[ipxe-devel] Compiling the current HEAD?

[Michael Brown]

On Tuesday 10 Apr 2012 10:20:09 Robin Smidsrød wrote:
> On 09.04.2012 16:50, Jason Kohles wrote:
> > I'm trying to build the current HEAD so I can check out the new menu
> > stuff, and I've encountered an error that I haven't been able to track
> > down, probably due to the huge number of years it's been since I dealt
> > with assembler..
> > 
> > arch/i386/interface/pcbios/int13.c: In function 'int13_hook':
> > arch/i386/interface/pcbios/int13.c:1466: warning: asm operand 1 probably
> > doesn't match constraints
> > arch/i386/interface/pcbios/int13.c:1466: warning: asm operand 2 probably
> > doesn't match constraints
> > make: *** [bin/int13.o] Error 1
> > 
> > Can anybody tell me what is going on here?  I tried simply suppressing
> > the warning (by compiling this file without -Werror) but then I get an
> > "impossible constraint in 'asm'" for the same line of code, so I'm
> > guessing that means the operands really are wrong..
> 
> I just compiled HEAD on an Ubuntu 10.04 machine using the standard
> toolchain. Are you using old (or quite new) versions of the toolchain?

I've seen this problem before, where gcc sometimes doesn't fully simplify an 
expression down to the compile-time constant that it really is.  Should now be 
fixed:

  http://git.ipxe.org/ipxe.git/commitdiff/3c13d68

Michael