On Sunday, 19 June 2016 at 19:53:46 UTC, Gary Willoughby wrote:
When compiling, what exactly does the -betterC flag do? The command help says "omit generating some runtime information and helper functions" but what does this really mean? Is there any specifics somewhere?
My understanding was that -betterC was not fully implemented yet, due mostly to tight compiler integration with the runtime. (old info?)
I'm not super smart on the DMD source, but it looks like betterC prevents genhelpers() and genModuleInfo() from being called, with "helpers" appearing to be array checking, asserts and unit tests.
A comparison of object files compiled with and without the flags shows just a small reduction in the size of the code, but grepping for bounds checking, unit tests and ModuleInfo in the -betterC generated object file shows they are missing.
Hope this helps, -Jon
