Add debug-only use of new AssemblyBuilder.Save in Regex.CompileToAssembly

[stephentoub]

To aid in debugging RegexCompiler issues and to help vet the new AssemblyBuilder.Save support.

This brings back and then tweaks code that was removed in #59734.

[ghost]

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Issue Details

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To aid in debugging RegexCompiler issues and to help vet the new AssemblyBuilder.Save support.

This brings back and then tweaks code that was removed in #59734.

Author:	stephentoub
Assignees:	-
Labels:	area-System.Text.RegularExpressions
Milestone:	-

[stephentoub]

@buyaa-n, the build is failing with:

/_/src/libraries/System.Reflection.Emit/src/System/Reflection/Emit/ModuleBuilderImpl.cs(190,9): Trim analysis error IL2121: System.Reflection.Emit.ModuleBuilderImpl.WriteInterfaceImplementations(TypeBuilderImpl, TypeDefinitionHandle): Unused 'UnconditionalSuppressMessageAttribute' for warning 'IL2072'. Consider removing the unused warning suppression. [D:\a\_work\1\s\src\libraries\sfx.proj]
/_/src/libraries/System.Reflection.Emit/src/System/Reflection/Emit/TypeBuilderImpl.cs(182,9): Trim analysis error IL2121: System.Reflection.Emit.TypeBuilderImpl.CheckInterfaces(Type[]): Unused 'UnconditionalSuppressMessageAttribute' for warning 'IL2075'. Consider removing the unused warning suppression. [D:\a\_work\1\s\src\libraries\sfx.proj]

Have you seen these?

[stephentoub]

@buyaa-n, I fixed the invalid code gen, but now I'm hitting this:

Unhandled exception. System.MissingMethodException: Method not found: 'System.ReadOnlySpan`1<Char> System.ReadOnlySpan`1.Slice(Int32)'

Is there something related to generics that's not yet implemented maybe?

[buyaa-n]

@buyaa-n, the build is failing with:

/_/src/libraries/System.Reflection.Emit/src/System/Reflection/Emit/ModuleBuilderImpl.cs(190,9): Trim analysis error IL2121: System.Reflection.Emit.ModuleBuilderImpl.WriteInterfaceImplementations(TypeBuilderImpl, TypeDefinitionHandle): Unused 'UnconditionalSuppressMessageAttribute' for warning 'IL2072'. Consider removing the unused warning suppression. [D:\a\_work\1\s\src\libraries\sfx.proj]
/_/src/libraries/System.Reflection.Emit/src/System/Reflection/Emit/TypeBuilderImpl.cs(182,9): Trim analysis error IL2121: System.Reflection.Emit.TypeBuilderImpl.CheckInterfaces(Type[]): Unused 'UnconditionalSuppressMessageAttribute' for warning 'IL2075'. Consider removing the unused warning suppression. [D:\a\_work\1\s\src\libraries\sfx.proj]

Have you seen these?

No, never seen those and removing those suppressions locally causing still build failure:

...\src\System\Reflection\Emit\TypeBuilderImpl.cs(184,49): error IL2075: 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicMethods', 'DynamicallyAccessedMemberTypes.NonPublicMethods' in call to 'System.Type.GetMethods(BindingFlags)'. The return value of method 'System.Collections.IEnumerator.Current.get' does not have matching annotations.
 The source value must declare at least the same requirements as those declared on the target location it is assigned to.

[buyaa-n]

Is there something related to generics that's not yet implemented maybe?

No generics should have covered completely, no known issue (yet), wonder how that happen, more logs could be helpful

[stephentoub]

@sbomer, can you help @buyaa-n with these illinker warnings?

[stephentoub]

I opened #96469 for the span issue.

[buyaa-n]

No, never seen those warnings

Now I do see the warnings with your branch, but weirdly removing those suppressions reintroduces the IL2075 warning back (not the IL2072)

...\src\System\Reflection\Emit\TypeBuilderImpl.cs(184,49): error IL2075: 'this' argument does not satisfy 'DynamicallyAcc
essedMemberTypes.PublicMethods', 'DynamicallyAccessedMemberTypes.NonPublicMethods' in call to 'System.Type.GetMethods(BindingFlags)'. The return value of method 'System.Col
lections.IEnumerator.Current.get' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location
it is assigned to.

I opened #96469 for the span issue.

Thanks, I will fix it ASAP

[stephentoub]

@sbomer investigated the linker issue and narrowed it down to #96646. He's working on a fix.

[stephentoub]

@sbomer
Fix IL2121 warnings

Thanks.

[stephentoub]

@buyaa-n, can you take another look?

[buyaa-n]

Looks great to me, thanks for using new AssemblyBuilder implementation.