Update RSPEC

rules/S7462/rust/metadata.json

@@ -1,12 +1,13 @@
 {
-  "title": "FIXME",
-  "type": "CODE_SMELL",
+  "title": "`mem::uninitialized` and `mem::zeroed()` should not be used to replace values",
+  "type": "BUG",
   "status": "ready",
   "remediation": {
     "func": "Constant\/Issue",
     "constantCost": "5min"
   },
   "tags": [
+    "clippy"
   ],
   "defaultSeverity": "Major",
   "ruleSpecification": "RSPEC-7462",
@@ -16,10 +17,8 @@
   "quickfix": "unknown",
   "code": {
     "impacts": {
-      "MAINTAINABILITY": "HIGH",
-      "RELIABILITY": "MEDIUM",
-      "SECURITY": "LOW"
+      "RELIABILITY": "MEDIUM"
     },
-    "attribute": "CONVENTIONAL"
+    "attribute": "LOGICAL"
   }
 }

rules/S7462/rust/rule.adoc

@@ -1,16 +1,6 @@
-FIXME: add a description
-
-// If you want to factorize the description uncomment the following line and create the file.
-//include::../description.adoc[]
-
 == Why is this an issue?
 
-FIXME: remove the unused optional headers (that are commented out)
-
-//=== What is the potential impact?
-
-== How to fix it
-//== How to fix it in FRAMEWORK NAME
+Using ``++mem::replace(&mut _, mem::uninitialized())++`` or ``++mem::replace(&mut _, mem::zeroed())++`` leads to undefined behavior even if the value is overwritten later. This is because the uninitialized value might be observed in the case of a panic, which can lead to unpredictable and dangerous consequences in your program.
 
 === Code examples
 
@@ -18,27 +8,34 @@ FIXME: remove the unused optional headers (that are commented out)
 
 [source,rust,diff-id=1,diff-type=noncompliant]
 ----
-FIXME
+use std::mem;
+
+fn may_panic(v: Vec<i32>) -> Vec<i32> { v }
+
+#[allow(deprecated, invalid_value)]
+fn myfunc(v: &mut Vec<i32>) {
+    let taken_v = unsafe { mem::replace(v, mem::uninitialized()) }; // Noncompliant
+    let new_v = may_panic(taken_v); // undefined behavior on panic
+    mem::forget(mem::replace(v, new_v));
+}
 ----
 
 ==== Compliant solution
 
 [source,rust,diff-id=1,diff-type=compliant]
 ----
-FIXME
+use std::mem;
+use take_mut::take;
+
+fn may_panic(v: Vec<i32>) -> Vec<i32> { v }
+
+fn myfunc(v: &mut Vec<i32>) {
+    let new_v = take(v, |old_v| may_panic(old_v)); // Compliant
+    mem::forget(mem::replace(v, new_v));
+}
 ----
 
-//=== How does this work?
+== Resources
+=== Documentation
 
-//=== Pitfalls
-
-//=== Going the extra mile
-
-
-//== Resources
-//=== Documentation
-//=== Articles & blog posts
-//=== Conference presentations
-//=== Standards
-//=== External coding guidelines
-//=== Benchmarks
+* Clippy Lints - https://rust-lang.github.io/rust-clippy/master/index.html#mem_replace_with_uninit