[llvm] [flang][runtime] OPEN(existingUnit,POSITION=) (PR #153688)

[via llvm-commits]

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@@ -197,6 +197,10 @@ class ExternalFileUnit : public ConnectionState,
 
   RT_API_ATTRS int GetAsynchronousId(IoErrorHandler &);
   RT_API_ATTRS bool Wait(int);
+  RT_API_ATTRS Position InquirePosition() const {
+    return OpenFile::InquirePosition(
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dpalermo wrote:

The hostdevice build of flang-rt fails after this change with "error: call to non-static member function without an object argument"
This can be fixed by making a couple small changes:
- OpenFile at line 201 in unit.h should be OpenFileClass
- PseudoOpenFile::InquirePosition() needs to accept FileOffset as a parameter (unit.h & pseudo-unit.cpp)

https://github.com/llvm/llvm-project/pull/153688