From: "Matthew Smith" <matt AT the-good-stuff DOT freeserve DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Allegro - link problem with irqwrap.S
Date: Fri, 3 Nov 2000 21:53:40 -0000
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

I just searched the Allegro folder for irq_wrapper_0
and got this

Searching for 'irq_wrapper_0'...
c:\ALLEGWIP\ALLEGRO\src\dos\djirq.c(39):extern void _irq_wrapper_0(),
_irq_wrapper_1(),
c:\ALLEGWIP\ALLEGRO\src\dos\djirq.c(43):     _irq_wrapper_0_end();
c:\ALLEGWIP\ALLEGRO\src\dos\djirq.c(56):   LOCK_FUNCTION(_irq_wrapper_0);
c:\ALLEGWIP\ALLEGRO\src\dos\djirq.c(109):     case 0: addr.offset32 =
(long)_irq_wrapper_0; break;
c:\ALLEGWIP\ALLEGRO\src\dos\wat.c(468):END_OF_STATIC_FUNCTION(irq_wrapper_0)
;
c:\ALLEGWIP\ALLEGRO\src\dos\wat.c(479):   LOCK_FUNCTION(irq_wrapper_0);
c:\ALLEGWIP\ALLEGRO\src\dos\wat.c(488):     case 0: _dos_setvect(num,
irq_wrapper_0); break;
7 occurrence(s) have been found.

which suggests to me the function is defined differently for each compiler.
Are you sure you are including the one you want?