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javajava-native-interfacegdb

gdb hanging when attaching to java process

I'm trying to debug a JNI code. For this purpose I'm following an idea about attaching gdb to the java process running my Java code. The problem is when I do that gdb hangs at pthread_join() inside libjli.so, producing the following output.

0x7fff59850000
0x00007ffa9fbb8218 in pthread_join ()
   from /lib/x86_64-linux-gnu/libpthread.so.0

And then I can't make my Java code attend to requests (it is a server).

Update: It is not inside pthread_join(), but after that, when I continue the execution and make a request to the server. It is using actually libzmq.so for communication. I don't know if gdb interferes the library somehow.

Solution

  • Finally found out what was going on. Java uses SIGSEGV during garbage collection, which is intercepted by gdb causing an apparently crash. To solve this I added handle SIGSEGV pass nostop to my ~/.gdbinit file.