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Subject: Re: Allegro library would need to be recompiled with -fgnu89-inline ?
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From: Damien Guibouret <damien DOT guibouret AT partition-saving DOT com>
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Date: Sun, 27 Jun 2021 18:07:59 +0200
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Hello,

This is a change in behaviour of GCC-10: last change described in 
https://gcc.gnu.org/gcc-10/changes.html#c

Using -fcommon is certainly not the correct correction (but could be a 
workaround for old programs with a lot of occurence of this problem), 
but adding extern or static depending on if the variable should be 
shared or not is better.

Regards,

Damien

On 27/06/2021 00:20, Paul Dufresne (dufresnep AT zoho DOT com) [via 
djgpp AT delorie DOT com] wrote:
> I now think that adding "external" before declarations in .h is the 
> correct solution.
> If they were not mark static already, it is that the value is expected 
> to be shared (being global).
> The solution is *I now think* to add external, and have the real 
> declaration in a unique place, like in main.c.
>