Go backward to Cross Runtime.
Go up to Cross-Compiler.

Actually Building the Cross-Compiler

   Now you can proceed just as for compiling a single-machine compiler
through the step of building stage 1.  If you have not provided some
sort of `libgcc1.a', then compilation will give up at the point where
it needs that file, printing a suitable error message.  If you do
provide `libgcc1.a', then building the compiler will automatically
compile and link a test program called `libgcc1-test'; if you get
errors in the linking, it means that not all of the necessary routines
in `libgcc1.a' are available.

   You must provide the header file `float.h'.  One way to do this is
to compile `enquire' and run it on your target machine.  The job of
`enquire' is to run on the target machine and figure out by experiment
the nature of its floating point representation.  `enquire' records its
findings in the header file `float.h'.  If you can't produce this file
by running `enquire' on the target machine, then you will need to come
up with a suitable `float.h' in some other way (or else, avoid using it
in your programs).

   Do not try to build stage 2 for a cross-compiler.  It doesn't work to
rebuild GNU CC as a cross-compiler using the cross-compiler, because
that would produce a program that runs on the target machine, not on the
host.  For example, if you compile a 386-to-68030 cross-compiler with
itself, the result will not be right either for the 386 (because it was
compiled into 68030 code) or for the 68030 (because it was configured
for a 386 as the host).  If you want to compile GNU CC into 68030 code,
whether you compile it on a 68030 or with a cross-compiler on a 386, you
must specify a 68030 as the host when you configure it.

   To install the cross-compiler, use `make install', as usual.