Error map
Deprecated null to internal Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated
PHP · layer 4, Application & API
Centre: this error. First ring: errors it is linked with (9). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.
Directly related (9)
Fatal error: Uncaught TypeError: Unsupported operand types: string + int
An arithmetic or array operator was used with incompatible types (PHP 8 is stricter than PHP 7).
WordPress on PHP 8: Fatal error: Uncaught Error: Call to undefined function create_function() / each()
An old plugin/theme uses functions removed in PHP 8 (create_function, each), so the site breaks after a PHP upgrade.
Deprecated: Implicit conversion from float 2.5 to int loses precision
PHP 8.1+ warns when a float with a fractional part is silently converted to int (array keys, % operator, int parameters).
DeprecationWarning: Buffer() is deprecated due to security and usability issues (DEP0005)
Code (yours or a dependency) uses the deprecated new Buffer() constructor.
npm WARN deprecated package@1.2.3: This package is no longer supported.
A dependency (often a transitive one) is deprecated by its author.
npm WARN config global `--global`, `--local` are deprecated. Use `--location=global` instead.
A deprecation warning printed by npm 8.11–8.12 for the --global flag.
Deprecated: Creation of dynamic property Foo::$bar is deprecated
PHP 8.2+ deprecates creating properties that aren’t declared in the class.
DeprecationWarning: The `punycode` module is deprecated (DEP0040)
A dependency imports Node’s built-in punycode module, deprecated since Node 21.
WARN: the attribute `version` is obsolete, it will be ignored
A harmless Compose v2 warning: the top-level version: line in docker-compose.yml is no longer used.
Two steps away (25)
java.lang.ClassCastException: class A cannot be cast to class B
An object was cast to a type it isn’t.
Fatal error: Uncaught TypeError: foo(): Argument #1 ($x) must be of type int, string given
A function received a value of the wrong type for a typed parameter.
Warning: Array to string conversion
An array was used where a string is expected — echoing it, concatenating it, or passing it to a string function.
PHP Fatal error: Uncaught Error: Call to undefined function
PHP can’t find the function you called — usually a missing extension, missing include, or namespace issue.
WordPress: There Has Been a Critical Error on This Website
A PHP fatal error (usually from a plugin or theme) stopped WordPress; the real error is in the debug log or recovery-mode email.
WordPress: Installation failed: Could not create directory (plugin/theme install or update)
WordPress can’t write to wp-content/plugins, themes or upgrade — ownership/permissions or disk space.
Fatal error: Uncaught Error: Cannot use object of type stdClass as array
Code used array syntax (`$x['key']`) on an object.
System.InvalidCastException: Unable to cast object of type 'X' to type 'Y'
An explicit cast failed because the object’s runtime type isn’t the target type.
Swift: Cannot convert value of type 'X' to expected argument type 'Y'
The value’s type doesn’t match what the function or property expects.
Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client
An Express/Node handler tried to send a second response (or set headers) after one was already sent.
TypeError [ERR_IMPORT_ATTRIBUTE_MISSING]: Module needs an import attribute of "type: json"
An ES module imported a .json file without the required import attribute.
Error: Unhandled 'error' event (events.js / node:events)
An EventEmitter (stream, socket, child process, server) emitted 'error' and nothing listened for it, so Node crashed.
npm ERR! code ERESOLVE — unable to resolve dependency tree
npm 7+ found conflicting peer dependency requirements and refuses to install a broken tree.
npm ERR! code E404 — 404 Not Found: package@version is not in this registry
npm asked the registry for a package (or version) that doesn’t exist there — a typo, a private/scoped package without auth, or th…
npm ERR! code ETARGET — No matching version found for package@^9.9.9
The version range in package.json doesn’t match any published version of the package.
Authentication plugin 'caching_sha2_password' cannot be loaded
An old MySQL client/driver can’t use MySQL 8’s default authentication plugin.
npm WARN old lockfile — The package-lock.json file was created with an old version of npm, so supplemental metadata must be fetched
The lockfile is lockfileVersion 1 (npm 6) and npm 7+ is upgrading it.
npm ERR! cb() never called!
An old npm crash during install — usually network/cache corruption.
Warning: componentWillMount has been renamed, and is not recommended for use.
A class component uses legacy lifecycle methods (componentWillMount/WillReceiveProps/WillUpdate).
Error: Cannot find module 'x' (MODULE_NOT_FOUND)
Node can’t resolve the module path — the package isn’t installed, or a relative path/extension is wrong.
Gradle: Could not resolve all files for configuration / Could not resolve dependency
Gradle couldn’t download a dependency — wrong coordinates/version, missing repository, offline mode, or network/proxy issues.
java.lang.ClassNotFoundException / NoClassDefFoundError
The JVM couldn’t find a class on the classpath at runtime.
docker compose: services.x Additional property y is not allowed / yaml: line N: mapping values are not allowed
The compose file is invalid YAML or uses a key Compose doesn’t recognise at that level (usually an indentation mistake).
Warning: Support for defaultProps will be removed from function components in a future major release.
A function component (often inside a library) uses Component.defaultProps.
Warning: findDOMNode is deprecated and will be removed in the next major release.
A component (often an old library like react-transition-group v1, react-draggable) uses findDOMNode, which StrictMode flags and R…
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