Apart from bumping the toolchain Clang's and port's version, this commit
completely overhauls the way LLVM toolchain is built.
First, it gets rid of a complicated two-stage process of first compiling
clang and compiler-rt builtins and then building libunwind, libc++abi,
and libc++ -- it is possible to create a complete cross-compilation
toolchain in a single CMake invocation with a modern LLVM. Moreover, the
old method was inherently unsupported and subtly broken.
Next, it utilizes full potential of the Stubs "framework". Now we are
even able to compile Clang with -Wl,-z,defs which makes one of the
patches obsolete and the whole installation less error-prone. Note that
it comes at a cost of complicating the bootstrap process on a completely
novel architecture but this hopefully won't happen often.
Lastly, it fixes handling of the -no*lib* family of flags in the
Serenity LLVM driver and correctly uses -nostartfiles in conjunction
with stubs to make necessary CMake configure-time checks succeed.
This commit adds minimal support for compiler-instrumentation based
memory access sanitization.
Currently we only support detection of kmalloc redzone accesses, and
kmalloc use-after-free accesses.
Support for inline checks (for improved performance), and for stack
use-after-return and use-after-return detection is left for future PRs.
I originally missed this while handling the upgrade to LLVM 15 (as it
only affects the on-serenity port), so the patch gets to be here with a
bit of a delay.
Co-Authored-By: sin-ack <sin-ack@users.noreply.github.com>
Add a patch to let llvm's InstrProfiling modules know serenity supports
all the Unix-y features required to make -fprofile-instr-generate and
-fcoverage-mapping work properly on target.
Besides a version bump, the following changes have been made to our
toolchain infrastructure:
- LLVM/Clang is now built with -march=native if the host compiler
supports it. An exception to this is CI, as the toolchain cache is
shared among many different machines there.
- The LLVM tarball is not re-extracted if the hash of the applied
patches doesn't differ.
- The patches have been split up into atomic chunks.
- Port-specific patches have been integrated into the main patches,
which will aid in the work towards self-hosting.
- <sysroot>/usr/local/lib is now appended to the linker's search path by
default.
- --pack-dyn-relocs=relr is appended to the linker command line by
default, meaning ports take advantage of RELR relocations without any
patches or additional compiler flags.
The formatting of LLVM port's package.sh has been bothering me, so I
also indented the arguments to the CMake invocation.
