<hr /><i>oehhar added on 2018-02-20 21:50:59 UTC:</i><br />
What I understand from [https://www.w3.org/TR/xmlschema-1/#ct-target_namespace], an abstract type should have:

   *   simpleContent
   *   complexContent

In our case, it is complex content, but saved as simple type.

So this is changed in branch [bug584bfb7727-abstract-type] by commit [6975d0e818].

This results in a complex type definition for tns1:Envelope with the attributes:

<verbatim>
typeInfo client $service tns1:envelope {
    definition {}
    xns tns1
    abstract true
}
</verbatim>

The result is still the same. This does not help and there is more work necessary.

But here is the log of the WSDL parse of envelope type:

<verbatim>
Entering parseComplexType Client serviceInfo 1 domNode053DBE0C tns1 
Complex Type is tns1:Envelope 
	 Abstract type = true 
Complex Type is tns1:Envelope, middle is annotation 
Complex Type is tns1:Envelope, middle is complexContent 
isComplexContent := 1 
Content Type is {extension} 
Calling partList for extension of tns1:Envelope 
Entering partList Client domNode053DBEBC 1 results tns1 -- for extension 
	 base name of extension is {tns1:Geometry} with typeinfo {0 0} 
	 Simple type 
partList for extension of tns1:Envelope is {{}} 
at end of foreach {tns1:Envelope} with {} 
Defining tns1:Envelope as  
Entering ::WS::Utils::ServiceTypeDef Client 1 tns1:Envelope {} tns1 true 
</verbatim>