2021-02-20 14:47:46 +00:00
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From 2e2417894ac5d35bc3d93b86c18f4df299f4d933 Mon Sep 17 00:00:00 2001
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2022-05-07 10:56:11 +00:00
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From: graysky <therealgraysky@proton.me>
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2021-02-20 14:47:46 +00:00
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Date: Sat, 12 Dec 2020 09:10:28 -0500
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Subject: [PATCH] use -mcpu= avoiding -march and -mtune for armv7h
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From what I understand, when building on ARM, it's best to avoid the -march=
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flag and rather use -mcpu= flag due to differences in meaning on ARM vs x86[1].
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Additionally, this patch avoids thousands of warns like the following when
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building for armv7h:
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cc1: warning: switch '-mcpu=cortex-a72' conflicts with '-march=armv8-a'
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This is due to the way ffmpeg's configure script defines -march=armv8-a when it
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encounters any cortex-a* passed to it.
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for reference and to experiment:
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untar ffmpeg, run ./configure, then inspect the output of ffbuild/config.mak and adjust:
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kodi-build/build/ffmpeg/src/ffmpeg-build/ffmpeg-prefix/src/ffmpeg-build/ffbuild/config.mak
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1. https://community.arm.com/developer/tools-software/tools/b/tools-software-ides-blog/posts/compiler-flags-across-architectures-march-mtune-and-mcpu
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---
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configure | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/configure b/configure
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index 8569a60..0d3aafb 100755
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--- a/configure
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+++ b/configure
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@@ -4948,7 +4948,7 @@ elif enabled arm; then
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case $cpu in
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armv*)
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- cpuflags="-march=$cpu"
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+ cpuflags="-mcpu=cortex-a53"
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subarch=$(echo $cpu | sed 's/[^a-z0-9]//g')
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;;
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*)
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--
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2.29.2
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