From: Matthias Kaehlcke <mka@chromium.org>
To: Masahiro Yamada <yamada.masahiro@socionext.com>,
Michal Marek <michal.lkml@markovi.net>
Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org,
Behan Webster <behanw@converseincode.com>,
Peter Zijlstra <peterz@infradead.org>,
"H . Peter Anvin" <hpa@zytor.com>,
Nick Desaulniers <ndesaulniers@google.com>,
Manoj Gupta <manojgupta@chromium.org>,
Tiancong Wang <tcwang@chromium.org>,
Stephen Hines <srhines@google.com>,
clang-built-linux@googlegroups.com,
Matthias Kaehlcke <mka@chromium.org>
Subject: [PATCH] Revert "kbuild: use -Oz instead of -Os when using clang"
Date: Mon, 18 Mar 2019 17:10:05 -0400 [thread overview]
Message-ID: <CAG5bF+RvumzKK0E-GAT223jnBvkRe1RN_0J9cGpfPOqCBvfWyw@mail.gmail.com> (raw)
The clang option -Oz enables *aggressive* optimization for size,
which doesn't necessarily result in smaller images, but can have
negative impact on performance. Switch back to the less aggressive
-Os.
This reverts commit 6748cb3c299de1ffbe56733647b01dbcc398c419.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
---
Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/Makefile b/Makefile
index 9ef547fc7ffe..191f3ce3cb5e 100644
--- a/Makefile
+++ b/Makefile
@@ -667,7 +667,7 @@ KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
-KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
+KBUILD_CFLAGS += -Os
else
KBUILD_CFLAGS += -O2
endif
--
2.21.0.225.g810b269d1ac-goog
next reply other threads:[~2019-03-18 21:10 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-18 21:10 Matthias Kaehlcke [this message]
2019-03-18 21:47 ` [PATCH] Revert "kbuild: use -Oz instead of -Os when using clang" Nick Desaulniers
2019-03-18 21:56 ` Matthias Kaehlcke
2019-03-18 22:07 ` hpa
2019-03-18 22:23 ` Nick Desaulniers
2019-03-20 13:28 ` Masahiro Yamada
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAG5bF+RvumzKK0E-GAT223jnBvkRe1RN_0J9cGpfPOqCBvfWyw@mail.gmail.com \
--to=mka@chromium.org \
--cc=behanw@converseincode.com \
--cc=clang-built-linux@googlegroups.com \
--cc=hpa@zytor.com \
--cc=linux-kbuild@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=manojgupta@chromium.org \
--cc=michal.lkml@markovi.net \
--cc=ndesaulniers@google.com \
--cc=peterz@infradead.org \
--cc=srhines@google.com \
--cc=tcwang@chromium.org \
--cc=yamada.masahiro@socionext.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).