This is the seventh post in my toolchains adventures series. Please check
the previous posts in the toolchains category for more context about
this journey. There was no Q4 2022 report as there wasn't really anything
worthwhile to write about, only some usual Pkgsrc and OpenBSD toolchains
related ports updates.
In Pkgsrc land, I updated binutils to the 2.40 version, mold to the
1.9.0, 1.10.0, 1.10.1, and 1.11.0 versions, patchelf
to the 0.17.2 version, and finally pax-utils to the 1.3.6 and
the 1.3.7 ones. I also updated the NetBSD system call table in GDB
to add the eventfd(2) and timerfd(2) syscalls which were added back in 2021.
Regarding OpenBSD, I updated binutils to the 2.40 version and enabled
the build of gas, for which I also pushed support for ARM upstream. While
there, I added support upstream for the PT_OPENBSD_MUTABLE segment type
to readelf. Lastly, I packaged and imported pax-utils into the ports
collection.
In early February, I attended FOSDEM 2023 in Brussels and had the
opportunity to attend some talks in the LLVM devroom as well as some
toolchains related ones in the RISC-V and Binary Tools devrooms.
Lately, I've been exploring using alternative linkers in Pkgsrc. By default,
the host system default linker will be used, which happens to be GNU ld
on NetBSD and most Linux distributions.
Thanks to work done by pho@ and the instructions he posted on the
tech-pkg mailing list, it was already possible to use mold within
Pkgsrc, by adding these directives in the etc/mk.conf configuration file:
LD= /usr/pkg/bin/mold
LDFLAGS+= -Wl,-L/usr/lib
CWRAPPERS_PREPEND.cc+= -B/usr/pkg/libexec/mold
CWRAPPERS_PREPEND.cxx+= -B/usr/pkg/libexec/mold
I wanted to also try using LLD (the LLVM linker), and modified the
devel/lld package to add a symlink in ${PREFIX}/libexec so that it
can be used in Pkgsrc.
While mold can be used as a linker when using both GCC and Clang, for LLD
one must use Clang as a compiler, using the PKGSRC_COMPILER directive.
The reason for this is that LLD does not support the -dc and -dp options.
The following directives must be added in the etc/mk.conf configuration
file:
PKGSRC_COMPILER= clang
LD= /usr/pkg/bin/lld
LDFLAGS+= -Wl,-L/usr/lib
CWRAPPERS_PREPEND.cc+= -B/usr/pkg/libexec/lld
CWRAPPERS_PREPEND.cxx+= -B/usr/pkg/libexec/lld
Verifying that a binary was produced by mold or LLD can be done using
readelf.
On the mold binary linked with mold itself:
readelf -p .comment mold
String dump of section '.comment':
[ 0] mold 1.10.1 (compatible with GNU ld)
[ 25] GCC: (NetBSD nb1 20220722) 10.4.0
[ 47] GCC: (nb1 20220722) 10.4.0
And on the lld binary linked with LLD itself:
readelf -p .comment lld
String dump of section '.comment':
[ 0] clang version 15.0.7
[ 16] Linker: LLD 15.0.7
[ 29] GCC: (NetBSD nb1 20220722) 10.4.0
As usual, Iāve also been busy reading different material, and adding new
resources to toolchains.net.
Thatās all for now, happy Spring 2023 everyone!
binutils and GDB commits:
| | |
|---|
| 2023-03-23 | 80251d4 | Add support to readelf for the PT_OPENBSD_MUTABLE segment type |
| 2023-03-17 | 152d9c4 | Update the NetBSD system call table to add eventfd(2) and timerfd(2) |
| 2023-01-20 | 2e17538 | Add OpenBSD ARM GAS support |
LLVM commits
| | |
|---|
| 2023-03-19 | 8510cf9 | [compiler-rt] Add missing #else clause to fix the build on NetBSD |
| 2023-03-16 | 245f26a | [docs] Document "PGO" (Profile-Guided Optimization) in the lexicon |
| 2023-03-15 | d8df871 | [compiler-rt] Point UndefinedBehaviorSanitizer link to its own page |
| 2023-02-10 | 5cec69b | [clang] Update Clang version from 16 to 17 in scan-build.1 |
![[link]](https://i.ibb.co/vcqD1DJ/netbsd-screen.png){kind=link}