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Date: Mon, 01 Sep 2008 19:53:13 -0700
From: Brian Dessent <brian AT dessent DOT net>
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To: "John E. / TDM" <tdragon AT tdragon DOT net>
CC: cygwin AT cygwin DOT com, MinGW Users List <mingw-users AT lists DOT sourceforge DOT net>
Subject: Re: Import library for symbols decl. without dllimport
References: <48BC9E64 DOT 3040701 AT tdragon DOT net>
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"John E. / TDM" wrote:

> This of course works fine, but it's sub-optimal; I would like for the
> message not to be displayed at all, and I imagine that the auto-import
> machinery shouldn't even need to be activated if the import library for
> the libstdc++ DLL is properly designed. Also, hiding the message with
> --enable-auto-import would also hide similar messages from other
> libraries that I *would* want to see.

That's just not how it works for data imports.  For functions yes, but
not for data imports.  You either use auto-import or you
__declspec(dllimport).  It works for functions because the call can go
through a thunk stub.  But for data variables not marked
__declspec(dllimport), there's no indirection; the only way to add the
required indirection (to make the reference to a symbol in another
module whose address isn't known until runtime) is to trick the
operating system loader into modifying the text section at runtime which
is what auto-import does.  There's no way to simulate this with just an
import library as is possible with function thunks.

Brian

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