Free the memory the Swift runtime allocated in swift_getTypeName().

Author: DougGregor

JavaSwiftKitDemo/src/main/java/org/swift/javakit/SwiftKit.java

@@ -63,6 +63,36 @@ static MemorySegment findOrThrow(String symbol) {
                 .orElseThrow(() -> new UnsatisfiedLinkError("unresolved symbol: %s".formatted(symbol)));
     }
 
+    // ==== ------------------------------------------------------------------------------------------------------------
+    // free
+    /**
+     * Descriptor for the free C runtime function.
+     */
+    public static final FunctionDescriptor free$descriptor = FunctionDescriptor.ofVoid(
+        ValueLayout.ADDRESS
+    );
+
+    /**
+     * Address of the free C runtime function.
+     */
+    public static final MemorySegment free$addr = findOrThrow("free");
+
+    /**
+     * Handle for the free C runtime function.
+     */
+    public static final MethodHandle free$handle = Linker.nativeLinker().downcallHandle(free$addr, free$descriptor);
+
+    /**
+     * free the given pointer
+     */
+    public static void cFree(MemorySegment pointer) {
+        try {
+            free$handle.invokeExact(pointer);
+        } catch (Throwable ex$) {
+            throw new AssertionError("should not reach here", ex$);
+        }
+    }
+
     // ==== ------------------------------------------------------------------------------------------------------------
     // swift_retainCount
 
@@ -383,7 +413,9 @@ public static String nameOfSwiftType(MemorySegment typeMetadata, boolean qualifi
             try (Arena arena = Arena.ofConfined()) {
               MemorySegment charsAndLength = (MemorySegment)swift_getTypeName$handle.invokeExact((SegmentAllocator)arena, typeMetadata, qualified);
               MemorySegment utf8Chars = charsAndLength.get(SWIFT_POINTER, 0);
-              return utf8Chars.getString(0);
+              String typeName = utf8Chars.getString(0);
+              cFree(utf8Chars);
+              return typeName;
             }
         } catch (Throwable ex$) {
             throw new AssertionError("should not reach here", ex$);