{"id":6648,"date":"2022-09-04T10:53:09","date_gmt":"2022-09-04T05:23:09","guid":{"rendered":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/"},"modified":"2022-09-04T10:53:09","modified_gmt":"2022-09-04T05:23:09","slug":"solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory","status":"publish","type":"post","link":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/","title":{"rendered":"[Solved] C &#8211; How can a pointer overwrite a local const block of memory but not the global const block of memory?"},"content":{"rendered":"<p> [ad_1]<br \/>\n<\/p>\n<div id=\"answer-64650340\" class=\"answer js-answer accepted-answer js-accepted-answer\" data-answerid=\"64650340\" data-parentid=\"64650095\" data-score=\"1\" data-position-on-page=\"2\" data-highest-scored=\"0\" data-question-has-accepted-highest-score=\"0\" itemprop=\"suggestedAnswer\" itemscope itemtype=\"https:\/\/schema.org\/Answer\">\n<div class=\"post-layout\">\n<div class=\"votecell post-layout--left\"><\/div>\n<div class=\"answercell post-layout--right\">\n<div class=\"s-prose js-post-body\" itemprop=\"text\">\n<p>It is completely up to the implementation. For example, <code>const<\/code> data on bare metal ARM uCs is stored in the FLASH memory. You can write to there but it will have no effect at all.<\/p>\n<p>Hosted systems will behave differently depending on the OS, its version and hardware.<\/p>\n<p><em><strong><code>How can I overwrite a const block of memory<\/code><\/strong><\/em> simply if you want to write do not declare it <code>const<\/code>. If you do respect the promise given to the compiler.<\/p>\n<p>If it is just curiosity of the beginner, there is no other way than experimenting. Experiment, debug and try to interpret the result.<\/p>\n<p>EDIT.<\/p>\n<p>In most common implementations:<\/p>\n<ul>\n<li>\n<p>constant local (automatic variables are created on the stack which is not protected by the operating system against writing &#8211; you are not getting the segfault.<\/p>\n<\/li>\n<li>\n<p>constant global (static storage) variables are placed in the <code>.rodata<\/code> segment which is protected by the operating system against writing &#8211; you are getting the segfault.<\/p>\n<\/li>\n<\/ul>\n<\/div>\n<div class=\"mt24\"><\/div>\n<\/div>\n<p>            <span class=\"d-none\" itemprop=\"commentCount\">6<\/span> <\/p><\/div>\n<\/div>\n<p>[ad_2]<\/p>\n<p>solved C &#8211; How can a pointer overwrite a local const block of memory but not the global const block of memory? <\/p>\n","protected":false},"excerpt":{"rendered":"<p>[ad_1] It is completely up to the implementation. For example, const data on bare metal ARM uCs is stored in the FLASH memory. You can write to there but it will have no effect at all. Hosted systems will behave differently depending on the OS, its version and hardware. How can I overwrite a const &#8230; <a title=\"[Solved] C &#8211; How can a pointer overwrite a local const block of memory but not the global const block of memory?\" class=\"read-more\" href=\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/\" aria-label=\"More on [Solved] C &#8211; How can a pointer overwrite a local const block of memory but not the global const block of memory?\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[320],"tags":[324,1635,712],"class_list":["post-6648","post","type-post","status-publish","format-standard","hentry","category-solved","tag-c","tag-constants","tag-pointers"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.5 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>[Solved] C - How can a pointer overwrite a local const block of memory but not the global const block of memory? - JassWeb<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"[Solved] C - How can a pointer overwrite a local const block of memory but not the global const block of memory? - JassWeb\" \/>\n<meta property=\"og:description\" content=\"[ad_1] It is completely up to the implementation. For example, const data on bare metal ARM uCs is stored in the FLASH memory. You can write to there but it will have no effect at all. Hosted systems will behave differently depending on the OS, its version and hardware. How can I overwrite a const ... Read more\" \/>\n<meta property=\"og:url\" content=\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/\" \/>\n<meta property=\"og:site_name\" content=\"JassWeb\" \/>\n<meta property=\"article:published_time\" content=\"2022-09-04T05:23:09+00:00\" \/>\n<meta name=\"author\" content=\"Kirat\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Kirat\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/#article\",\"isPartOf\":{\"@id\":\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/\"},\"author\":{\"name\":\"Kirat\",\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/person\/65c9c7b7958150c0dc8371fa35dd7c31\"},\"headline\":\"[Solved] C &#8211; How can a pointer overwrite a local const block of memory but not the global const block of memory?\",\"datePublished\":\"2022-09-04T05:23:09+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/\"},\"wordCount\":192,\"publisher\":{\"@id\":\"https:\/\/jassweb.com\/solved\/#organization\"},\"keywords\":[\"c++\",\"constants\",\"pointers\"],\"articleSection\":[\"Solved\"],\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/\",\"url\":\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/\",\"name\":\"[Solved] C - How can a pointer overwrite a local const block of memory but not the global const block of memory? - JassWeb\",\"isPartOf\":{\"@id\":\"https:\/\/jassweb.com\/solved\/#website\"},\"datePublished\":\"2022-09-04T05:23:09+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/jassweb.com\/solved\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"[Solved] C &#8211; How can a pointer overwrite a local const block of memory but not the global const block of memory?\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/jassweb.com\/solved\/#website\",\"url\":\"https:\/\/jassweb.com\/solved\/\",\"name\":\"JassWeb\",\"description\":\"Build High-quality Websites\",\"publisher\":{\"@id\":\"https:\/\/jassweb.com\/solved\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/jassweb.com\/solved\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/jassweb.com\/solved\/#organization\",\"name\":\"Jass Web\",\"url\":\"https:\/\/jassweb.com\/solved\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/jassweb.com\/wp-content\/uploads\/2021\/02\/jass-website-logo-1.png\",\"contentUrl\":\"https:\/\/jassweb.com\/wp-content\/uploads\/2021\/02\/jass-website-logo-1.png\",\"width\":693,\"height\":132,\"caption\":\"Jass Web\"},\"image\":{\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/logo\/image\/\"}},{\"@type\":\"Person\",\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/person\/65c9c7b7958150c0dc8371fa35dd7c31\",\"name\":\"Kirat\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/jassweb.com\/solved\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/jassweb.com\/solved\/wp-content\/litespeed\/avatar\/1261af3c9451399fa1336d28b98ea3bb.jpg?ver=1776403586\",\"contentUrl\":\"https:\/\/jassweb.com\/solved\/wp-content\/litespeed\/avatar\/1261af3c9451399fa1336d28b98ea3bb.jpg?ver=1776403586\",\"caption\":\"Kirat\"},\"sameAs\":[\"http:\/\/jassweb.com\"],\"url\":\"https:\/\/jassweb.com\/solved\/author\/jaspritsinghghumangmail-com\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"[Solved] C - How can a pointer overwrite a local const block of memory but not the global const block of memory? - JassWeb","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/","og_locale":"en_US","og_type":"article","og_title":"[Solved] C - How can a pointer overwrite a local const block of memory but not the global const block of memory? - JassWeb","og_description":"[ad_1] It is completely up to the implementation. For example, const data on bare metal ARM uCs is stored in the FLASH memory. You can write to there but it will have no effect at all. Hosted systems will behave differently depending on the OS, its version and hardware. How can I overwrite a const ... Read more","og_url":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/","og_site_name":"JassWeb","article_published_time":"2022-09-04T05:23:09+00:00","author":"Kirat","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Kirat","Est. reading time":"1 minute"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/#article","isPartOf":{"@id":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/"},"author":{"name":"Kirat","@id":"https:\/\/jassweb.com\/solved\/#\/schema\/person\/65c9c7b7958150c0dc8371fa35dd7c31"},"headline":"[Solved] C &#8211; How can a pointer overwrite a local const block of memory but not the global const block of memory?","datePublished":"2022-09-04T05:23:09+00:00","mainEntityOfPage":{"@id":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/"},"wordCount":192,"publisher":{"@id":"https:\/\/jassweb.com\/solved\/#organization"},"keywords":["c++","constants","pointers"],"articleSection":["Solved"],"inLanguage":"en-US"},{"@type":"WebPage","@id":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/","url":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/","name":"[Solved] C - How can a pointer overwrite a local const block of memory but not the global const block of memory? - JassWeb","isPartOf":{"@id":"https:\/\/jassweb.com\/solved\/#website"},"datePublished":"2022-09-04T05:23:09+00:00","breadcrumb":{"@id":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/jassweb.com\/solved\/solved-c-how-can-a-pointer-overwrite-a-local-const-block-of-memory-but-not-the-global-const-block-of-memory\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/jassweb.com\/solved\/"},{"@type":"ListItem","position":2,"name":"[Solved] C &#8211; How can a pointer overwrite a local const block of memory but not the global const block of memory?"}]},{"@type":"WebSite","@id":"https:\/\/jassweb.com\/solved\/#website","url":"https:\/\/jassweb.com\/solved\/","name":"JassWeb","description":"Build High-quality Websites","publisher":{"@id":"https:\/\/jassweb.com\/solved\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/jassweb.com\/solved\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/jassweb.com\/solved\/#organization","name":"Jass Web","url":"https:\/\/jassweb.com\/solved\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/jassweb.com\/solved\/#\/schema\/logo\/image\/","url":"https:\/\/jassweb.com\/wp-content\/uploads\/2021\/02\/jass-website-logo-1.png","contentUrl":"https:\/\/jassweb.com\/wp-content\/uploads\/2021\/02\/jass-website-logo-1.png","width":693,"height":132,"caption":"Jass Web"},"image":{"@id":"https:\/\/jassweb.com\/solved\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/jassweb.com\/solved\/#\/schema\/person\/65c9c7b7958150c0dc8371fa35dd7c31","name":"Kirat","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/jassweb.com\/solved\/#\/schema\/person\/image\/","url":"https:\/\/jassweb.com\/solved\/wp-content\/litespeed\/avatar\/1261af3c9451399fa1336d28b98ea3bb.jpg?ver=1776403586","contentUrl":"https:\/\/jassweb.com\/solved\/wp-content\/litespeed\/avatar\/1261af3c9451399fa1336d28b98ea3bb.jpg?ver=1776403586","caption":"Kirat"},"sameAs":["http:\/\/jassweb.com"],"url":"https:\/\/jassweb.com\/solved\/author\/jaspritsinghghumangmail-com\/"}]}},"_links":{"self":[{"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/posts\/6648","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/comments?post=6648"}],"version-history":[{"count":0,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/posts\/6648\/revisions"}],"wp:attachment":[{"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/media?parent=6648"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/categories?post=6648"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jassweb.com\/solved\/wp-json\/wp\/v2\/tags?post=6648"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}