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Sourav

Member

From: India

Registered: 2019-04-22

Posts: 84

Website

[Solved] CC and CXX flags are ignored by makepkg

I am trying to compile linux-xanmod with Clang 10.
Whenever I run

makepkg -sir

I get to see cc1 is running.

My /etc/makepkg.conf is:

#!/hint/bash
#
# /etc/makepkg.conf
#

#########################################################################
# SOURCE ACQUISITION
#########################################################################
#
#-- The download utilities that makepkg should use to acquire sources
#  Format: 'protocol::agent'
DLAGENTS=('file::/usr/bin/curl -gqC - -o %o %u'
          'ftp::/usr/bin/curl -gqfC - --ftp-pasv --retry 3 --retry-delay 3 -o %o %u'
          'http::/usr/bin/curl -gqb "" -fLC - --retry 3 --retry-delay 3 -o %o %u'
          'https::/usr/bin/curl -gqb "" -fLC - --retry 3 --retry-delay 3 -o %o %u'
          'rsync::/usr/bin/rsync --no-motd -z %u %o'
          'scp::/usr/bin/scp -C %u %o')

# Other common tools:
# /usr/bin/snarf
# /usr/bin/lftpget -c
# /usr/bin/wget

#-- The package required by makepkg to download VCS sources
#  Format: 'protocol::package'
VCSCLIENTS=('bzr::bzr'
            'git::git'
            'hg::mercurial'
            'svn::subversion')

#########################################################################
# ARCHITECTURE, COMPILE FLAGS
#########################################################################
#

CARCH="x86_64"
CHOST="x86_64-pc-linux-gnu"

#-- Compiler
export CC=clang
export CXX=clang++

#-- Compiler and Linker Flags
CPPFLAGS="-D_FORTIFY_SOURCE=2"
CFLAGS="-march=x86-64 -mtune=generic -O2 -pipe -fno-plt -mllvm -vectorize-loops"
CXXFLAGS="-march=x86-64 -mtune=generic -O2 -pipe -fno-plt -mllvm -vectorize-loops"
LDFLAGS="-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now"
#RUSTFLAGS="-C opt-level=2"
#-- Make Flags: change this for DistCC/SMP systems
MAKEFLAGS="-j3"
#-- Debugging flags
#DEBUG_CFLAGS="-g -fvar-tracking-assignments"
#DEBUG_CXXFLAGS="-g -fvar-tracking-assignments"
#DEBUG_RUSTFLAGS="-C debuginfo=2"

#########################################################################
# BUILD ENVIRONMENT
#########################################################################
#
# Defaults: BUILDENV=(!distcc !color !ccache check !sign)
#  A negated environment option will do the opposite of the comments below.
#
#-- distcc:   Use the Distributed C/C++/ObjC compiler
#-- color:    Colorize output messages
#-- ccache:   Use ccache to cache compilation
#-- check:    Run the check() function if present in the PKGBUILD
#-- sign:     Generate PGP signature file
#
BUILDENV=(!distcc color !ccache check !sign)
#
#-- If using DistCC, your MAKEFLAGS will also need modification. In addition,
#-- specify a space-delimited list of hosts running in the DistCC cluster.
#DISTCC_HOSTS=""
#
#-- Specify a directory for package building.
#BUILDDIR=/tmp/makepkg

#########################################################################
# GLOBAL PACKAGE OPTIONS
#   These are default values for the options=() settings
#########################################################################
#
# Default: OPTIONS=(!strip docs libtool staticlibs emptydirs !zipman !purge !debug)
#  A negated option will do the opposite of the comments below.
#
#-- strip:      Strip symbols from binaries/libraries
#-- docs:       Save doc directories specified by DOC_DIRS
#-- libtool:    Leave libtool (.la) files in packages
#-- staticlibs: Leave static library (.a) files in packages
#-- emptydirs:  Leave empty directories in packages
#-- zipman:     Compress manual (man and info) pages in MAN_DIRS with gzip
#-- purge:      Remove files specified by PURGE_TARGETS
#-- debug:      Add debugging flags as specified in DEBUG_* variables
#
OPTIONS=(strip docs !libtool !staticlibs emptydirs zipman purge !debug)

#-- File integrity checks to use. Valid: md5, sha1, sha224, sha256, sha384, sha512, b2
INTEGRITY_CHECK=(md5)
#-- Options to be used when stripping binaries. See `man strip' for details.
STRIP_BINARIES="--strip-all"
#-- Options to be used when stripping shared libraries. See `man strip' for details.
STRIP_SHARED="--strip-unneeded"
#-- Options to be used when stripping static libraries. See `man strip' for details.
STRIP_STATIC="--strip-debug"
#-- Manual (man and info) directories to compress (if zipman is specified)
MAN_DIRS=({usr{,/local}{,/share},opt/*}/{man,info})
#-- Doc directories to remove (if !docs is specified)
DOC_DIRS=(usr/{,local/}{,share/}{doc,gtk-doc} opt/*/{doc,gtk-doc})
#-- Files to be removed from all packages (if purge is specified)
PURGE_TARGETS=(usr/{,share}/info/dir .packlist *.pod)
#-- Directory to store source code in for debug packages
DBGSRCDIR="/usr/src/debug"

#########################################################################
# PACKAGE OUTPUT
#########################################################################
#
# Default: put built package and cached source in build directory
#
#-- Destination: specify a fixed directory where all packages will be placed
#PKGDEST=/home/packages
#-- Source cache: specify a fixed directory where source files will be cached
#SRCDEST=/home/sources
#-- Source packages: specify a fixed directory where all src packages will be placed
#SRCPKGDEST=/home/srcpackages
#-- Log files: specify a fixed directory where all log files will be placed
#LOGDEST=/home/makepkglogs
#-- Packager: name/email of the person or organization building packages
#PACKAGER="John Doe <john@doe.com>"
#-- Specify a key to use for package signing
#GPGKEY=""

#########################################################################
# COMPRESSION DEFAULTS
#########################################################################
#
COMPRESSGZ=(gzip -c -f -n)
COMPRESSBZ2=(bzip2 -c -f)
COMPRESSXZ=(xz -c -z -)
COMPRESSZST=(zstd -c -z -q -)
COMPRESSLRZ=(lrzip -q)
COMPRESSLZO=(lzop -q)
COMPRESSZ=(compress -c -f)
COMPRESSLZ4=(lz4 -q)
COMPRESSLZ=(lzip -c -f)

#########################################################################
# EXTENSION DEFAULTS
#########################################################################
#
PKGEXT='.pkg.tar.xz'
SRCEXT='.src.tar.gz'

I am also seeing gcc warnings about

-mllvm -vectorize-loops

But I am eager to benchmark using Clang. Why is makepkg.conf ignoring clang?

Last edited by Sourav (2020-09-01 20:56:40)

Trilby

Inspector Parrot

Registered: 2011-11-29

Posts: 30,456

Website

Re: [Solved] CC and CXX flags are ignored by makepkg

I see no evidence that makepkg is ignoring your setting - but it's not magic.  The makefile from upstream overrides CC to be gcc unless LLVM is set.

Last edited by Trilby (2020-09-01 20:43:03)

---

"UNIX is simple and coherent" - Dennis Ritchie; "GNU's Not Unix" - Richard Stallman

Sourav

Member

From: India

Registered: 2019-04-22

Posts: 84

Website

Re: [Solved] CC and CXX flags are ignored by makepkg

Thanks a lot! I saw that

src/linux-5.8/Makefile

has this code:

ifneq ($(LLVM),)
HOSTCC  = clang
HOSTCXX = clang++
else
HOSTCC  = gcc
HOSTCXX = g++
endif

And some similar ones below...

So, I just used this command:

LLVM=true makepkg -c --noprepare    # LLVM=1 or something like that should also work

Oh and I also had to install

lld

And it's compiling with clang!

Last edited by Sourav (2020-09-01 20:59:12)

loqs

Member

Registered: 2014-03-06

Posts: 18,859

Re: [Solved] CC and CXX flags are ignored by makepkg

You did not find https://aur.archlinux.org/packages/linux-llvm/ ?

Sourav

Member

From: India

Registered: 2019-04-22

Posts: 84

Website

Re: [Solved] CC and CXX flags are ignored by makepkg

Xanmod gives me a significant performance boost, about 20% - 30% more in app launches and a huge performance in games like Xonotic. So I use the Xanmod kernel by default. Wanted to give it a shot by compiling with clang. I also disabled AMD CPU support, and GFS2, JFS support that I will never use in the future... Let's see if it gets any faster and light weight...

Sourav

Member

From: India

Registered: 2019-04-22

Posts: 84

Website

Re: [Solved] CC and CXX flags are ignored by makepkg

I have managed to compile and boot the system, working as fast as before, nothing changed, but I have debloated 50 MB by disabling AMD support and some other stuff...

But the problem I always face is with clang compiled kernel, dkms modules can't be installed for whatever reason. I have to go back and compile with GCC. It's the case till now...

I need v4l2loopback and virtualbox support. So...

guglovich

Member

Registered: 2021-07-01

Posts: 8

Re: [Solved] CC and CXX flags are ignored by makepkg

Xanmod gives me a significant performance boost, about 20% - 30% more in app launches and a huge performance in games like Xonotic. So I use the Xanmod kernel by default. Wanted to give it a shot by compiling with clang. I also disabled AMD CPU support, and GFS2, JFS support that I will never use in the future... Let's see if it gets any faster and light weight...

I wonder how you do it or what kind of iron. My gain from changing cores is 2 fps at most )

2ManyDogs

Forum Fellow

Registered: 2012-01-15

Posts: 4,648

Re: [Solved] CC and CXX flags are ignored by makepkg

guglovich, this thread is two years old and marked solved. Please do not necrobump.

Closing.