string.Intern works inconsistently with NativeAOT #12447
Description
Description
ReferenceEquals("ab", string.Intern(new StringBuilder().Append('a').Append('b').ToString())) returns true on coreclr and false with NativeAOT. The official documentation page https://learn.microsoft.com/en-us/dotnet/api/system.string.intern?view=net-9.0 states that it would return true.
Reproduction Steps
- copy-paste example from documentation:
// Sample for String.Intern(String)
using System;
using System.Text;
class Sample
{
public static void Main()
{
string s1 = "MyTest";
string s2 = new StringBuilder().Append("My").Append("Test").ToString();
string s3 = String.Intern(s2);
Console.WriteLine($"s1 == {s1}");
Console.WriteLine($"s2 == {s2}");
Console.WriteLine($"s3 == {s3}");
Console.WriteLine($"Is s2 the same reference as s1?: {(Object)s2 == (Object)s1}");
Console.WriteLine($"Is s3 the same reference as s1?: {(Object)s3 == (Object)s1}");
}
}
/*
This example produces the following results:
s1 == MyTest
s2 == MyTest
s3 == MyTest
Is s2 the same reference as s1?: False
Is s3 the same reference as s1?: True
*/
- Run with NativeAOT, observe the following output:
s1 == MyTest
s2 == MyTest
s3 == MyTest
Is s2 the same reference as s1?: False
Is s3 the same reference as s1?: False
Expected behavior
NativeAOT is consistent with CoreCLR
Actual behavior
Liternal strings are not actually interned
Regression?
I guess? It worked since .NET Framework days.
Known Workarounds
No response
Configuration
.NET 10
Other information
No response
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