Try #1028:

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## **[Unreleased]**
 
+- [#1028](https://github.com/wasmerio/wasmer/pull/1028) Fix `get_wasi_version` when a module has multiple import namespaces.
 - [#1006](https://github.com/wasmerio/wasmer/pull/1006) Fix minor panic issue when `wasmer::compile_with` called with llvm backend
 - [#1009](https://github.com/wasmerio/wasmer/pull/1009) Enable LLVM verifier for all tests, add new llvm-backend-tests crate.
 - [#1004](https://github.com/wasmerio/wasmer/pull/1004) Add the Auto backend to enable to adapt backend usage depending on wasm file executed.

lib/wasi/src/utils.rs

@@ -18,24 +18,19 @@ pub enum WasiVersion {
 
 /// Detect the version of WASI being used from the namespace
 pub fn get_wasi_version(module: &Module) -> Option<WasiVersion> {
-    let mut import_iter = module
+    let namespace_table = &module.info().namespace_table;
+
+    module
         .info()
         .imported_functions
         .iter()
-        .map(|(_, import_name)| import_name.namespace_index);
+        .find_map(|(_, import_name)| {
+            let namespace_index = import_name.namespace_index;
 
-    // returns None if empty
-    let first = import_iter.next()?;
-    if import_iter.all(|idx| idx == first) {
-        // once we know that all the namespaces are the same, we can use it to
-        // detect which version of WASI this is
-        match module.info().namespace_table.get(first) {
-            "wasi_unstable" => Some(WasiVersion::Snapshot0),
-            "wasi_snapshot_preview1" => Some(WasiVersion::Snapshot1),
-            _ => None,
-        }
-    } else {
-        // not all funcs have the same namespace, therefore it's not WASI
-        None
-    }
+            match namespace_table.get(namespace_index) {
+                "wasi_unstable" => Some(WasiVersion::Snapshot0),
+                "wasi_snapshot_preview1" => Some(WasiVersion::Snapshot1),
+                _ => None,
+            }
+        })
 }