Re: [Linux-v5.17-rc6] Building tools/perf with perl v5.34

From: Jiri Olsa
Date: Sun Mar 06 2022 - 10:42:27 EST


On Sun, Mar 06, 2022 at 03:28:09AM +0100, Sedat Dilek wrote:
> On Sat, Mar 5, 2022 at 9:09 PM Jiri Olsa <olsajiri@xxxxxxxxx> wrote:
> >
> > On Sat, Mar 05, 2022 at 08:52:18AM +0100, Sedat Dilek wrote:
> > > Hi,
> > >
> > > I am here on Debian/unstable AMD64 which switched over to perl v5.34
> > > in February 2022.
> > >
> > > Unfortunately, my perf does not build with this (lib)perl version:
> > >
> > > $ ~/bin/perf -vv
> > > perf version 5.17-rc6
> > > dwarf: [ on ] # HAVE_DWARF_SUPPORT
> > > dwarf_getlocations: [ on ] # HAVE_DWARF_GETLOCATIONS_SUPPORT
> > > glibc: [ on ] # HAVE_GLIBC_SUPPORT
> > > syscall_table: [ on ] # HAVE_SYSCALL_TABLE_SUPPORT
> > > libbfd: [ on ] # HAVE_LIBBFD_SUPPORT
> > > libelf: [ on ] # HAVE_LIBELF_SUPPORT
> > > libnuma: [ on ] # HAVE_LIBNUMA_SUPPORT
> > > numa_num_possible_cpus: [ on ] # HAVE_LIBNUMA_SUPPORT
> > > libperl: [ OFF ] # HAVE_LIBPERL_SUPPORT
> > > libpython: [ on ] # HAVE_LIBPYTHON_SUPPORT
> > > libslang: [ on ] # HAVE_SLANG_SUPPORT
> > > libcrypto: [ on ] # HAVE_LIBCRYPTO_SUPPORT
> > > libunwind: [ on ] # HAVE_LIBUNWIND_SUPPORT
> > > libdw-dwarf-unwind: [ on ] # HAVE_DWARF_SUPPORT
> > > zlib: [ on ] # HAVE_ZLIB_SUPPORT
> > > lzma: [ on ] # HAVE_LZMA_SUPPORT
> > > get_cpuid: [ on ] # HAVE_AUXTRACE_SUPPORT
> > > bpf: [ on ] # HAVE_LIBBPF_SUPPORT
> > > aio: [ on ] # HAVE_AIO_SUPPORT
> > > zstd: [ on ] # HAVE_ZSTD_SUPPORT
> > > libpfm4: [ OFF ] # HAVE_LIBPFM
> > >
> > > $ grep libperl ../make-log_perf-python3.10-install_bin.txt
> > > 9:Makefile.config:788: Missing perl devel files. Disabling perl
> > > scripting support, please install perl-ExtUtils-Embed/libperl-dev
> > > 22:... libperl: [ OFF ]
> > >
> > > Checking for these requirements:
> > >
> > > # dpkg -l | grep perl | grep 5.34 | awk '/^ii/ {print $1 " " $2 " "
> > > $3}' | column -t
> > > ii libperl-dev:amd64 5.34.0-3
> > > ii libperl5.34:amd64 5.34.0-3
> > > ii perl 5.34.0-3
> > > ii perl-base 5.34.0-3
> > > ii perl-modules-5.34 5.34.0-3
> > >
> > > # dpkg -L perl-modules-5.34 | grep -i ExtUtils | grep -i Embed
> > > /usr/share/perl/5.34.0/ExtUtils/Embed.pm
> > >
> > > Can you please comment on this?
> >
> > hi,
> > is there something in tools/build/feature/test-libperl.make.output ?
> >
>
> Hey jirka!
>
> Indeed there is such a file.
>
> $ LC_ALL=C ll tools/build/feature/test-libperl.make.output
> -rw-r--r-- 1 dileks dileks 24K Mar 6 03:22
> tools/build/feature/test-libperl.make.output
>
> Reproducer:
>
> make distclean
> make -C tools/perf clean
>
> MAKE="make"
> MAKE_OPTS="HOSTCC=clang-13 HOSTCXX=clang++-13 HOSTLD=ld.lld-13
> HOSTAR=llvm-ar-13 CC=clang-13 LD=ld.lld-13 AR=llvm-ar-13 NM=llvm-nm-13
> OBJCOPY=llvm-objcopy-13 OBJDUMP=llvm-objdump-13 OBJSIZE=llvm-size-13
> READELF=llvm-readelf-13 STRIP=llvm-strip-13 LLVM_IAS=1"
>
> LC_ALL=C $MAKE V=1 $MAKE_OPTS -C tools/perf PYTHON=python3 install-bin

yea, looks like we can't compile perl devel includes with clang,
we use simple perl test program:

$ cd tools/build/feature/
$ cat test-libperl.c
// SPDX-License-Identifier: GPL-2.0
#include <EXTERN.h>
#include <perl.h>

int main(void)
{
perl_alloc();

return 0;
}


and if I compile it with:

$ CC=clang make test-libperl.bin
clang -MD -Wall -Werror -o test-libperl.bin test-libperl.c > test-libperl.make.output 2>&1 `perl -MExtUtils::Embed -e ccopts 2>/dev/null` -Wl,--enable-new-dtags -Wl,-z,relro -Wl,--as-needed -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -Wl,-z,relro -Wl,--as-needed -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -fstack-protector-strong -L/usr/local/lib -L/usr/lib64/perl5/CORE -lperl -lpthread -lresolv -ldl -lm -lcrypt -lutil -lc
make: *** [Makefile:224: test-libperl.bin] Error 1


I'm getting some other lto related error:

$ cat test-libperl.make.output
clang-13: error: optimization flag '-ffat-lto-objects' is not supported [-Werror,-Wignored-optimization-argument]


with my clang version:

$ clang --version
clang version 13.0.0 (Fedora 13.0.0-3.fc35)
Target: x86_64-redhat-linux-gnu
Thread model: posix
InstalledDir: /usr/bin

so you need to figure out how to compile the test program
above first with clang

jirka