PEVerify: Value class has neither fields nor size parameter

[Kenneth Skovhede]

When I emit a struct that has no fields, only functions, everything seems to work,

but PEVerify gives an error: 

[MD]: Error: Value class has neither fields nor size parameter. [token:0x02000002]

I have been looking for some way to set the "size parameter" but can't find it.

Is there any way I can make the error to go away, besides adding a dummy field?

Regards, Kenneth

[Alex]

Hi Kenneth,

Try setting TypeDef.ClassSize. The default for this property probably
won't work in your case.

Regards,
Alex

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[Kenneth Skovhede]

Thanks, after setting ClassSize = 0 I get:

[MD]: Error: Value class has neither fields nor size parameter. [token:0x02000002]

[MD]: Error: ClassLayout has invalid PackingSize; valid set of values is {1,2,4,...,128} (parent: 0x02000002; PackingSize: 65535). [token:0x00000001]

Setting PackagingSize = 0 removes the second error, but PEVerify still complains about with:

[MD]: Error: Value class has neither fields nor size parameter. [token:0x02000002]

I'm guessing that size=0 is not allowed, even for a struct with no data,

or being handled incorrectly by the Cecil emitter.

My fix is to locally set:

type.ClassSize = type.PackingSize = (short)System.Runtime.InteropServices.Marshal.SizeOf(typeof(IntPtr));

I'm not sure how much overhead this will cause, but presumably this will take up 4/8 bytes of stack space for each call.

Regards, Kenneth

[Gábor Kozár]

As far as I know, the minimum size of an object is 4 bytes (the size of a plain System.Object value). You could try setting it to that value, and see if PEVerify still complains.

2011/7/22 Kenneth Skovhede <ken...@hexad.dk>

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