How to disable C4_DEBUG_BREAK

[captain-yoshi]

I have a cmake project which includes the rapidyaml library. When building my library in Debug mode, ryml also switches to Debug and thus triggers C4_DEBUG_BREAK in the code, especially in the _RYML_CB_ERR. I have a custom try catch mechanism, which will trigger and then resume. This makes it hard when debugging my library because it triggers a lot of false positive signal traps.

Is there a way to not switch rapidyaml to a Debug build when building my library in Debug? Or a way to disable C4_DEBUG_BREAK.

[biojppm]

It can be disabled both runtime and compile-time.

For runtime, here's the relevant line:

#   define C4_ERROR(msg, ...)                               \
    do {                                                    \
        if(c4::get_error_flags() & c4::ON_ERROR_DEBUGBREAK) \
        {                                                   \
            C4_DEBUG_BREAK()                                \
        }                                                   \
        c4::handle_error(C4_SRCLOC(), msg, ## __VA_ARGS__); \
    } while(0)

So all you need to do is to use this somewhere in your code:

ryml::set_error_flags(ryml::get_error_flags() & ~ryml::ON_ERROR_DEBUGBREAK);

For compile time, use the NDEBUG macro. Here's the relevant line:

#ifdef NDEBUG
#   define C4_DEBUG_BREAK()
#else
//... enable C4_DEBUG_BREAK
#endif

I recognize the NDEBUG way may be a bit heavy-handed. Maybe adding an auxiliary C4_NO_DEBUG_BREAK macro would be a better approach than the current one:

#if defined(NDEBUG) || defined(C4_NO_DEBUG_BREAK)
#   define C4_DEBUG_BREAK()
#else
//... enable C4_DEBUG_BREAK
#endif

[biojppm]

Actually, I just noticed the C4_DEBUG_BREAK() call in _RYML_CB_ERR() is not honoring the error flags. Sorry for that.

I will work on a PR to address both this problem and to add the C4_NO_DEBUG_BREAK disabler.

[captain-yoshi]

@biojppm Tried to set C4CORE_NO_DEBUG_BREAK at compile time in my project with 59ea113 like so :

cmake_minimum_required(VERSION 3.1.3)
project(moveit_serialization)

...
# also tried with option
# option(C4_NO_DEBUG_BREAK "disable use of debug break even in debug builds" ON)
SET(C4_NO_DEBUG_BREAK ON CACHE BOOL "disable use of debug break even in debug builds")
add_subdirectory(ext/ryml ryml)

Followed this option from stackoverflow.

When building in Debug mode, GDB still receives a trap signal :

Thread 1 "plot_dataset" received signal SIGTRAP, Trace/breakpoint trap.
trap_instruction () at /home/captain-yoshi/ws/ros/mimic_ws/src/moveit_serialization/ext/ryml/ext/c4core/src/c4/ext/debugbreak/debugbreak.h:48
48	}
(gdb) bt
#0  trap_instruction () at /home/captain-yoshi/ws/ros/mimic_ws/src/moveit_serialization/ext/ryml/ext/c4core/src/c4/ext/debugbreak/debugbreak.h:48
#1  0x00007ffff7dd7a84 in debug_break () at /home/captain-yoshi/ws/ros/mimic_ws/src/moveit_serialization/ext/ryml/ext/c4core/src/c4/ext/debugbreak/debugbreak.h:143
#2  c4::yml::detail::RoNodeMethods<c4::yml::ConstNodeRef, c4::yml::ConstNodeRef>::operator>><bool> (this=0x7fffffffb000, v=@0x7fffffffaf18: false)
    at /home/captain-yoshi/ws/ros/mimic_ws/src/moveit_serialization/ext/ryml/src/c4/yml/node.hpp:366
#3  0x00007ffff79d5aed in computePredicate(c4::yml::ConstNodeRef const&, c4::yml::ConstNodeRef const&, moveit_benchmark_suite::Predicate) ()
   from /home/captain-yoshi/ws/ros/mimic_ws/devel/lib/libmoveit_benchmark_suite_core.so
#4  0x00007ffff79d790d in moveit_benchmark_suite::DatasetFilter::filterMetadata(c4::yml::ConstNodeRef const&, moveit_benchmark_suite::Token const&, moveit_benchmark_suite::Predicate) ()
   from /home/captain-yoshi/ws/ros/mimic_ws/devel/lib/libmoveit_benchmark_suite_core.so
#5  0x00007ffff79d88ba in moveit_benchmark_suite::DatasetFilter::filter[abi:cxx11](unsigned long, c4::yml::Tree&, std::vector<moveit_benchmark_suite::Filter, std::allocator<moveit_benchmark_suite::Filter> > const&) () from /home/captain-yoshi/ws/ros/mimic_ws/devel/lib/libmoveit_benchmark_suite_core.so
#6  0x00007ffff7e25ff0 in moveit_benchmark_suite::tools::GNUPlotDataset::plot (this=0x7fffffffb9a0, layout=..., id=0)
    at /home/captain-yoshi/ws/ros/mimic_ws/src/moveit_benchmark_suite/tools/src/gnuplot.cpp:870
#7  0x00007ffff7e25e06 in moveit_benchmark_suite::tools::GNUPlotDataset::plot (this=0x7fffffffb9a0, dataset_files=std::vector of length 1, capacity 1 = {...})
    at /home/captain-yoshi/ws/ros/mimic_ws/src/moveit_benchmark_suite/tools/src/gnuplot.cpp:843
#8  0x0000555555567d51 in main (argc=1, argv=0x7fffffffbba8) at /home/captain-yoshi/ws/ros/mimic_ws/src/moveit_benchmark_suite/tools/src/plot_dataset.cpp:35

Not sure if it's me or something missing in the callback error trigger.

[biojppm]

The define is C4_NO_DEBUG_BREAK but the cmake option is C4CORE_NO_DEBUG_BREAK.

[captain-yoshi]

That's what I initially tested, but gives the same backtrace.

I think there may be missing a branch point here depending on the macro ?

[biojppm]

At the moment it's hard for me to investigate. Can you look into what's happening with the defines? Adding a judicious #error here or there will immediately reveal the source of the problem.

But make sure to use the current master tip. I think when the issue was closed something was still missing.

[captain-yoshi]

It's working now.

We use Catkin a meta-buildsystem to build cmake projects. There is a problem with the override, but the fault is not on ryml side.

[captain-yoshi]

Working when changing directly from the c4core CMakeLists. Not working from my project.

I will investigate why it does not propagate from my top level project.

[captain-yoshi]

Disabling at runtime works perfectly! Disabling at compile time seems to not work, but my project may be to blame. Il leave this as is.

[biojppm]

How are you setting up your project to use the compile-time macro?