feat: succinct-zkvm std-lib support

Author: nhtyy

compiler/rustc_target/src/spec/targets/riscv32im_succinct_zkvm_elf.rs

@@ -10,7 +10,7 @@ pub(crate) fn target() -> Target {
             description: Some("Succinct's zero-knowledge Virtual Machine (RV32IM ISA)".into()),
             tier: Some(3),
             host_tools: Some(false),
-            std: None,
+            std: Some(true),
         },
         pointer_width: 32,
         arch: "riscv32".into(),

library/panic_abort/Cargo.toml

@@ -19,3 +19,10 @@ compiler_builtins = "0.1.0"
 
 [target.'cfg(not(all(windows, target_env = "msvc")))'.dependencies]
 libc = { version = "0.2", default-features = false }
+
+[lints.rust.unexpected_cfgs]
+level = "warn"
+check-cfg = [
+    'cfg(bootstrap)',
+    'cfg(target_os, values("succinct-zkvm"))'
+]

library/panic_abort/src/lib.rs

@@ -20,7 +20,7 @@
 #[cfg(target_os = "android")]
 mod android;
 
-#[cfg(target_os = "zkvm")]
+#[cfg(any(target_os = "zkvm", target_os = "succinct-zkvm"))]
 mod zkvm;
 
 use core::any::Any;
@@ -40,7 +40,7 @@ pub unsafe fn __rust_start_panic(_payload: &mut dyn PanicPayload) -> u32 {
     unsafe {
         android::android_set_abort_message(_payload);
     }
-    #[cfg(target_os = "zkvm")]
+    #[cfg(any(target_os = "zkvm", target_os = "succinct-zkvm"))]
     unsafe {
         zkvm::zkvm_set_abort_message(_payload);
     }

library/panic_abort/src/zkvm.rs

@@ -1,8 +1,7 @@
 use alloc::string::String;
 use core::panic::PanicPayload;
 
-// Forward the abort message to zkVM's sys_panic. This is implemented by RISC Zero's
-// platform crate which exposes system calls specifically for the zkVM.
+/// Note this function works with both `zkvm` and `succinct-zkvm`.
 pub(crate) unsafe fn zkvm_set_abort_message(payload: &mut dyn PanicPayload) {
     let payload = payload.get();
     let msg = match payload.downcast_ref::<&'static str>() {

library/std/Cargo.toml

@@ -163,4 +163,6 @@ check-cfg = [
     # and to the `backtrace` crate which messes-up with Cargo list
     # of declared features, we therefor expect any feature cfg
     'cfg(feature, values(any()))',
+    'cfg(target_os, values("succinct-zkvm"))'
 ]
+

library/std/build.rs

@@ -60,9 +60,9 @@ fn main() {
         || target_os == "uefi"
         || target_os == "teeos"
         || target_os == "zkvm"
+        || target_os == "succinct-zkvm"
         || target_os == "rtems"
         || target_os == "nuttx"
-
         // See src/bootstrap/src/core/build_steps/synthetic_targets.rs
         || env::var("RUSTC_BOOTSTRAP_SYNTHETIC_TARGET").is_ok()
     {

library/std/src/random.rs

@@ -48,6 +48,7 @@ use crate::sys::random as sys;
 /// VxWorks                | `randABytes` after waiting for `randSecure` to become ready
 /// WASI                   | [`random_get`](https://github.com/WebAssembly/WASI/blob/main/legacy/preview1/docs.md#-random_getbuf-pointeru8-buf_len-size---result-errno)
 /// ZKVM                   | `sys_rand`
+/// SUCCINCT-ZKVM          | `sys_rand` 
 ///
 /// Note that the sources used might change over time.
 ///

library/std/src/sys/alloc/mod.rs

@@ -7,7 +7,7 @@ use crate::ptr;
 // add fast paths for low alignment values.
 #[allow(dead_code)]
 const MIN_ALIGN: usize = if cfg!(any(
-    all(target_arch = "riscv32", any(target_os = "espidf", target_os = "zkvm")),
+    all(target_arch = "riscv32", any(target_os = "espidf", target_os = "zkvm", target_os = "succinct-zkvm")),
     all(target_arch = "xtensa", target_os = "espidf"),
 )) {
     // The allocator on the esp-idf and zkvm platforms guarantees 4 byte alignment.
@@ -89,7 +89,7 @@ cfg_if::cfg_if! {
         mod wasm;
     } else if #[cfg(target_os = "xous")] {
         mod xous;
-    } else if #[cfg(target_os = "zkvm")] {
+    } else if #[cfg(any(target_os = "zkvm", target_os = "succinct-zkvm"))] {
         mod zkvm;
     }
 }

library/std/src/sys/alloc/zkvm.rs

@@ -1,6 +1,7 @@
 use crate::alloc::{GlobalAlloc, Layout, System};
 use crate::sys::pal::abi;
 
+/// Note this allocator works with both `zkvm` and `succinct-zkvm`.
 #[stable(feature = "alloc_system_type", since = "1.28.0")]
 unsafe impl GlobalAlloc for System {
     #[inline]

library/std/src/sys/pal/mod.rs

@@ -64,6 +64,9 @@ cfg_if::cfg_if! {
     } else if #[cfg(target_os = "zkvm")] {
         mod zkvm;
         pub use self::zkvm::*;
+    } else if #[cfg(target_os = "succinct-zkvm")] {
+        mod succinct_zkvm;
+        pub use self::succinct_zkvm::*;
     } else {
         mod unsupported;
         pub use self::unsupported::*;