How Can I Debug A preload.so for 3rd Party With VSCode?

[zxcvbnm3057]

I am tring to debug a .so which will be load by a 3rd party program, which I do NOT have source code and of cource wasn't compile with gcc -g. Maybe I should use attaching mode, but I dont know how to attach a preload dynamic library of a 3rd program. So I was trying the launch mode. However, I cant get into any of my breakpoint. Here is some code and setting from my program. Please tell me where did i miss.

launch.json

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "(gdb) Attach",
            "type": "cppdbg",
            "request": "attach",
            "program": "${workspaceFolder}/build/libpreload.so",
            "MIMode": "gdb"
        },
        {
            "name": "(gdb) Launch",
            "type": "cppdbg",
            "request": "launch",
            "program": "THE_3RD_PARTY_EXECUTABLE_PATH",
            "args": [],
            "stopAtEntry": true,
            "cwd": "${workspaceFolder}",
            "environment": [
                {
                    "name": "LD_PRELOAD",
                    "value": "build/libpreload.so"
                }
            ],
            "externalConsole": false,
            "MIMode": "gdb",
        }
    ]
}

and this hack function in my source code:

class Bridge
{
public:
	Bridge()
	{
		printf("initialized! successfully!\n");
                // breakpoint and other code
	}

} theBridge;

The string print normally but breakpoint was never hit.

I keep getting this warnning when I try to use gdb manually

warning: Error disabling address space randomization: Operation not permitted

Any help?