20.4. Architectures

This section describes characteristics of architectures that affect all uses of gdb with the architecture, both native and cross.

20.4.1. A29K

set rstack_high_address address

On AMD 29000 family processors, registers are saved in a separate register stack. There is no way for gdb to determine the extent of this stack. Normally, gdb just assumes that the stack is "large enough". This may result in gdb referencing memory locations that do not exist. If necessary, you can get around this problem by specifying the ending address of the register stack with the set rstack_high_address command. The argument should be an address, which you probably want to precede with 0x to specify in hexadecimal.

show rstack_high_address

Display the current limit of the register stack, on AMD 29000 family processors.

20.4.2. Alpha

See the following section.

20.4.3. MIPS

Alpha- and MIPS-based computers use an unusual stack frame, which sometimes requires gdb to search backward in the object code to find the beginning of a function.

To improve response time (especially for embedded applications, where gdb may be restricted to a slow serial line for this search) you may want to limit the size of this search, using one of these commands:

set heuristic-fence-post limit

Restrict gdb to examining at most limit bytes in its search for the beginning of a function. A value of 0 (the default) means there is no limit. However, except for 0, the larger the limit the more bytes heuristic-fence-post must search and therefore the longer it takes to run.

show heuristic-fence-post

Display the current limit.

These commands are available only when gdb is configured for debugging programs on Alpha or MIPS processors.