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Unexpected Memory Value Fluctuations in GDB While Debugging Pointer in x86-64 C Program

In my last question, I misunderstood how GDB interprets memory when using different formats like `x/d` and `x/1wd`. After some digging, I realized the issue was related to GDB displaying the same memory contents as both signed and unsigned integers. That cleared up the confusion about the “flipping” values.

Funny how I am facing a different issue with pointer manipulation and register inspection. I’m debugging a simple `C` program where `$rbx` is pointing to dynamically allocated memory. Here’s the setup in my main.c file
When I inspect `$rbx` in GDB, I expect it to point to the buffer and show the correct values as `28` and `-5604` for `ptr[0]` and `ptr[1]`. When I execute these commands, I get some strange behavior which I logged in bash.txt
. Been making use of `x86-64`, `GDB version 10.1`
and `Ubuntu 20.04`as my environment
.
The values at the memory location are flipping between 28 and -5604, even though the program hasn’t modified the memory or stepped through any new instructions. I’m not sure if this is like caching, memory alignment issues, or a problem with the heap?

  1. heidi.tech#0

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