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To: Tom Tromey Cc: K via Gdb Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.30 X-BeenThere: gdb@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Gdb mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: K via Gdb Reply-To: K Errors-To: gdb-bounces~public-inbox=simark.ca@sourceware.org Sender: "Gdb" > > Could you say more about what exactly you're doing? > > Like are you writing an unwinder in gdb? Or writing one in Python? > > I'm implementing an unwinder via the GDB-JIT C API for JIT code where generating custom ELF debug information is too onerous. The first article I read on it, by the implementor Sanjoy D(?) mentioned your name as originating the approach! So I'm just providing the functions called for by the struct in the API - unwind and get-frame-id (plus the function name/line number info separately). So gdb has no ELF info to look at (other than of the binary that is generating the JIT code), so I was expecting gdb to immediately defer to the jit-reader.so loaded into itself with the defined unwind function which has a few printf statements so I know when it runs ... and it isn't being called until 2 lines of backtrace have already been emitted, and only then on garbage data because it has already gone awry interpreting the stack contents/frame (with those first 2 lines above).