BlobBuilder.Align(int) seems not working on mono

[buyaa-n]

A Field RVA alignment test is failing on mono legs in this PR

That verifies the code section:

runtime/src/libraries/System.Reflection.Emit/src/System/Reflection/Emit/ModuleBuilderImpl.cs

Lines 452 to 454 in f36b7cd

	_metadataBuilder.AddFieldRelativeVirtualAddress(handle, fieldDataBuilder.Count);
	fieldDataBuilder.WriteBytes(field._rvaData!);
	fieldDataBuilder.Align(ManagedPEBuilder.MappedFieldDataAlignment);

Not sure if it is bug or expected, I don't see mono specific code in MetadataBuilder nor in BlobBuilder.Align(int)

runtime/src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/BlobBuilder.cs

Lines 808 to 812 in 72c4c57

	public void Align(int alignment)
	{
	int position = Count;
	WriteBytes(0, BitArithmetic.Align(position, alignment) - position);
	}

[lambdageek]

It's probably an issue on the reading side - maybe somewhere in https://github.com/dotnet/runtime/blob/main/src/mono/mono/metadata/class.c#L5580-L5649

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Issue Details

---

A Field RVA alignment test is failing on mono legs in this PR

That verifies the code section:

runtime/src/libraries/System.Reflection.Emit/src/System/Reflection/Emit/ModuleBuilderImpl.cs

Lines 452 to 454 in f36b7cd

	_metadataBuilder.AddFieldRelativeVirtualAddress(handle, fieldDataBuilder.Count);
	fieldDataBuilder.WriteBytes(field._rvaData!);
	fieldDataBuilder.Align(ManagedPEBuilder.MappedFieldDataAlignment);

Not sure if it is bug or expected, I don't see mono specific code in MetadataBuilder nor in BlobBuilder.Align(int)

runtime/src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/BlobBuilder.cs

Lines 808 to 812 in 72c4c57

	public void Align(int alignment)
	{
	int position = Count;
	WriteBytes(0, BitArithmetic.Align(position, alignment) - position);
	}

Author:	buyaa-n
Assignees:	-
Labels:	area-System.Reflection, runtime-mono, area-System.Reflection-mono
Milestone:	9.0.0