Re: compiling gcc using --with-headers pointing to linux headers

[bgat at open-widgets dot com]

DaveK et al:


>   Nope.  I *believe* (but not having a Linux system to check this up on I
> cannot *promise*) that you've chosen the wrong set of the two sets of Linux
> headers.  The what !?!?!  Yep, I said two sets of Linux headers.  One is 
> part of the kernel source - that looks like the one you've mentioned above
>  - and one is there for the user's compiler - and that's the one you should
> be using.
> 
>   The kernel source headers are very specialized, and designed for the
> compilation of the kernel itself, which obviously enough runs without any
> C library (after all, it provides the actual syscalls that the libc has to
> invoke to perform the functions of things like stdio.)  So they don't define
> all the standard library stuff, and that's why there was no stdlib.h!
> 
>   The user headers OTOH are the straightforward headers that explain the
> C library's contents and datatypes, and it's that which is what Gcc wants
> to know about when it compiles libgcc for the cross target.  I'm not sure
> where they live, but it will be either /include or /usr/include; have a
> look in /usr/include first.  Whereever they turn out to be when you find
> them (a good way would be to look at the output given by gcc -print-search-
> dirs with your native compiler), that is the argument you must give to 
> --with-includes.

Bingo.  There isn't a stdlib.h in the kernel headers--- that header
file is supposed to come from the header files associated with the
target's C runtime library.


b.g.
-- 
Bill Gatliff
bgat@open-widgets.com

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