Interpret system call numbers relative to target architecture

Author: Aaron1011

src/fn_call.rs

@@ -216,9 +216,9 @@ pub trait EvalContextExt<'a, 'mir, 'tcx: 'a + 'mir>: crate::MiriEvalContextExt<'
                 //
                 // `libc::syscall(NR_GETRANDOM, buf.as_mut_ptr(), buf.len(), GRND_NONBLOCK)`
                 // is called if a `HashMap` is created the regular way (e.g. HashMap<K, V>).
-                match this.read_scalar(args[0])?.to_usize(this)? as i64 {
+                match (this.read_scalar(args[0])?.to_usize(this)? as i64, tcx.data_layout.pointer_size.bits()) {
                     // SYS_getrandom on x86_64 and x86 respectively
-                    318 | 355 => {
+                    (318, 64) | (355, 32) => {
                         let ptr = this.read_scalar(args[1])?.to_ptr()?;
                         let len = this.read_scalar(args[2])?.to_usize(this)?;
 
@@ -232,7 +232,7 @@ pub trait EvalContextExt<'a, 'mir, 'tcx: 'a + 'mir>: crate::MiriEvalContextExt<'
 
                         this.write_scalar(Scalar::from_uint(len, dest.layout.size), dest)?;
                     }
-                    id => {
+                    (id, _size) => {
                         return err!(Unimplemented(
                             format!("miri does not support syscall ID {}", id),
                         ))