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+# Frequently Asked Questions
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+
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+<!--
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+@cond TURN_OFF_DOXYGEN
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+-->
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+# Table of Contents
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+
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+* [Introduction](#introduction)
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+* [FAQ](#faq)
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+ * [Why is my debug build on Windows so slow?](#why-is-my-debug-build-on-windows-so-slow)
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+<!--
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+@endcond TURN_OFF_DOXYGEN
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+-->
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+
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+# Introduction
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+
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+This is a constantly updated section where I'll try to put the answers to the
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+most frequently asked questions.<br/>
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+If you don't find your answer here, there are two cases: nobody has done it yet
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+or this section needs updating. In both cases, try to
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+[open a new issue](https://github.com/skypjack/entt/issues/new) or enter the
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+[gitter channel](https://gitter.im/skypjack/entt) and ask your question.
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+Probably someone already has an answer for you and we can then integrate this
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+part of the documentation.
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+
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+# FAQ
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+
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+## Why is my debug build on Windows so slow?
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+
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+`EnTT` is an experimental project that I also use to keep me up-to-date with the
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+latest revision of the language and the standard library. For this reason, it's
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+likely that some classes you're working with are using standard containers under
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+the hood.<br/>
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+Unfortunately, it's known that the standard containers aren't particularly
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+performing in debugging (the reasons for this go beyond this document) and are
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+even less so on Windows apparently. Fortunately this can also be mitigated a
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+lot, achieving good results in many cases.
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+
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+First of all, there are two things to do in a Windows project:
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+
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+* Disable the [`/JMC`](https://docs.microsoft.com/cpp/build/reference/jmc)
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+ option (_Just My Code_ debugging), available starting in Visual Studio 2017
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+ version 15.8.
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+
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+* Set the [`_ITERATOR_DEBUG_LEVEL`](https://docs.microsoft.com/cpp/standard-library/iterator-debug-level)
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+ macro to 0. This will disable checked iterators and iterator debugging.
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+
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+Moreover, the macro `ENTT_DISABLE_ASSERT` should be defined to disable internal
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+checks made by `EnTT` in debug. These are asserts introduced to help the users,
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+but require to access to the underlying containers and therefore risk ruining
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+the performance in some cases.
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+
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+With these changes, debug performance should increase enough for most cases. If
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+you want something more, you can can also switch to an optimization level `O0`
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+or preferably `O1`.
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Michele Caini