Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Mon, 30 Apr 2012 17:01:58 -0500

Hi,

On 2012-04-30 Ru Igarashi wrote:
> I was compiling the synApps areaDetector on Cygwin 1.7 under
> base 3.14.12.2 using the system libs for netCDF and HDF5 for
> fun, but ran into a linker error, complaining that the symbol
> "_function" was multiply defined, once in registryIoc.lib and
> once in libnetcdf.a.  I tracked the EPICS symbol down to the
> "const char *function" variable in BASE/src/registry/registryFunction.c:
> 
> const char *function = "function";
> static void *registryID = (void *)&function;
> 
> Seeing as neither symbols seem to be used outside of that file,
> I prepended "static" to the declaration of "*function", recompiled
> EPICS, and recompiled areaDetector successfully.  I've only tested
> the new base with softIoc, and areaDetector not at all, so by no
> means have I adequately tested this hack.  I cannot find any
> mention of this particular hack in TechTalk or base Release Notes
> or base Known Problems.
> 
> Instead, I thought I should ask, is this hack safe (or otherwise
> appropriate)?

That symbol should not be globally visible, so your change is perfectly safe 
and correct; thanks for pointing it out!  I will fix this for the next 
release.

- 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