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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
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Subject: [PATCH v5 13/15] Compiler Attributes: enable -Wstringop-truncation on W=1 (gcc >= 8)
Date:   Thu, 20 Sep 2018 19:22:59 +0200
Message-Id: <20180920172301.21868-14-miguel.ojeda.sandonis@gmail.com>
In-Reply-To: <20180920172301.21868-1-miguel.ojeda.sandonis@gmail.com>
References: <20180920172301.21868-1-miguel.ojeda.sandonis@gmail.com>
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Commit 217c3e019675 ("disable stringop truncation warnings for now")
disabled -Wstringop-truncation since it was too noisy.

Having __nonstring available allows us to let GCC know that a string
is not meant to be NUL-terminated, which helps suppressing some
-Wstringop-truncation warnings.

Note that using __nonstring actually triggers other warnings
(-Wstringop-overflow, which is on by default) which may be real
problems. Therefore, cleaning up -Wstringop-truncation warnings
also buys us the ability to uncover further potential problems.

To encourage the use of __nonstring, we put the warning back at W=1.
In the future, if we end up with a fairly warning-free tree,
we might want to enable it by default.

Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
---
 scripts/Makefile.extrawarn | 1 +
 1 file changed, 1 insertion(+)

diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 8d5357053f86..b8f36f5f43f2 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -29,6 +29,7 @@ warning-1 += $(call cc-option, -Wmissing-include-dirs)
 warning-1 += $(call cc-option, -Wunused-but-set-variable)
 warning-1 += $(call cc-option, -Wunused-const-variable)
 warning-1 += $(call cc-option, -Wpacked-not-aligned)
+warning-1 += $(call cc-option, -Wstringop-truncation)
 warning-1 += $(call cc-disable-warning, missing-field-initializers)
 warning-1 += $(call cc-disable-warning, sign-compare)
 
-- 
2.17.1