Fix software breakpoint handling issues #76
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This was referenced Jan 5, 2026
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This PR addresses some software breakpoint bugs that can cause crashes or unexpected behaviours in multi-threaded debugging.
Firstly, when multiple threads hit a breakpoint simultaneously the debug events are queued. If a user deletes the breakpoint while events are still pending, the queued events arrive with no breakpoint in the map. This before gave
DBG_EXCEPTION_NOT_HANDLEDwhich caused it to fall through and cause unexpected issue. This now detects this scenario and handles it gracefully.Secondly,
MemWriteUnsafecalls during the breakpoint handling never checked return values, now I check it and handle the failured appropriately.Finally, this PR implements
MemWriteSafe(previously just the same asMemWriteUnsafe) so now writing to a breakpoint address will no longer destroy the breakpoint.Should close x64dbg/x64dbg#3654