gdb prints wrong values when modifying arguments

Question

System

Fresh install of codeblocks 12.11 + mingw pack.

• win7 64
• gcc 4.7.1
• gdb 7.5

Example code

Compiled wit

Answer 1

gcc does not generate debugging info correctly for values that are in registers -- either values that have been put in registers or values that start there due to the calling conventions. This is a long-standing problem with gcc since at least 4.0, and makes it tricky to debug things.