fixed C bit field thing

Author: sliemeobn

Sources/JavaScriptKit/FundamentalObjects/JSFunction.swift

@@ -137,10 +137,8 @@ public class JSFunction: JSObject, _JSFunctionProtocol {
                 id, argv, Int32(argc),
                 &payload1, &payload2
             )
-            let kindAndFlags = unsafeBitCast(resultBitPattern, to: JavaScriptValueKindAndFlags.self)
-            #if !hasFeature(Embedded)
+            let kindAndFlags = valueKindAndFlagsFromBits(resultBitPattern)
             assert(!kindAndFlags.isException)
-            #endif
             let result = RawJSValue(kind: kindAndFlags.kind, payload1: payload1, payload2: payload2)
             return result
         }
@@ -156,7 +154,7 @@ public class JSFunction: JSObject, _JSFunctionProtocol {
                 id, argv, Int32(argc),
                 &payload1, &payload2
             )
-            let kindAndFlags = unsafeBitCast(resultBitPattern, to: JavaScriptValueKindAndFlags.self)
+            let kindAndFlags = valueKindAndFlagsFromBits(resultBitPattern)
             #if !hasFeature(Embedded)
             assert(!kindAndFlags.isException)
             #endif
@@ -241,4 +239,25 @@ public extension _JSFunctionProtocol {
         new(arguments: [arg0.jsValue, arg1.jsValue, arg2.jsValue, arg3.jsValue, arg4.jsValue, arg5.jsValue, arg6.jsValue])
     }
 }
-#endif
+
+// C bit fields seem to not work with Embedded
+// in "normal mode" this is defined as a C struct
+private struct JavaScriptValueKindAndFlags {
+    let errorBit: UInt32 = 1 << 32
+    let kind: JavaScriptValueKind
+    let isException: Bool
+
+    init(bitPattern: UInt32) {
+        self.kind = JavaScriptValueKind(rawValue: bitPattern & ~errorBit)!
+        self.isException = (bitPattern & errorBit) != 0
+    }
+}
+#endif
+
+private func valueKindAndFlagsFromBits(_ bits: UInt32) -> JavaScriptValueKindAndFlags {
+    #if hasFeature(Embedded)
+    JavaScriptValueKindAndFlags(bitPattern: bits)
+    #else 
+    unsafeBitCast(resultBitPattern, to: JavaScriptValueKindAndFlags.self)
+    #endif
+}

Sources/_CJavaScriptKit/include/_CJavaScriptKit.h

@@ -29,10 +29,15 @@ typedef enum __attribute__((enum_extensibility(closed))) {
   JavaScriptValueKindBigInt = 8,
 } JavaScriptValueKind;
 
+#if __Embedded
+// something about the bit field widths is not working with embedded
+typedef unsigned short JavaScriptValueKindAndFlags;
+#else
 typedef struct {
   JavaScriptValueKind kind: 31;
   bool isException: 1;
 } JavaScriptValueKindAndFlags;
+#endif
 
 typedef unsigned JavaScriptPayload1;
 typedef double JavaScriptPayload2;