all: use unsafe.SliceData where appropriate

src/runtime/runtime_tinygowasm.go

@@ -39,7 +39,7 @@ var (
 	putcharBuffer        = [putcharBufferSize]byte{}
 	putcharPosition uint = 0
 	putcharIOVec         = __wasi_iovec_t{
-		buf: unsafe.Pointer(&putcharBuffer[0]),
+		buf: unsafe.Pointer(unsafe.SliceData(putcharBuffer[:])),
 	}
 	putcharNWritten uint
 )

src/runtime/runtime_wasip1.go

@@ -35,7 +35,7 @@ func os_runtime_args() []string {
 		// Obtain the command line arguments
 		argsSlice := make([]unsafe.Pointer, argc)
 		buf := make([]byte, argv_buf_size)
-		args_get(&argsSlice[0], unsafe.Pointer(&buf[0]))
+		args_get(&argsSlice[0], unsafe.Pointer(unsafe.SliceData(buf)))
 
 		// Convert the array of C strings to an array of Go strings.
 		args = make([]string, argc)

src/runtime/string.go

@@ -280,7 +280,7 @@ func cgo_GoBytes(ptr unsafe.Pointer, length uintptr) []byte {
 	// of upstream Go.
 	buf := make([]byte, length)
 	if length != 0 {
-		memcpy(unsafe.Pointer(&buf[0]), ptr, uintptr(length))
+		memcpy(unsafe.Pointer(unsafe.SliceData(buf)), ptr, uintptr(length))
 	}
 	return buf
 }