Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Sat, 25 Jun 2011 23:27:19 -0500

Hi Ben,

On Saturday, June 25, 2011 20:00:34 Benjamin Franksen wrote:
> 
> This is correct; the problem is that the perl script thinks the test should
> succeed, not fail, since the EPICS_HOST_ARCH does not match against the
> string '64'. So, I rather have to adapt the expectation and refine the
> heuristic that tries to determine 64-bit-ness of the host arch. What is
> the value of EPICS_HOST_ARCH for your system?

You're going to have "fun" with this test on Macs, which can be configured to 
actually execute the C compiler up to 4 times when you run gcc once, depending 
on the setting for ARCH_CLASS which sends a -arch option to gcc.  This is how 
you get it to generate Fat Binaries, which contain code for more than one 
processor architecture.  The EPICS build system configuration lets individual 
sites decide what architectures they want to include in their binaries on 
darwin.

If you look at the comments in the file
    base/configure/os/CONFIG_SITE.Common.darwin-ppcx86
you'll get some idea of the possible combinations (the CONFIG_SITE files for 
the other darwin target-architectures contain a reduced list of possibilities, 
but in practice any target-arch can be configured to build for any combination 
of binaries).  This means you shouldn't try to rely on EPICS_HOST_ARCH 
containing the string "64" when you're building for a 64-bit CPU, and even if 
it does it isn't necessarily going to be /only/ building for a 64-bit CPU.

I think trying to parse the output from the compiler is not worth doing, it's 
too variable given the wide variety of architectures EPICS can be built for.

- Andrew

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System