Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Wed, 7 Mar 2012 11:02:30 -0600

Hi Dirk,

> On 3/7/12 2:50 AM, Dirk Zimoch wrote:
> > These two functions,
> > epicsSingleton<localHostName>::reference::~reference(void) and
> > epicsSingleton<localHostName>::reference::operator->(void) both
> > contain 'assert' (see src/libCom/cxxTemplates/epicsSingleton.h).
> >
> > 'assert' is a macro:
> > #   define assert(exp) ((exp) ? (void)0 : \
> >         epicsAssert(__FILE__, __LINE__, #exp, epicsAssertAuthor))
> >
> > Depending on the optimization level, '(void)0' may be eliminated
> > and the code becomes shorter (by 4 bytes = 1 PPC instruction).
> >
> > Try to 'make clean' in the epics base top directory and compile
> > again.

The problem is more subtle than that, although I suspect that different 
optimization levels is probably the underlying cause.

Remember Lewis is using a very old version of g++, from back when C++ 
templates were new; my guess is that ldppc is recompiling the template 
instances it needs to link the code behind the scenes, but it wasn't told the 
optimization level that g++ppc used to compile the instances that appear in 
the .o files it's linking with so it doesn't get the same length code and 
generates that warning.  There may be a flag we could turn on to show more 
about what's going on inside ldppc, but it's really not worth looking into 
IMHO; better to spend the time upgrading to vxWorks 5.5.

- Andrew
-- 
Never interrupt your enemy when he is making a mistake.
-- Napoleon Bonaparte

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System