.org, Linux PM <linux-pm@vger.kernel.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        paulmck@linux.vnet.ibm.com, Ingo Molnar <mingo@kernel.org>,
        Len Brown <len.brown@intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Date:   Tue, 10 Apr 2018 11:19:54 -0700
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A struct with a bool member can have different sizes on various
architectures because neither bool size nor alignment is standardized.

So emit a message on the use of bool in structs only in .h files and
not .c files.

There is the real possibility that this test could have a false positive
when a bool is declared as an automatic, so limit the test to .h files
where the only false positive is for declarations in static inline functions.

Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
---
 scripts/checkpatch.pl | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index e16d6713f236..24618dffc5cb 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -6257,6 +6257,13 @@ sub process {
 			     "Avoid using bool as bitfield.  Prefer bool bitfields as unsigned int or u<8|16|32>\n" . $herecurr);
 		}
 
+# check for bool use in .h files
+		if ($realfile =~ /\.h$/ &&
+		    $sline =~ /^.\s+bool\s*$Ident\s*(?::\s*d+\s*)?;/) {
+			CHK("BOOL_MEMBER",
+			    "Avoid using bool structure members because of possible alignment issues - see: https://lkml.org/lkml/2017/11/21/384\n" . $herecurr);
+		}
+
 # check for semaphores initialized locked
 		if ($line =~ /^.\s*sema_init.+,\W?0\W?\)/) {
 			WARN("CONSIDER_COMPLETION",
-- 
2.15.0