Don't cross allocators/deallocators

crates/engine_xetex/xetex/xetex-ext.c

@@ -659,11 +659,18 @@ loadOTfont(RawPlatformFontRef fontRef, XeTeXFont font, Fixed scaled_size, char*
     engine = createLayoutEngine(font, script, language,
                     features, nFeatures, shapers, rgbValue, extend, slant, embolden);
 
-    if (!engine) {
-        // only free these if creation failed, otherwise the engine now owns them
+    // The layout engine clones all these - this is temporary to avoid using
+    // different alloc/dealloc
+    if (features) {
         free(features);
+    }
+    if (shapers) {
         free(shapers);
-    } else {
+    }
+    if (language) {
+        free(language);
+    }
+    if (engine) {
         native_font_type_flag = OTGR_FONT_FLAG;
     }
 

crates/xetex_layout/src/c_api/engine.rs

@@ -107,12 +107,13 @@ impl XeTeXLayoutEngineBase {
         let font = Box::from_raw(font);
 
         let language = if !language.is_null() {
-            Some(Cow::Owned(CString::from_raw(language)))
+            Some(Cow::Owned(CStr::from_ptr(language).to_owned()))
         } else {
             None
         };
-        let features = if !features.is_null() {
-            Box::from_raw(ptr::slice_from_raw_parts_mut(features, n_features as usize))
+        let features: Box<[_]> = if !features.is_null() {
+            let len = n_features as usize;
+            Box::from(slice::from_raw_parts(features, len))
         } else {
             Box::new([])
         };
@@ -122,7 +123,7 @@ impl XeTeXLayoutEngineBase {
                 len += 1;
             }
             len += 1;
-            Vec::from_raw_parts(shapers, len, len)
+            slice::from_raw_parts(shapers, len).to_vec()
         } else {
             Vec::new()
         };