[PATCH 2/2] kunit: Assign strings to 'const char*' in STREQ assertions

From: David Gow <davidgow@google.com>
To: Brendan Higgins <brendanhiggins@google.com>,
	Daniel Latypov <dlatypov@google.com>,
	Shuah Khan <skhan@linuxfoundation.org>
Cc: David Gow <davidgow@google.com>,
	kunit-dev@googlegroups.com, linux-kselftest@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH 2/2] kunit: Assign strings to 'const char*' in STREQ assertions
Date: Thu,  6 May 2021 22:09:08 -0700	[thread overview]
Message-ID: <20210507050908.1008686-2-davidgow@google.com> (raw)
In-Reply-To: <20210507050908.1008686-1-davidgow@google.com>

Currently, the KUNIT_EXPECT_STREQ() and related macros assign both
string arguments to variables of their own type (via typeof()). This
seems to be to prevent the macro argument from being evaluated multiple
times.

However, yhis doesn't work if one of these is a fixed-length character
array, rather than a character pointer, as (for example) char[16] will
always allocate a new string.

By always using 'const char*' (the type strcmp expects), we're always
just taking a pointer to the string, which works even with character
arrays.

Signed-off-by: David Gow <davidgow@google.com>
---
 include/kunit/test.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/kunit/test.h b/include/kunit/test.h
index 4c56ffcb7403..b68c61348121 100644
--- a/include/kunit/test.h
+++ b/include/kunit/test.h
@@ -1128,8 +1128,8 @@ do {									       \
 				   fmt,					       \
 				   ...)					       \
 do {									       \
-	typeof(left) __left = (left);					       \
-	typeof(right) __right = (right);				       \
+	const char *__left = (left);					       \
+	const char *__right = (right);				       \
 									       \
 	KUNIT_ASSERTION(test,						       \
 			strcmp(__left, __right) op 0,			       \
-- 
2.31.1.607.g51e8a6a459-goog

