Debugger hangs when a breakpoint is hit in the presence of a frame-filter

[TSonono]

Environment

• OS and version: Windows 11 Enterprise 23H2
• VS Code: 1.97.2
• C/C++ extension: v1.23.6
• OS and version of remote machine (if applicable): SUSE Linux Enterprise Server 15-SP4
• GDB / LLDB version: GDB 14.1

Bug Summary and Steps to Reproduce

Bug Summary: The debugger hangs when a breakpoint is hit in the presence of a GDB frame-filter. This happens even if the frame filter is returning an untouched frame iterator. No such issues occur when running GDB directly from CLI.

Steps to reproduce:

1. Place a breakpoint that will be hit during program execution.
2. Run a program.
3. Attach to it using the provided debugger configuration (I assume this bug is also applicable for launch requests)
4. Have the program hit a breakpoint
5. Observe that the debugger hangs when a breakpoint is hit.

I'm submitting this issue since I think it would be really nice to be able to use the cppdbg debugger while having a frame filter applied.

Debugger Configurations

launch.json:


{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "(gdb) Attach",
            "type": "cppdbg",
            "request": "attach",
            "program": "a.out",
            "MIMode": "gdb",
            "setupCommands": [
                {
                    "description": "Enable pretty-printing for gdb",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                },
                {
                    "description": "Set Disassembly Flavor to Intel",
                    "text": "-gdb-set disassembly-flavor intel",
                    "ignoreFailures": true
                },
                {
                    "description": "Source frame-filter",
                    "text": "source <path-to-frame-filter-py>"
                    "ignoreFailures": true
                },
                {
                    "description": "Enable frame filters",
                    "text": "-enable-frame-filters",
                    "ignoreFailures": true
                }
            ],
            logging: {
                "engineLogging": true,
                "trace": true,
                "traceResponse": true
            }
        }
    ]
}

Debugger Logs

--> E (output): {"type":"event","event":"output","body":{"category":"console","output":"1: (8566) ->(gdb)\n"},"seq":1302}
1: (8566) ->(gdb)
--> E (output): {"type":"event","event":"output","body":{"category":"console","output":"1: (8567) 1035: elapsed time 26\n"},"seq":1304}
1: (8567) 1035: elapsed time 26
--> E (output): {"type":"event","event":"output","body":{"category":"console","output":"1: (8573) Send Event AD7BreakpointEvent\n"},"seq":1306}
1: (8573) Send Event AD7BreakpointEvent
--> E (output): {"type":"event","event":"output","body":{"category":"console","output":"Execute debugger commands using \"-exec <command>\", for example \"-exec info registers\" will list registers in use (when GDB is the debugger)\n"},"seq":1308}
Execute debugger commands using "-exec <command>", for example "-exec info registers" will list registers in use (when GDB is the debugger)
--> E (stopped): {"type":"event","event":"stopped","body":{"reason":"breakpoint","threadId":135549,"allThreadsStopped":true,"source":{"name":"extended-capabilities.dml","path":"/disk2/tsonono/repos/simics-base/src/devices/dml-lib/pcie/extended-capabilities.dml","sources":[],"checksums":[]},"line":246,"column":1},"seq":1310}
<--   C (threads-15): {"command":"threads","type":"request","seq":15}
--> R (threads-15): {"type":"response","request_seq":15,"success":true,"command":"threads","body":{"threads":[{"id":135549,"name":"mini-python [135549]"},{"id":135566,"name":"mini-python [135566]"},{"id":135568,"name":"mini-python [135568]"},{"id":135570,"name":"mini-python [135570]"},{"id":135571,"name":"mini-python [135571]"},{"id":135580,"name":"mini-python [135580]"},{"id":136031,"name":"simics-poll [136031]"}]},"seq":1313}
<--   C (stackTrace-16): {"command":"stackTrace","arguments":{"threadId":135549,"startFrame":0,"levels":20},"type":"request","seq":16}
--> E (output): {"type":"event","event":"output","body":{"category":"console","output":"1: (8749) <-1036-list-features\n"},"seq":1316}
1: (8749) <-1036-list-features
--> E (output): {"type":"event","event":"output","body":{"category":"console","output":"1: (8749) ->1036^done,features=[\"frozen-varobjs\",\"pending-breakpoints\",\"thread-info\",\"data-read-memory-bytes\",\"breakpoint-notifications\",\"ada-task-info\",\"language-option\",\"info-gdb-mi-command\",\"undefined-command-error-code\",\"exec-run-start-option\",\"data-disassemble-a-option\",\"simple-values-ref-types\",\"python\"]\n"},"seq":1318}
1: (8749) ->1036^done,features=["frozen-varobjs","pending-breakpoints","thread-info","data-read-memory-bytes","breakpoint-notifications","ada-task-info","language-option","info-gdb-mi-command","undefined-command-error-code","exec-run-start-option","data-disassemble-a-option","simple-values-ref-types","python"]
--> E (output): {"type":"event","event":"output","body":{"category":"console","output":"1: (8749) ->(gdb)\n"},"seq":1320}
1: (8749) ->(gdb)
--> E (output): {"type":"event","event":"output","body":{"category":"console","output":"1: (8751) 1036: elapsed time 2\n"},"seq":1322}
1: (8751) 1036: elapsed time 2
--> E (output): {"type":"event","event":"output","body":{"category":"console","output":"1: (8753) <-1037-stack-list-arguments --thread 1 2 0 84\n"},"seq":1324}
1: (8753) <-1037-stack-list-arguments --thread 1 2 0 84

Additional information

It's always the -stack-list-arguments that is the last command in the trace.

My frame_filter.py file:

import gdb

class FrameFilter():

    def __init__(self):
        # Frame filter attribute creation.
        #
        # 'name' is the name of the filter that GDB will display.
        #
        # 'priority' is the priority of the filter relative to other
        # filters.
        #
        # 'enabled' is a boolean that indicates whether this filter is
        # enabled and should be executed.

        self.name = "Foo"
        self.priority = 100
        self.enabled = True

        # Register this frame filter with the global frame_filters
        # dictionary.
        gdb.frame_filters[self.name] = self

    def filter(self, frame_iter):
        return frame_iter

FrameFilter()

[github-actions]

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