{"id":1623,"date":"2009-05-06T16:59:54","date_gmt":"2009-05-06T06:59:54","guid":{"rendered":"http:\/\/www.flamingspork.com\/blog\/?p=1623"},"modified":"2016-08-22T15:09:36","modified_gmt":"2016-08-22T05:09:36","slug":"c-stl-bitset-only-useful-for-known-at-compile-time-number-of-bits","status":"publish","type":"post","link":"https:\/\/www.flamingspork.com\/blog\/2009\/05\/06\/c-stl-bitset-only-useful-for-known-at-compile-time-number-of-bits\/","title":{"rendered":"c++ stl bitset only useful for known-at-compile-time number of bits"},"content":{"rendered":"

Found in the libstdc++ docs<\/a>:<\/p>\n

Extremely weird solutions. If you have access to the compiler and linker at runtime, you can do something insane, like figuring out just how many bits you need, then writing a temporary source code file. That file contains an instantiation of bitset for the required number of bits, inside some wrapper functions with unchanging signatures. Have your program then call the compiler on that file using Position Independent Code, then open the newly-created object file and load those wrapper functions. You’ll have an instantiation of bitset for the exact N that you need at the time. Don’t forget to delete the temporary files. (Yes, this can be, and has been, done.)<\/p><\/blockquote>\n

Oh yeah – feel the love.<\/p>\n

Brought to you by the stl-is-often-worse-for-you-than-meth dept.<\/p>\n","protected":false},"excerpt":{"rendered":"

Found in the libstdc++ docs: Extremely weird solutions. If you have access to the compiler and linker at runtime, you can do something insane, like figuring out just how many bits you need, then writing a temporary source code file. … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[76,75,18],"tags":[],"class_list":["post-1623","post","type-post","status-publish","format-standard","hentry","category-code","category-drizzle-work-et-al","category-grumble"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p5a6n8-qb","jetpack-related-posts":[{"id":2323,"url":"https:\/\/www.flamingspork.com\/blog\/2011\/03\/17\/things-ive-done-in-drizzle\/","url_meta":{"origin":1623,"position":0},"title":"Things I’ve done in Drizzle","author":"Stewart Smith","date":"2011-03-17","format":false,"excerpt":"When writing my Dropping ACID: Eating Data in a Web 2.0 Cloud World talk for LCA2011 I came to the realisation that I had forgotten a lot of the things I had worked on in MySQL and MySQL Cluster. 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GetFileSize, that's what I want to do!\" Except, of course,\u2026","rel":"","context":"In "grumble"","block_context":{"text":"grumble","link":"https:\/\/www.flamingspork.com\/blog\/category\/grumble\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":2196,"url":"https:\/\/www.flamingspork.com\/blog\/2010\/11\/15\/limiting-functions-to-32k-stack-in-drizzle-and-scoped_ptr\/","url_meta":{"origin":1623,"position":3},"title":"Limiting functions to 32k stack in Drizzle (and scoped_ptr)","author":"Stewart Smith","date":"2010-11-15","format":false,"excerpt":"I wonder if this comes under \"Code Style\" or not... Anyway, Monty and I finished getting Drizzle ready for adding \"\u00ef\u00bb\u00bf\u00ef\u00bb\u00bf\u00ef\u00bb\u00bf-Wframe-larger-than=32768\" as a standard compiler flag. 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