From 6a03567490d90a28363e2093a416e350b1a3ce89 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Mon, 21 Dec 2020 13:01:38 +0100
Subject: [PATCH] install: remove -march=native

This simplifies the instructions. People interested in performance are
likely to know how to use it.
---
 INSTALL.md | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/INSTALL.md b/INSTALL.md
index 4bfef825..d553544f 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -157,17 +157,13 @@ optimization.
 In addition to being faster, PGO builds also tend to be smaller than
 regular `-O3` builds.
 
-**Note**: if you are packaging foot, you should probably remove
-`-march=native`, as that may cause gcc/clang to emit instructions that
-may not be available on other computers.
-
 
 #### Size optimized
 
 To optimize for size (i.e. produce a small binary):
 
 ```sh
-export CFLAGS="$CFLAGS -Os -march=native"
+export CFLAGS="$CFLAGS -Os"
 meson --buildtype=release --prefix=/usr -Db_lto=true ../..
 ninja
 ninja test
@@ -179,7 +175,7 @@ ninja install
 To do a regular, non-PGO build optimized for performance:
 
 ```sh
-export CFLAGS="$CFLAGS -O3 -march=native"
+export CFLAGS="$CFLAGS -O3"
 meson --buildtype=release --prefix=/usr -Db_lto=true ../..
 ninja
 ninja test
@@ -195,7 +191,7 @@ slower!) binary.
 First, configure the build directory:
 
 ```sh
-export CFLAGS="$CFLAGS -O3 -march=native -Wno-missing-profile"
+export CFLAGS="$CFLAGS -O3 -Wno-missing-profile"
 meson --buildtype=release --prefix=/usr -Db_lto=true ../..
 ```
 
@@ -205,7 +201,7 @@ later have a regression where PGO with `-O2` is **much** slower.
 If you are using Clang instead of GCC, use the following `CFLAGS` instead:
 
 ```sh
-export CFLAGS="$CFLAGS -O3 -march=native \
+export CFLAGS="$CFLAGS -O3 \
     -Wno-ignored-optimization-argument \
     -Wno-profile-instr-out-of-date \
     -Wno-profile-instr-unprofiled"