C#: Use ref conversions (including variance conversions) for element types of span conversions.

michaelnebel · michaelnebel · commit a991afdf697a · 2026-01-07T09:55:10.000+01:00
diff --git a/csharp/ql/lib/semmle/code/csharp/Conversion.qll b/csharp/ql/lib/semmle/code/csharp/Conversion.qll
@@ -533,9 +533,7 @@ predicate convSpan(Type fromType, Type toType) {
     ) and
     toElementType = toType.(ReadOnlySpanType).getElementType()
   |
-    convIdentity(fromElementType, toElementType)
-    or
-    convVariance(fromElementType, toElementType)
+    convRefTypeNonNull(fromElementType, toElementType)
   )
   or
   fromType instanceof SystemStringClass and

Original file line number	Diff line number	Diff line change
`@@ -533,9 +533,7 @@ predicate convSpan(Type fromType, Type toType) {`
`533`	`533`	`) and`
`534`	`534`	`toElementType = toType.(ReadOnlySpanType).getElementType()`
`535`	`535`	`\|`
`536`		`- convIdentity(fromElementType, toElementType)`
`537`		`- or`
`538`		`- convVariance(fromElementType, toElementType)`
	`536`	`+ convRefTypeNonNull(fromElementType, toElementType)`
`539`	`537`	`)`
`540`	`538`	`or`
`541`	`539`	`fromType instanceof SystemStringClass and`