Add constant with compiler flags #15611
Description
I'd like a constant with compiler flags so I can print build info when my process is starting. Today I do
{% begin %}
{%
flags = [] of String
flags << "-Dpreview_mt" if flag?(:preview_mt)
flags << "-Dmt" if flag?(:mt)
flags << "-Dexecution_context" if flag?(:execution_context)
flags << "-Drelease" if flag?(:release)
flags << "-Dtracing" if flag?(:tracing)
flags << "-Dperf_tools" if flag?(:perf_tools)
%}
puts "Built with #{Crystal::VERSION} #{Crystal::BUILD_COMMIT} {{flags.join(" ").id}}"
{% end %}which needs to be updated as I start using new flags. I'd like something like
puts "Built with #{Crystal::VERSION} #{Crystal::BUILD_COMMIT} #{Crystal::COMPILER_FLAGS.join(" ")}"