Support native simulator.

[zhang-wenchao]

https://docs.zephyrproject.org/latest/boards/native/native_sim/doc/index.html

[zhang-wenchao]

Rust llvm target x86_64-unknown-none，I actually tested it and it works.

[zhang-wenchao]

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 582e14a..26bf03d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -47,7 +47,8 @@ function(_rust_map_target)
message(FATAL_ERROR "Rust: Unsupported riscv ISA")
endif()
else()
-    message(FATAL_ERROR "Rust: Add support for other target")
+      set(RUST_TARGET "x86_64-unknown-none" PARENT_SCOPE)
+#    message(FATAL_ERROR "Rust: Add support for other target")
endif()
endfunction()

diff --git a/Kconfig b/Kconfig
index 9a3ed88..4c44422 100644
--- a/Kconfig
+++ b/Kconfig
@@ -8,7 +8,7 @@ menu "Rust Language Support"
config RUST_SUPPORTED
bool
default y if (CPU_CORTEX_M || \
-               (RISCV && !RISCV_ISA_RV32E && !RISCV_ISA_RV128I))
+               (RISCV && !RISCV_ISA_RV32E && !RISCV_ISA_RV128I) || ARCH_POSIX)
help
Selected for platforms that have support for Rust.

west build -p always -b native_sim/native/64

I'm trying to figure out how to support and Rust target.

[d3zd3z]

Any idea how well the various tests work?

[zhang-wenchao]

native_sim/native/64 with x86_64-unknown-none No problem.

native_sim with i686-unknown-linux-gnu or i686-unknown-linux-musl there is a compilation error.

FAILED: zephyr/CMakeFiles/native_runner_executable zephyr/zephyr.exe /home/life/Develop/job/my/embedded/ohw-nano/build/zephyr/CMakeFiles/native_runner_executable /home/life/Develop/job/my/embedded/ohw-nano/build/zephyr/zephyr.exe 
cd /home/life/Develop/job/my/embedded/ohw-nano/build/zephyr && /usr/bin/make -f /home/life/Develop/platform/zephyr-project/zephyr/scripts/native_simulator/Makefile all --warn-undefined-variables -r NSI_CONFIG_FILE=/home/life/Develop/job/my/embedded/ohw-nano/build/zephyr/NSI/nsi_config
/usr/bin/ld: /home/life/Develop/job/my/embedded/ohw-nano/build/zephyr/NSI/home/life/Develop/job/my/embedded/ohw-nano/build/zephyr/zephyr.elf.loc_cpusw.o:(.data.DW.ref.rust_eh_personality[DW.ref.rust_eh_personality]+0x0): undefined reference to `rust_eh_personality'
collect2: error: ld returned 1 exit status

I hacked it and it works fine.

#[no_mangle]
extern "C" fn rust_eh_personality() {}

there are no other problems, but I don't know how to integrate it better. So there is no pr.

[zhang-wenchao]

I also briefly tested the esp series chips and there were no problems.

The esp chip involves the esp toolchain, and the addition of the native simulator does not involve anything else.

In fact, supporting esp chips only requires a small modification after enabling the esp rust toolchain.

config RUST_SUPPORTED
        bool
        default y if ((CPU_CORTEX_M || \
                                (RISCV && !RISCV_ISA_RV32E && !RISCV_ISA_RV128I) || SOC_SERIES_ESP32S3) && \
                                !TIMER_READS_ITS_FREQUENCY_AT_RUNTIME)
        help
          Selected for platforms that have support for Rust.

elseif(CONFIG_SOC_ESP32S3)
  set(RUST_TARGET "xtensa-esp32s3-none-elf" PARENT_SCOPE)


cargo +esp build -Z build-std=core,alloc

[d3zd3z]

Also, ARCH_POSIX doesn't imply x86. But, we should at least be able to narrow it down a bit, perhaps x86-64, i686 (x86-32), and arm64? That would cover most Linux and Mac machines.

I'll be real curious if the embassy executor I've added will work. As long as k_thread_suspend and k_thread_resume work, as well as timers, this should be fine.

[kamathba]

x86_64-unknown-linux-gnu also works, so long as you conditionally don't overwrite the panic handler in the zephyr crate and change samples to use std. e.g.

-#![no_std]
+#![cfg_attr(not(CONFIG_BOARD_NATIVE_SIM), no_std)]

Part of me thinks targets with std support might be better for native_sim since I think you'd still be able to develop no_std crates / applications, but allow yourself to make simulation backends and stuff using std, but maybe it feels a little messy.

This issue was vaguely worded but I think to some level though it is done/landed, yes?