Use a 'flags' parameter instead of 'version'

README.md

@@ -290,7 +290,7 @@ extern "Rust" {
     ///
     /// The fields must be declared in exactly the same order as they appear in `MiriFrame` above.
     /// This function can be called on any thread (not just the one which obtained `frame`)
-    fn miri_resolve_frame(version: u8, frame: *mut ()) -> MiriFrame;
+    fn miri_resolve_frame(frame: *mut (), flags: u64) -> MiriFrame;
 
     /// Miri-provided extern function to begin unwinding with the given payload.
     ///

src/shims/foreign_items.rs

@@ -251,11 +251,11 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
             // Resolves a Miri backtrace frame. See the README for details.
             "miri_resolve_frame" => {
                 let tcx = this.tcx;
-                let &[version, ptr] = check_arg_count(args)?;
+                let &[ptr, flags] = check_arg_count(args)?;
 
-                let version = this.read_scalar(version)?.to_u8()?;
-                if version != 0 {
-                    throw_ub_format!("Unknown `miri_resolve_frame` version {}", version);
+                let flags = this.read_scalar(flags)?.to_u64()?;
+                if flags != 0 {
+                    throw_ub_format!("Unknown `miri_resolve_frame` flags {}", flags);
                 }
 
                 let ptr = match this.read_scalar(ptr)?.check_init()? {

tests/compile-fail/backtrace/bad-backtrace-decl.rs

@@ -1,13 +1,13 @@
 extern "Rust" {
     fn miri_get_backtrace() -> Box<[*mut ()]>;
-    fn miri_resolve_frame(version: u8, ptr: *mut ());
+    fn miri_resolve_frame(ptr: *mut (), flags: u64);
 }
 
 fn main() {
     let frames = unsafe { miri_get_backtrace() };
     for frame in frames.into_iter() {
         unsafe {
-            miri_resolve_frame(0, *frame); //~ ERROR Undefined Behavior: Bad declaration of miri_resolve_frame - should return a struct with 4 fields
+            miri_resolve_frame(*frame, 0); //~ ERROR Undefined Behavior: Bad declaration of miri_resolve_frame - should return a struct with 4 fields
         }
     }
 }

tests/compile-fail/backtrace/bad-backtrace-ptr.rs

@@ -1,9 +1,9 @@
 extern "Rust" {
-    fn miri_resolve_frame(version: u8, ptr: *mut ());
+    fn miri_resolve_frame(ptr: *mut (), flags: u64);
 }
 
 fn main() {
     unsafe {
-        miri_resolve_frame(0, 0 as *mut _); //~ ERROR Undefined Behavior: Expected a pointer
+        miri_resolve_frame(0 as *mut _, 0); //~ ERROR Undefined Behavior: Expected a pointer
     }
 }

tests/compile-fail/backtrace/bad-backtrace-version.rs

@@ -1,9 +1,9 @@
 extern "Rust" {
-    fn miri_resolve_frame(version: u8, ptr: *mut ());
+    fn miri_resolve_frame(ptr: *mut (), flags: u64);
 }
 
 fn main() {
     unsafe {
-        miri_resolve_frame(1, 0 as *mut _); //~ ERROR  Undefined Behavior: Unknown `miri_resolve_frame` version 1
+        miri_resolve_frame(0 as *mut _, 1); //~ ERROR  Undefined Behavior: Unknown `miri_resolve_frame` flags 1
     }
 }

tests/run-pass/backtrace-api.rs

@@ -3,7 +3,7 @@
 
 extern "Rust" {
     fn miri_get_backtrace() -> Box<[*mut ()]>;
-    fn miri_resolve_frame(version: u8, ptr: *mut ()) -> MiriFrame;
+    fn miri_resolve_frame(ptr: *mut (), flags: u64) -> MiriFrame;
 }
 
 #[derive(Debug)]
@@ -17,7 +17,7 @@ struct MiriFrame {
 fn main() {
     let frames = unsafe { miri_get_backtrace() };
     for frame in frames.into_iter() {
-        let miri_frame = unsafe { miri_resolve_frame(0, *frame) };
+        let miri_frame = unsafe { miri_resolve_frame(*frame, 0) };
         let name = String::from_utf8(miri_frame.name.into()).unwrap();
         let filename = String::from_utf8(miri_frame.filename.into()).unwrap();
         eprintln!("{}:{}:{} ({})", filename, miri_frame.lineno, miri_frame.colno, name);