From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nathan Chancellor Subject: [PATCH 2/6] kernel/extable: Wrap section comparison in sort_main_extable with COMPARE_SECTIONS Date: Tue, 18 Feb 2020 21:54:19 -0700 Message-ID: <20200219045423.54190-3-natechancellor@gmail.com> References: <20200219045423.54190-1-natechancellor@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200219045423.54190-1-natechancellor@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Masahiro Yamada , Michal Marek , Arnd Bergmann , Steven Rostedt , Ingo Molnar , Jason Baron , Catalin Marinas , Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, clang-built-linux@googlegroups.com, Nathan Chancellor List-Id: linux-arch.vger.kernel.org Clang warns: ../kernel/extable.c:37:52: warning: array comparison always evaluates to a constant [-Wtautological-compare] if (main_extable_sort_needed && __stop___ex_table > __start___ex_table) { ^ 1 warning generated. These are not true arrays, they are linker defined symbols, which are just addresses so there is not a real issue here. Use the COMPARE_SECTIONS macro to silence this warning by casting the linker defined symbols to unsigned long, which keeps the logic the same. Link: https://github.com/ClangBuiltLinux/linux/issues/765 Signed-off-by: Nathan Chancellor --- kernel/extable.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/extable.c b/kernel/extable.c index a0024f27d3a1..17bf4ccb9de9 100644 --- a/kernel/extable.c +++ b/kernel/extable.c @@ -34,7 +34,8 @@ u32 __initdata __visible main_extable_sort_needed = 1; /* Sort the kernel's built-in exception table */ void __init sort_main_extable(void) { - if (main_extable_sort_needed && __stop___ex_table > __start___ex_table) { + if (main_extable_sort_needed && + COMPARE_SECTIONS(__stop___ex_table, >, __start___ex_table)) { pr_notice("Sorting __ex_table...\n"); sort_extable(__start___ex_table, __stop___ex_table); } -- 2.25.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Nathan Chancellor Subject: [PATCH 2/6] kernel/extable: Wrap section comparison in sort_main_extable with COMPARE_SECTIONS Date: Tue, 18 Feb 2020 21:54:19 -0700 Message-ID: <20200219045423.54190-3-natechancellor@gmail.com> In-Reply-To: <20200219045423.54190-1-natechancellor@gmail.com> References: <20200219045423.54190-1-natechancellor@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org To: Masahiro Yamada , Michal Marek , Arnd Bergmann , Steven Rostedt , Ingo Molnar , Jason Baron , Catalin Marinas , Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, clang-built-linux@googlegroups.com, Nathan Chancellor List-ID: Message-ID: <20200219045419.PP4452DeROJfsO58UIKzOBNjVZ3KyfdLhD9QWQ6hDqg@z> Clang warns: ../kernel/extable.c:37:52: warning: array comparison always evaluates to a constant [-Wtautological-compare] if (main_extable_sort_needed && __stop___ex_table > __start___ex_= table) { ^ 1 warning generated. These are not true arrays, they are linker defined symbols, which are just addresses so there is not a real issue here. Use the COMPARE_SECTIONS macro to silence this warning by casting the linker defined symbols to unsigned long, which keeps the logic the same. Link: https://github.com/ClangBuiltLinux/linux/issues/765 Signed-off-by: Nathan Chancellor --- kernel/extable.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/extable.c b/kernel/extable.c index a0024f27d3a1..17bf4ccb9de9 100644 --- a/kernel/extable.c +++ b/kernel/extable.c @@ -34,7 +34,8 @@ u32 __initdata __visible main_extable_sort_needed =3D 1= ; /* Sort the kernel's built-in exception table */ void __init sort_main_extable(void) { - if (main_extable_sort_needed && __stop___ex_table > __start___ex_table)= { + if (main_extable_sort_needed && + COMPARE_SECTIONS(__stop___ex_table, >, __start___ex_table)) { pr_notice("Sorting __ex_table...\n"); sort_extable(__start___ex_table, __stop___ex_table); } --=20 2.25.1