inequation / cppbuild Goto Github PK

This was the root cause of #11 and is "fixed" as of now by printing an error message. However, as of now, cppbuild will still attempt to execute the build graph. It should stop instead as early as possible (or as configured).

Too many times I pass these things around as params.

Also take the opportunity to verify whether the graph execution tasks really need to keep a copy of the context, perhaps a reference would be sufficient?

Calling override_options(string_vector{ "-j2" }); from describe() has no effect. I'm not sure it really needs to; doing so will require restarting the task scheduler. Leaving this here just for tracking.

For details: https://randomascii.wordpress.com/2018/12/03/a-not-called-function-can-cause-a-5x-slowdown/

Even if (or especially if?) those have their own, separate build.cpp files.

Mock-up:

namespace library
{
    #include "../src/library/build.cpp"
};

std::pair<std::string, std::string> describe(target_map& targets, configuration_map& configs, toolchain_map& toolchains)
{
    add_dependency(library::describe); // Automatically builds library before us and optionally adds its products to our target.
    // ...
}

The __FILE__ macro may be abused to properly & automatically detect target root directories.

Some relatively unintrusive choices (I really don't want to bundle another big library, MSVC discovery is already insane as is) would be ETW/Concurrency Visualizer on Windows (cvmarkersobj.h) and DTrace/perf markers on Linux.

References:
https://docs.microsoft.com/en-us/visualstudio/profiling/concurrency-visualizer-sdk?view=vs-2017
http://dtrace.org/guide/chp-usdt.html
https://github.com/jlfwong/speedscope/wiki/Importing-from-perf-(linux)

Probably want to exclude it from the enumerated sources list.

Your usual thing for command line programs: switches, options etc. We need:

• some defaults,
• facilities to add options from target descriptions for configurable targets,
• facilities to override defaults from targets,
• facilities to set them from the command line.

I can see a possible use for a mode where cppbuild cannot rebuild itself, but can still build the project it was originally compiled to build.

Using response files will allow detection of targets in need of rebuild when their command lines change due to e.g. changed configuration.

The @file syntax is supported by all three major compilers (gcc, clang, MSVC).

Only old traces remain, not logs.

This happened when deleting cbl_detail.h and building on Linux.

Potentially also an exponential back-off.