{"record":{"id":"fea7d133083d70f6","repo":"bevyengine/bevy","slug":"attempted-to-initialize-invalid-bits-as-an-entity-fea7d1","errorCode":null,"errorMessage":"Attempted to initialize invalid bits as an entity","messagePattern":"Attempted to initialize invalid bits as an entity","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"error","filePath":"crates/bevy_ecs/src/entity/mod.rs","lineNumber":582,"sourceCode":"    /// No particular structure is guaranteed for the returned bits.\n    #[inline(always)]\n    pub const fn to_bits(self) -> u64 {\n        self.index.to_bits() as u64 | ((self.generation.to_bits() as u64) << 32)\n    }\n\n    /// Reconstruct an `Entity` previously destructured with [`Entity::to_bits`].\n    ///\n    /// Only useful when applied to results from `to_bits` in the same instance of an application.\n    ///\n    /// # Panics\n    ///\n    /// This method will likely panic if given `u64` values that did not come from [`Entity::to_bits`].\n    #[inline]\n    pub const fn from_bits(bits: u64) -> Self {\n        if let Some(id) = Self::try_from_bits(bits) {\n            id\n        } else {\n            panic!(\"Attempted to initialize invalid bits as an entity\")\n        }\n    }\n\n    /// Reconstruct an `Entity` previously destructured with [`Entity::to_bits`].\n    ///\n    /// Only useful when applied to results from `to_bits` in the same instance of an application.\n    ///\n    /// This method is the fallible counterpart to [`Entity::from_bits`].\n    #[inline(always)]\n    pub const fn try_from_bits(bits: u64) -> Option<Self> {\n        let raw_index = bits as u32;\n        let raw_gen = (bits >> 32) as u32;\n\n        if let Some(index) = EntityIndex::try_from_bits(raw_index) {\n            Some(Self {\n                index,\n                generation: EntityGeneration::from_bits(raw_gen),\n            })","sourceCodeStart":564,"sourceCodeEnd":600,"githubUrl":"https://github.com/bevyengine/bevy/blob/396ca727080776bd313bb892423b7d94e03b81b4/crates/bevy_ecs/src/entity/mod.rs#L564-L600","documentation":"Runtime panic from Entity::from_bits: the u64 argument does not decode to a valid Entity — the index bits equal the reserved invalid value or the combined index/generation bit pattern is not one ever handed out by this World. The doc comment on the method warns it will 'likely panic' for values not sourced from Entity::to_bits.","triggerScenarios":"Thrown at crates/bevy_ecs/src/entity/mod.rs:582 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":["Use only bits obtained from Entity::to_bits within the same application instance","For cross-run or networked ids, serialize index and generation explicitly and validate them against Entities::contains or world validation APIs","Avoid hand-constructing u64 bit patterns for entities"],"exampleFix":null,"handlingStrategy":"validation","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"396ca727080776bd313bb892423b7d94e03b81b4","analyzedAt":"2026-08-20T16:12:39.808Z","contentChangedAt":"2026-08-20T16:12:39.808Z","schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}