Re: [Devil-linux-develop] Suggestion for better compiling.

[Heiko Z. <he...@zu...>]

John Kiss wrote:
> 	The kernel is only being compiled for different CPU's, the applications
> are being compiled for 486.
> 
> 	Reason, the tool chain in the LFS system was built for 486 compilation
> and this will be the default -march. To fix this all build scripts will
> have to add to the gcc options a -march=<CPU>. Adding this would be
> easier during ./configure. eg.  CFLAGS= -march=686; ./configure
> <options>.  And of course it would be very nice if the 686 came from a
> shell variable set by the DL config file.


The build system includes the build of it's own gcc. When I check the 
build/tmp/gcc-build directory, I'll see a folder i686-pc-linux-gnu . I 
would expect that *this* gcc is for i686 and compiles everything which 
isn't specified differently for i686.
Long sentence short: the default -march should be (in this case) 686, 
correct?

> 	Now I could still be wrong about this, and someone coming back and
> calling me a moron ;-), but one thing that could be happening is an
> environment variable could be set that sets the default -march for
> gcc??? Maybe Heiko would know the answer to this? But in all the gnu
> toolchains that I've built I've never seen documented that the default
> arch can be controled by an enviornment variable, but the gcc manual is
> pretty thick.

We could define CFLAGS as an environment variable, but some programs 
just don't care about it.


> 	Now a comment that could make this entire discussion mute is compiling
> the kernel from a 486 to a 686 makes a huge difference on the system.
> But what are you really gaining by changing the applications from a 486
> to 686 compiles??? 

I agree with Bruce, just the Kernel is not enough.

cya
   Heiko