Use u8 in more places

[stephentoub]

Primarily replacing Encoding.UTF8/ASCII.GetBytes("literal") with "literal"u8.ToArray()

Updates the pinned version of the C# compiler we're using so that we pick up recent updates to the u8 feature.

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Issue Details

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Primarily replacing Encoding.UTF8/ASCII.GetBytes("literal") with "literal"u8.ToArray()

Updates the pinned version of the C# compiler we're using so that we pick up recent updates to the u8 feature.

Author:	stephentoub
Assignees:	stephentoub
Labels:	area-Meta
Milestone:	-

[vcsjones]

One more, if you are interested in throwing it in this PR:

runtime/src/libraries/System.Security.Cryptography/src/System/Security/Cryptography/X509Certificates/AppleCertificatePal.Pem.iOS.cs

Line 14 in c12bea8

private static ReadOnlySpan<byte> PemBegin => new byte[] { 0x2D, 0x2D, 0x2D, 0x2D, 0x2D, 0x42, 0x45, 0x47, 0x49, 0x4E, 0x20 };

You could probably get rid of that property entirely and change line 30 to:

if (rawData.IndexOf("-----BEGIN "u8) < 0)

(Assuming my understanding is correct that the "string"u8 syntax makes use of the same "Get ReadOnlySpan<byte> from the .TEXT section of the binary".

[stephentoub]

@tannergooding, this pulls in an updated C# compiler, and there are a fair number of failures in UIntPtr-related tests, e.g.

runtime/src/libraries/System.Runtime/tests/System/DoubleTests.GenericMath.cs

Line 1869 in 748dfb7

AssertBitwiseEqual(9223372036854775807.0, NumberBaseHelper<double>.CreateTruncating<nuint>(unchecked((nuint)0x7FFFFFFFFFFFFFFF)));

    System.Tests.DoubleTests_GenericMath.CreateCheckedFromUIntPtrTest [FAIL]
      Assert.Equal() Failure
      Expected: 9.2233720368547758E+18
      Actual:   4294967295
      Stack Trace:
        /_/src/libraries/System.Runtime/tests/System/DoubleTests.GenericMath.cs(31,0): at System.Tests.DoubleTests_GenericMath.AssertBitwiseEqual(Double expected, Double actual)
        /_/src/libraries/System.Runtime/tests/System/DoubleTests.GenericMath.cs(1293,0): at System.Tests.DoubleTests_GenericMath.CreateCheckedFromUIntPtrTest()
        /_/src/mono/System.Private.CoreLib/src/System/Reflection/MethodInvoker.Mono.cs(33,0): at System.Reflection.MethodInvoker.InterpretedInvoke(Object obj, Span`1 args, BindingFlags invokeAttr)
    System.Tests.DoubleTests_GenericMath.CreateTruncatingFromUIntPtrTest [FAIL]
      Assert.Equal() Failure
      Expected: 9.2233720368547758E+18
      Actual:   4294967295
      Stack Trace:
        /_/src/libraries/System.Runtime/tests/System/DoubleTests.GenericMath.cs(31,0): at System.Tests.DoubleTests_GenericMath.AssertBitwiseEqual(Double expected, Double actual)
        /_/src/libraries/System.Runtime/tests/System/DoubleTests.GenericMath.cs(1869,0): at System.Tests.DoubleTests_GenericMath.CreateTruncatingFromUIntPtrTest()
        /_/src/mono/System.Private.CoreLib/src/System/Reflection/MethodInvoker.Mono.cs(33,0): at System.Reflection.MethodInvoker.InterpretedInvoke(Object obj, Span`1 args, BindingFlags invokeAttr)
    System.Tests.DoubleTests_GenericMath.CreateSaturatingFromUIntPtrTest [FAIL]
      Assert.Equal() Failure
      Expected: 9.2233720368547758E+18
      Actual:   4294967295
      Stack Trace:
        /_/src/libraries/System.Runtime/tests/System/DoubleTests.GenericMath.cs(31,0): at System.Tests.DoubleTests_GenericMath.AssertBitwiseEqual(Double expected, Double actual)
        /_/src/libraries/System.Runtime/tests/System/DoubleTests.GenericMath.cs(1581,0): at System.Tests.DoubleTests_GenericMath.CreateSaturatingFromUIntPtrTest()
        /_/src/mono/System.Private.CoreLib/src/System/Reflection/MethodInvoker.Mono.cs(33,0): at System.Reflection.MethodInvoker.InterpretedInvoke(Object obj, Span`1 args, BindingFlags invokeAttr)

There are some commented out tests there:

runtime/src/libraries/System.Runtime/tests/System/DoubleTests.GenericMath.cs

Lines 1871 to 1873 in 748dfb7

	// https://github.com/dotnet/roslyn/issues/60714
	// AssertBitwiseEqual(9223372036854775808.0, NumberBaseHelper<double>.CreateTruncating<nuint>(unchecked((nuint)0x8000000000000000)));
	// AssertBitwiseEqual(18446744073709551615.0, NumberBaseHelper<double>.CreateTruncating<nuint>(unchecked((nuint)0xFFFFFFFFFFFFFFFF)));

with a comment to a Roslyn bug recently fixed, but I'm assuming the tests that aren't commented out are expected to continue working?

So far all the failures I've seen have been on Unix on mono.

[tannergooding]

Same as for #70087 (comment)

This looks like an issue similar to #69795.

I'd recommend disabling them just for Mono since its handling it incorrectly (looks like its always treating the target type as int/uint even on 64-bit systems)