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From:   Paul Menzel <pmenzel@molgen.mpg.de>
To:     Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>
Cc:     Christophe Leroy <christophe.leroy@csgroup.eu>,
        Zhen Lei <thunder.leizhen@huawei.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        linuxppc-dev@lists.ozlabs.org, Paul Menzel <pmenzel@molgen.mpg.de>,
        linux-kernel@vger.kernel.org, llvm@lists.linux.dev
Subject: [PATCH v3] lib/zlib_inflate/inffast: Check config in C to avoid unused function warning
Date:   Mon, 20 Sep 2021 10:43:33 +0200
Message-Id: <20210920084332.5752-1-pmenzel@molgen.mpg.de>
MIME-Version: 1.0
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Building Linux for ppc64le with Ubuntu clang version 12.0.0-3ubuntu1~21.04.1
shows the warning below.

    arch/powerpc/boot/inffast.c:20:1: warning: unused function 'get_unaligned16' [-Wunused-function]
    get_unaligned16(const unsigned short *p)
    ^
    1 warning generated.

Fix it, by moving the check from the preprocessor to C, so the compiler
sees the use.

Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
---
v2: Use IS_ENABLED
v3: Use if statement over ternary operator as requested by Christophe

 lib/zlib_inflate/inffast.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/lib/zlib_inflate/inffast.c b/lib/zlib_inflate/inffast.c
index f19c4fbe1be7..2843f9bb42ac 100644
--- a/lib/zlib_inflate/inffast.c
+++ b/lib/zlib_inflate/inffast.c
@@ -253,13 +253,12 @@ void inflate_fast(z_streamp strm, unsigned start)
 
 			sfrom = (unsigned short *)(from);
 			loops = len >> 1;
-			do
-#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
-			    *sout++ = *sfrom++;
-#else
-			    *sout++ = get_unaligned16(sfrom++);
-#endif
-			while (--loops);
+			do {
+			    if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS))
+				*sout++ = *sfrom++;
+			    else
+				*sout++ = get_unaligned16(sfrom++);
+			} while (--loops);
 			out = (unsigned char *)sout;
 			from = (unsigned char *)sfrom;
 		    } else { /* dist == 1 or dist == 2 */
-- 
2.33.0