How to get the relative address of a field in a structure dump. [C]

Question

We\'re working on a C program compiled with arm-eabi-gcc under Linux.

We\'re using a dump of a large structure and we\'re having problems determining at which adress we

Answer 1

For anyone reading this years later, maybe following a search engine result: Since gdb 8.1, its builtin ptype command has the /o flag for this.
It will print offset and size of MyType's members and also "holes" (padding), like:

(gdb) ptype /o MyType
/* offset    |  size */  type = class MyType {
/*  0        |     4 */    int foo;
/* XXX  4-byte hole  */
/*  8        |     8 */    void* ptr;
                           /* total size (bytes):  16 */
                         }