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Message-ID:	<f9a924dd-9131-4034-8622-05d78027ccf1@dronecode.org.uk>
Date:	Fri, 23 May 2025 14:40:45 +0100
MIME-Version:	1.0
User-Agent:	Mozilla Thunderbird
Subject:	Re: gcc links to libcmain when generating a dll
To:	skidmarks <home AT slipbits DOT com>
References:	<e07d3263-f629-4276-b7a8-d977b092d24f AT slipbits DOT com>
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From:	Jon Turney via Cygwin <cygwin AT cygwin DOT com>
Reply-To:	Jon Turney <jon DOT turney AT dronecode DOT org DOT uk>
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On 23/05/2025 14:30, skidmarks via Cygwin wrote:
[...]
> Thanks!
> 
>> g++ -shared -flinker-output=dyn -o slip.dll *.o
> 
> ran with not errors.
> 
> Is there any documentation available on cygwin specific issues?
> This seems like a question that I should be able to answer on my
> own.

Indeed. We do ask people to read the FAQ before posting, and:

https://cygwin.com/faq.html#faq.programming.dll-building

points to

https://cygwin.com/cygwin-ug-net/dll.html

which is in need of updating, but mentions that you should use '-shared'.

But this isn't actually a Cygwin specific question. '-shared' is 
actually the right flag to use everywhere.

 > One residual question that a cygwin specific manual may answer> is 
why libcmain.a was included at all.

Because the linker thinks you are making an executable, which has to 
have a main function.

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