diff --git a/.gitattributes b/.gitattributes
index c75b35afcb..1f0674029e 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -15271,6 +15271,8 @@ tests/webtbs/tw30936.pp svneol=native#text/pascal
 tests/webtbs/tw30936a.pp svneol=native#text/pascal
 tests/webtbs/tw30936b.pp svneol=native#text/pascal
 tests/webtbs/tw30936c.pp svneol=native#text/pascal
+tests/webtbs/tw30939a.pp svneol=native#text/pascal
+tests/webtbs/tw30939b.pp svneol=native#text/pascal
 tests/webtbs/tw30948.pp svneol=native#text/plain
 tests/webtbs/tw30978.pp svneol=native#text/pascal
 tests/webtbs/tw30978a.pp svneol=native#text/pascal
diff --git a/compiler/pdecsub.pas b/compiler/pdecsub.pas
index 8f5609a1fa..f4a5fed790 100644
--- a/compiler/pdecsub.pas
+++ b/compiler/pdecsub.pas
@@ -771,11 +771,12 @@ implementation
             error : boolean;
             genname,
             ugenname : tidstring;
+            module : tmodule;
           begin
             result:=false;
             if not assigned(genericparams) then
               exit;
-            specializename:='';
+            specializename:='$';
             prettyname:='';
             error:=false;
             for i:=0 to genericparams.count-1 do
@@ -794,7 +795,10 @@ implementation
                     error:=true;
                     continue;
                   end;
-                specializename:=specializename+'$'+ttypesym(typesrsym).typedef.fulltypename;
+                module:=find_module_from_symtable(ttypesym(typesrsym).typedef.owner);
+                if not assigned(module) then
+                  internalerror(2016112803);
+                specializename:=specializename+'_$'+hexstr(module.moduleid,8)+'$$'+ttypesym(typesrsym).typedef.unique_id_str;
                 if i>0 then
                   prettyname:=prettyname+',';
                 prettyname:=prettyname+ttypesym(typesrsym).prettyname;
diff --git a/compiler/pgenutil.pas b/compiler/pgenutil.pas
index 8225bd4959..9ddc3415a7 100644
--- a/compiler/pgenutil.pas
+++ b/compiler/pgenutil.pas
@@ -295,6 +295,7 @@ uses
         tmpparampos : tfileposinfo;
         namepart : string;
         prettynamepart : ansistring;
+        module : tmodule;
       begin
         result:=true;
         if genericdeflist=nil then
@@ -310,8 +311,12 @@ uses
         if assigned(parsedtype) then
           begin
             genericdeflist.Add(parsedtype);
-            specializename:='$'+parsedtype.fulltypename;
-            prettyname:=parsedtype.typesym.prettyname;
+            module:=find_module_from_symtable(parsedtype.owner);
+            if not assigned(module) then
+              internalerror(2016112801);
+            namepart:='_$'+hexstr(module.moduleid,8)+'$$'+parsedtype.unique_id_str;
+            specializename:='$'+namepart;
+            prettyname:=parsedtype.fullownerhierarchyname(true)+parsedtype.typesym.prettyname;
             if assigned(poslist) then
               begin
                 New(parampos);
@@ -321,7 +326,7 @@ uses
           end
         else
           begin
-            specializename:='';
+            specializename:='$';
             prettyname:='';
           end;
         while not (token in [_GT,_RSHARPBRACKET]) do
@@ -353,22 +358,23 @@ uses
                     else if (typeparam.resultdef.typ<>errordef) then
                       begin
                         genericdeflist.Add(typeparam.resultdef);
+                        module:=find_module_from_symtable(typeparam.resultdef.owner);
+                        if not assigned(module) then
+                          internalerror(2016112802);
+                        namepart:='_$'+hexstr(module.moduleid,8)+'$$'+typeparam.resultdef.unique_id_str;
                         { we use the full name of the type to uniquely identify it }
                         if (symtablestack.top.symtabletype=parasymtable) and
                             (symtablestack.top.defowner.typ=procdef) and
                             (typeparam.resultdef.owner=symtablestack.top) then
                           begin
                             { special handling for specializations inside generic function declarations }
-                            namepart:=tdef(symtablestack.top.defowner).unique_id_str;
-                            namepart:='genproc'+namepart+'_'+tdef(symtablestack.top.defowner).fullownerhierarchyname(false)+'_'+tprocdef(symtablestack.top.defowner).procsym.realname+'_'+typeparam.resultdef.typename;
-                            prettynamepart:=tdef(symtablestack.top.defowner).fullownerhierarchyname(false)+tprocdef(symtablestack.top.defowner).procsym.prettyname;
+                            prettynamepart:=tdef(symtablestack.top.defowner).fullownerhierarchyname(true)+tprocdef(symtablestack.top.defowner).procsym.prettyname;
                           end
                         else
                           begin
-                            namepart:=typeparam.resultdef.fulltypename;
-                            prettynamepart:=typeparam.resultdef.fullownerhierarchyname(false);
+                            prettynamepart:=typeparam.resultdef.fullownerhierarchyname(true);
                           end;
-                        specializename:=specializename+'$'+namepart;
+                        specializename:=specializename+namepart;
                         if not first then
                           prettyname:=prettyname+',';
                         prettyname:=prettyname+prettynamepart+typeparam.resultdef.typesym.prettyname;
diff --git a/tests/webtbs/tw30939a.pp b/tests/webtbs/tw30939a.pp
new file mode 100644
index 0000000000..a65b23c654
--- /dev/null
+++ b/tests/webtbs/tw30939a.pp
@@ -0,0 +1,23 @@
+{ %NORUN }
+
+program tw30939a;
+
+{$MODESWITCH result}
+
+Type
+  generic TGData<T> = record
+    b: T
+  end;
+
+  generic TGWrapper<T> = record
+    a: specialize TGData<T>
+  end;
+
+generic Function DoSomething<T>: specialize TGWrapper<T>;
+  Begin
+    result.a.b := default(T)
+  End;
+
+Begin
+  specialize DoSomething<LongInt>;
+End.
diff --git a/tests/webtbs/tw30939b.pp b/tests/webtbs/tw30939b.pp
new file mode 100644
index 0000000000..c4d84df789
--- /dev/null
+++ b/tests/webtbs/tw30939b.pp
@@ -0,0 +1,23 @@
+{ %NORUN }
+
+program tw30939a;
+
+{$MODE delphi}
+
+Type
+  TGData<T> = record
+    b: T
+  end;
+
+  TGWrapper<T> = record
+    a: TGData<T>
+  end;
+
+Function DoSomething<T>: TGWrapper<T>;
+  Begin
+    result.a.b := default(T)
+  End;
+
+Begin
+  DoSomething<LongInt>;
+End.