Darwin: fix warning in darwin_error_str()

os/darwin_usb.c:63: warning: return discards qualifiers from pointer
target type

diff --git a/libusb/os/darwin_usb.c b/libusb/os/darwin_usb.c
index 88c4962..dfae564 100644 (file)
--- a/libusb/os/darwin_usb.c
+++ b/libusb/os/darwin_usb.c
@@ -57,7 +57,7 @@ static void darwin_isoc_callback (struct usbi_transfer *itransfer, kern_return_t
 static void darwin_control_callback (struct usbi_transfer *itransfer, kern_return_t result, UInt32 io_size);
 static void darwin_async_io_callback (void *refcon, IOReturn result, void *arg0);
 
-static char *darwin_error_str (int result) {
+static const char *darwin_error_str (int result) {
   switch (result) {
   case kIOReturnSuccess:
     return "no error";