Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Fri, 12 Jul 2002 17:05:34 -0500

Brian McAllister wrote:
> 
> >>> On 7/12/2002 at 16:40:49 CDT, Andrew Johnson wrote:
> 
>   > EPICS 3.14 needs a fairly modern C++ compiler to compile - 2.7.2 is way
>   > too old.  You *will* have to use a version of gcc built from the
>   > official WRS sources, and Tornado 2.x when you want to upgrade to that
>   > (which is exactly where Ernest Williams and David Thompson came in with
>   > this problem).
> 
> The version from WRS is still "2.7.2".
>
> Has WRS really hacked better C++ support into it, instead of migrating to
> the newer gcc ?

No, the WRS version is a combination of a gcc-2.7.2 C compiler back end
(modified by cygnus, probably with various bug fixes added), and later
versions of the G++ back end.  In Tornado 2.0 the C++ compiler was based
on EGCS 1.0.2, in the new Tornado 2.1 and 2.2 releases I believe it's
based on the Red-Hat gcc-2.96, or maybe something newer (not sure about
the Tornado 2.2 C compiler back-end).

I think WRS pay Red Hat to produce compiler versions to their
specification.  The problems Ernest and Dave wrestled with when they tried
to build a C++ cross-compiler from GNU sources were associated with name
mangling changes, and the fact that exception support is different for
each of these g++ versions.

- Andrew
-- 
Larry McVoy: "Learn how to think in C++ but don't ever program in it."

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System