# Patches for llvm on Minerva

## `0001-clang-Add-support-for-Minerva.patch`

Add support for Minerva

Adds support for the `$arch-pc-minerva` target to the Clang front end.
This makes the compiler look for libraries and headers in the right
places, and enables some security mitigations like stack-smashing
protection and position-independent code by default.

Co-authored-by: kleines Filmröllchen <filmroellchen@serenityos.org>
Co-authored-by: Andrew Kaster <akaster@serenityos.org>
Co-authored-by: Daniel Bertalan <dani@danielbertalan.dev>
Co-authored-by: Dan Klishch <danilklishch@gmail.com>

## `0002-llvm-Add-support-for-building-LLVM-on-Minerva.patch`

Add support for building LLVM on Minerva

Adds Minerva `#ifdef`s for platform-specific code.

We stub out wait4, as Minerva doesn't support querying a child
process's resource usage information.

POSIX shm is not supported by Minerva yet, so disable it in Orc.

Minerva gives each thread a default of 1MiB of stack. Increase the
default stack size for llvm applications when running on Minerva.


## `0003-tools-Support-building-shared-libLLVM-and-libClang-f.patch`

Support building shared libLLVM and libClang for Minerva

This patch tells CMake that the --whole-archive linker option should be
used for specifying the archives whose members will constitute these
shared libraries.

Symbol versioning is disabled, as the Minerva loader doesn't support
it, and the ELF sections that store version data would just waste space.

## `0004-compiler-rt-Enable-profile-instrumentation-for-Seren.patch`

Enable profile instrumentation for Minerva

Treat Minerva the same as other *NIX platforms that behave close
enough to linux to use the pre-canned InstrProfiling implementation.

## `0005-libcxx-Add-support-for-Minerva.patch`

Add support for Minerva

This commit teaches libc++ about what features are available in our
LibC, namely:
* We do not have locale support, so no-op shims should be used in place
  of the C locale API.
* The number of errno constants defined by us is given by the value of
  the `ELAST` macro.
* Multithreading is implemented though the pthread library.
* Use libc++'s builtin character type table instead of the one provided
  by LibC as there's a lot of extra porting work to convince the rest of
  locale.cpp to use our character type table properly.

## `0006-RISCV-Implement-__init_riscv_feature_bits-for-Sereni.patch`

Implement __init_riscv_feature_bits for Minerva

The Minerva dynamic linker provides a magic function
"__get_riscv_feature_bits" that populates __riscv_feature_bits
and __riscv_cpu_model.