Code Gen problem calling functions through pointers.

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Hi All,

Thanks for previous help with placing functions in data segment. The 
"__attribute__ (section..." solution works fantastic.

I am using ECGS 1.1.1 (binaries from Object Software web site) to cross 
compile from win95 to 68K (coff).

I have a problem with calling functions through pointers. I have assigned 
some unused vector table entries on 68K as holding places for functions 
that are called from applications link at a separate time. To call the 
functions (via the vector table entry) I use the following macros

#define TEST_FN_VECTOR	0x100
#define TestFunction() 	(*(void (*)(void))(TEST_FN_VECTOR<<2))()

I have found that the compiler sometimes generates the correct code. Eg.

        move.w #256,%a2
        jsr (%a2)

But at other times generates

        jsr 256.w

The second case will execute code at the vector address rather than using 
the contents of the vector as a pointer to the location to start executing 
from.

I have not been able to determine when or why the compiler decides to 
generate one form or the other. I did notice that the functions that had 
the erroneous code where generally simpler.

This seems like a code generation bug to me.

Is my cast from an integer to a function pointer OK?

If it is a bug has it been fixed in ECGS 1.1.2. ?

TIA
David Williams
DLC Software P/L
Email:davidwilliams@ozemail.com.au
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