I have an array of function pointers that I'd like to ensure stays in program memory, rather than consume RAM.  However, when I add the "const" keyword, I get a compiler error.  Here is the code as it exists without the compiler error:

PmReturn_t (* usr_nat_fxn_table[])(pPmFrame_t *) =
{
    nat_placeholder_func,
    nat_01_mbed___init__,
    nat_02_mbed_read_u16,
    /* ... many more funcs ... */
};

PmReturn_t (* const usr_nat_fxn_table[])(pPmFrame_t *) =
{
    nat_placeholder_func,
    nat_01_mbed___init__,
    nat_02_mbed_read_u16,
    /* ... many more funcs ... */
};

The place to insert const is at src/platform/mbed/main_nat.c:1569

The table is used in src/vm/interp.c:32 and 2032

Does my C-like understanding of const not apply to a C++ compiler?

I found a nice explanation here. I added the following to pm.h:

typedef PmReturn_t (* NATFNPTR) (pPmFrame_t *);
extern NATFNPTR const std_nat_fxn_table[];
extern NATFNPTR const usr_nat_fxn_table[];

NATFNPTR const usr_nat_fxn_table[] =

NATFNPTR const std_nat_fxn_table[] =

NB: in your pm.h you have wrong nesting of #ifdefs for __PM_H__ and __cplusplus.

In contrast, the following program with a simple array of function pointers with a const declaration compiles and works just fine: http://mbed.org/users/dwhall/programs/ArrayOfFxnPtrs/latest

GCC handles the "PmReturn_t (* const usr_nat_fxn_table[])(pPmFrame_t *) =" declaration just fine.  But I imagine using a typedef will be more compatible across different compilers.  Thank you Igor.

(I posted my other reply before I refreshed and saw your reply)

!!Dean

Your example works in one file but not if you define table in one and use it in another.

Actually, I take that back. I was able to make it link by declaring the definition of the table "extern". I guess mbed compiler used default hidden visibility, so you need to explicitly mark stuff you want exported as such.