-isystem || Trickify TrickHLA

[simnaut]

Hello,
In a similar vein to #177, I'm looking in to using the -isystem feature to treat TrickHLA and the RTI libs as a third-party libraries in our sim. I think this will let us build with -Werror without erroring on any TrickHLA or RTI warnings. The c++ HLAe headers use of auto_ptr will inevitably cause us to error in particular with -Werror on.

I was curious what y'all think about me adding in to https://github.com/nasa/TrickHLA/blob/master/makefiles/S_hla.mk a check for existence of a "include as system header" variable to swap the -I to -isystem?

[simnaut]

Actually, I'm learning -isystem is expecting TrickHLA to be precompiled. I'm thinking that perhaps if TrickHLA was a Trickified Project Library this would accomplish what we're hoping for. Do y'all know if TrickHLA has been trickified or is trickifiable?

[dandexter]

TLDR; look at option 3 listed below for the recommended approach.

We have briefly discussed making TrickHLA a Trickified project library to possibly reduce the roughly 40 minutes it takes now to compile all the example simulations. However, it is low on the priority list for now.

The IEEE 1516-2010 (i.e. HLA Evolved) standard uses auto_ptr and declared exceptions which have since been deprecated and in some cases removed in the newer c++ standards. Newer compilers will generate a large volume of warnings about the deprecated APIs. I have added pragma code to TrickHLA source files to turn off the deprecated API warnings in specific code sections. I wrap the pragma around the inclusion of the RTI header files and sometime around the entire source code as needed. For example, pragma wrapped around RTI include files:

// C++11 deprecated dynamic exception specifications for a
// function so we need to silence the warnings coming from
// the IEEE 1516 declared functions.
// This should work for both GCC and Clang.
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated"
// HLA include files.
#include "RTI/RTI1516.h"
#pragma GCC diagnostic pop

Just a heads up that sometimes swig can autogenerate code that can result in compile time warnings for your simulation. You may or may not be able to find and change the model code to make them go away since the warnings tend to obscure the root cause.

Here are some options:

1. TrickHLA supports HLA 4, which no longer uses auto-pointers and declared exceptions. Plus there is no restriction on the use of the newer C++ standards. You could use HLA 4 for internal development and run with HLA Evolved when running with other groups. Not really recommended unless you plan on going to HLA 4.

2. Use pragma example provided to wrap around RTI headers and code that uses auto-pointers or declared exceptions. TrickHLA already does this to silence the deprecated warnings in the HLA APIs. You could use the same technique. Recommend for helping resolve deprecation warnings in your code.

3. Recommended approach of instead of globally setting -Werror in the TRICK_CXXFLAGS for the entire simulation is to just apply it to only the code you want. Add a "makefile_overrides" file to every source directory you would like to treat compile warnings as errors with the makefile_overrides file containing the following:

#===============================================================
# File: makefile_overrides
# Treat warnings as errors.
#===============================================================
objects: TRICK_CFLAGS   += -Werror
objects: TRICK_CXXFLAGS += -Werror

[simnaut]

Hi Dan, thanks for taking the time to provide some options. I didn't know about option 3 so thanks for sharing.
I am fine with closing this, or, also fine keeping it open until trickification.