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Re: PCRE package for consideration



Ronald Landheer-Cieslak wrote:


> I'll apply the patch, test it and report back.
>
> If all this works, I'll also ask mr Hazel to relibtoolize
> and see whether the same thing also works on MinGW (if so,
> consider the ON_WINDOWS crap gone).

Now, let's not be hasty. While my patch *should* enable pcre to build properly on mingw -- assuming your MSYS environment has up-to-date autotools -- it relies on auto-import.

Auto-import works fine on both cygwin and mingw.

However, on mingw there are a few compatibility issues that one should consider. DLLs which rely on auto-import under mingw are NOT compatible with MSVC or BorlandC development -- only the GNU linker understands auto-import. (Just to avoid confusion:

--------------------------
On machine A, you have mingw/MSYS installed, and build

libfoo-0.dll
a mingw DLL which utilizes auto-import. It is created using MSYS/mingw tools.


bar.exe
a mingw app which is created using MSYS/mingw tools. It is linked against libfoo-0.dll.


No problems. bar.exe runs like a champ. You then copy libfoo-0.dll and bar.exe over to machine B. On machine B, you only have MSVC; no mingw tools at all.

You can RUN bar.exe with no problems.

Now, you copy the source code for bar.exe from machine A to machine B -- and try to rebuild the app using MSVC, linking against the already-built libfoo-0.dll.

No can do.  MSVC doesn't understand the dll's export table.
----------------------------

Since the whole point of mingw is an interoperable (but free beer/speech) compiler on windows, the decision to create a "port" of a library using auto-import should be carefully considered.

On cygwin, though, no such worries attest. We're happily independent of MSVC/Borland's linker and don't need to worry about their lack of capability in this regard.

So, while this is a porter/maintainer decision, there are good reasons to keep the "ON_WINDOWS" gobbledy-gook for mingw, IF you wish. (But on cygwin -- go ahead, use auto-import. C'mon in, the water's fine.)

--Chuck


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