<jdk-dev>/jdk/src/jdk.jdwp.agent/share/native/libdt_socket/socketTransport.c: In function ‘mask_s2u’:
<jdk-dev>/jdk/src/jdk.jdwp.agent/share/native/libdt_socket/socketTransport.c:389:22: warning: left shift of negative value [-Wshift-negative-value]
     *mask = htonl(-1 << (32 - m));
                      ^
Suggested fix:

diff --git a/src/jdk.jdwp.agent/share/native/libdt_socket/socketTransport.c b/src/jdk.jdwp.agent/share/native/libdt_socket/socketTransport.c
--- a/src/jdk.jdwp.agent/share/native/libdt_socket/socketTransport.c
+++ b/src/jdk.jdwp.agent/share/native/libdt_socket/socketTransport.c
@@ -386,7 +386,7 @@
        return instr;
     }
 
- *mask = htonl(-1 << (32 - m));
+ *mask = htonl((uint32_t)(~0) << (32 - m));
     return s;
 }