Experimental Physics and
Industrial Control System

Michael Davidsaver via Tech-talk <tech-talk at aps.anl.gov> · Mon, 15 May 2023 11:16:23 -0700

On 5/15/23 10:37, David A. Slimmer via Tech-talk wrote:

I’m trying to implement device support under base-7.0.5, and I’m getting the following warning when I compile:

Biascontroller_registerRecordDeviceDriver.cpp:382:62: warning: missing initializer for member 'iocshFuncDef::usage' [-Wmissing-field-initializers]

   382 |     {"Biascontroller_registerRecordDeviceDriver", 1, rrddArgs};

       |

I looked at the Biascontroller_registerRecordDeviceDriver.cpp code, but it looks identical to the code generated for another project using device support built with an earlier version of EPICS base (R3.15 I think).

Any ideas where I might look to track this down?

Firstly, this warning can simply be ignored.  The "uninitialized" field will
be initialized to NULL in this context, which is the intent.

The warning comes from the addition of usage messages for IOC shell commands
in 7.0.4.

https://github.com/epics-base/epics-base/commit/ce4fb6085ffccd2ad0c29191d221c55341a485a6

There is no particular reason why the generated *_registerRecordDeviceDriver
commands don't have a usage message.  Although I can't immediately think of
what the wording would be.

As a note for _external_ modules wishing to provide a usage message, the macro
IOCSHFUNCDEF_HAS_USAGE can be tested to determine if iocshFuncDef::usage exists.

https://github.com/epics-base/epics-base/blob/cb97d662a74b8de6d7265a0863edbf88d0486f28/modules/database/src/template/top/exampleApp/src/_APPNAME_Hello.c#L20-L30

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System