C compilation flags: +DD64 vs +DA2.0W

[scoolj]

One of the HP documentation page tells as below...

+DD64 must be used to generate 64-bit code for HP-UX on IA64.

+DA2.0W must be used to generate 64-bit code for HP-UX on PA-RISC.

But I could use both the flags on HP UX PA2.0/ B.11.23/64 Bit platform to get the desired binary.

Can someone pls highlight the purpose & difference between these two flags, and the impacts of cross usage.

Br,
Srini

[James R. Ferguson]

Hi Srini:

The '+DD64' is the new form as you would suspect, and works on PA-RISC or Itanium for *both* C and C++. This is the preferred form.

The older '+DA2.0W' was the first 64-bit (W=wide) PA-RISc 2.0 implementation. Its 32-bit corollary is '+DA2.0N' (N=narrow).

Regards!

...JRF...

[scoolj]

Thanks James.

Is the flag +DD64 can be used on all HP-UX platforms ? regardless of architectures e.g: PA Risc 1.x/PA Risc 2.x/Itanium etc..

[Dennis Handly]

The correct option is +DD64. It works on both PA and IPF.
+DA2.0W is an obsolete PA only form.

>regardless of architectures e.g: PA RISC 1.x

While you may be able to compile with +DD64 on an old PA1.1 box, you can't run it there.

>JRF: Its 32-bit corollary is +DA2.0N

Or just +DA2.0.