Avoid unsafe when sizing types

go/unsafe.go → go/sizes.go

 package flatbuffers
 
-import "unsafe"
-
-var (
+const (
 	// See http://golang.org/ref/spec#Numeric_types
 
 	// SizeUint8 is the byte size of a uint8.
-	SizeUint8 = int(unsafe.Sizeof(uint8(0)))
+	SizeUint8 = 1
 	// SizeUint16 is the byte size of a uint16.
-	SizeUint16 = int(unsafe.Sizeof(uint16(0)))
+	SizeUint16 = 2
 	// SizeUint32 is the byte size of a uint32.
-	SizeUint32 = int(unsafe.Sizeof(uint32(0)))
+	SizeUint32 = 4
 	// SizeUint64 is the byte size of a uint64.
-	SizeUint64 = int(unsafe.Sizeof(uint64(0)))
+	SizeUint64 = 8
 
-	// SizeInt8  is the byte size of a int8.
-	SizeInt8 = int(unsafe.Sizeof(int8(0)))
+	// SizeInt8 is the byte size of a int8.
+	SizeInt8 = 1
 	// SizeInt16 is the byte size of a int16.
-	SizeInt16 = int(unsafe.Sizeof(int16(0)))
+	SizeInt16 = 2
 	// SizeInt32 is the byte size of a int32.
-	SizeInt32 = int(unsafe.Sizeof(int32(0)))
+	SizeInt32 = 4
 	// SizeInt64 is the byte size of a int64.
-	SizeInt64 = int(unsafe.Sizeof(int64(0)))
+	SizeInt64 = 8
 
 	// SizeFloat32 is the byte size of a float32.
-	SizeFloat32 = int(unsafe.Sizeof(float32(0)))
+	SizeFloat32 = 4
 	// SizeFloat64 is the byte size of a float64.
-	SizeFloat64 = int(unsafe.Sizeof(float64(0)))
+	SizeFloat64 = 8
 
 	// SizeByte is the byte size of a byte.
 	// The `byte` type is aliased (by Go definition) to uint8.
-	SizeByte = SizeUint8
+	SizeByte = 1
 
 	// SizeBool is the byte size of a bool.
 	// The `bool` type is aliased (by flatbuffers convention) to uint8.
-	SizeBool = SizeUint8
+	SizeBool = 1
 
 	// SizeSOffsetT is the byte size of an SOffsetT.
-	SizeSOffsetT = int(unsafe.Sizeof(SOffsetT(0)))
+	// The `SOffsetT` type is aliased (by flatbuffers convention) to int32.
+	SizeSOffsetT = 4
 	// SizeUOffsetT is the byte size of an UOffsetT.
-	SizeUOffsetT = int(unsafe.Sizeof(UOffsetT(0)))
+	// The `UOffsetT` type is aliased (by flatbuffers convention) to uint32.
+	SizeUOffsetT = 4
 	// SizeVOffsetT is the byte size of an VOffsetT.
-	SizeVOffsetT = int(unsafe.Sizeof(VOffsetT(0)))
+	// The `VOffsetT` type is aliased (by flatbuffers convention) to uint16.
+	SizeVOffsetT = 2
 )
 
 // byteSliceToString converts a []byte to string without a heap allocation.