How does endianness affect what you see in GDB memory dumps?

x86 is little-endian — the least significant byte sits at the lowest address — but x/ with a word/giant size reassembles the value for you; only raw x/xb byte dumps show the reversed order.

* Little-endian: LSB at lowest address; x/xw reassembles, x/xb shows raw bytes. *

Example: The integer 0x04030201 in memory:

Address: 0x00  0x01  0x02  0x03
Content: 0x01  0x02  0x03  0x04  (LSB first)

GDB handles it for you:

# Shows "correctly" as 0x04030201
(gdb) x/xw 0x7fffffffe000
0x04030201

# Shows raw bytes (reversed from how you'd write the number)
(gdb) x/4xb 0x7fffffffe000
0x01  0x02  0x03  0x04

When it matters:

• Examining strings: No effect (strings are byte sequences, order preserved)
• Examining integers: x/xw shows the "correct" value; x/xb shows raw byte order
• Examining addresses: Use x/a or x/xg — GDB handles endianness

Forensic trap: If you dump memory as raw bytes and try to read addresses manually, remember to reverse each group of 8 bytes.

Go deeper:

• Endianness - little-endian stores the least-significant byte at the smallest address (x86, ARM, RISC-V)