Changeset 955a9ba7 in rtems for cpukit/score/cpu/mips/Makefile.am

Patch rtems-rc-19991123-rc-2.diff from Ralf Corsepius
<corsepiu@…> which implements automake support for some
score/cpu/<RTEMS_CPU> subdirectories and fixes a few minor configuration
bugs.

To apply:

rm -rf c/src/exec/score/cpu/a29k/wrap
rm -rf c/src/exec/score/cpu/hppa1.1/wrap
rm -rf c/src/exec/score/cpu/i386/wrap
rm -rf c/src/exec/score/cpu/mips64orion/wrap
rm -rf c/src/exec/score/cpu/no_cpu/wrap
patch -p1 < rtems-rc-19991123-rc-2.diff.gz

Notes:

• I don't see a possiblity to convert the powerpc subdirectory in its current layout to automake the time being.

• Besides the fact that this subdirectory is not in single-tree building layout, the actual showstopper is the ifeq $(RTEMS_CPU_MODEL),mpc750) gmake-conditional in powerpc/Makefile.in, which automake (correctly) refuses to handle.

• The problem is *not* specific to the powerpc. Other CPUs basically have similar problems (SH:sh7032 vs sh7045, SPARC: erc32.h in score/cpu/sparc), but have been lucky to get around real issues (cf. configuration files below score/cpu/sh/).

• From a configuration focused POV this problem boils down to a file/subdirectory selection problem:

ppc: 1 or others
sh: 1 out of 2
sparc: 1 out of 1

Automake's means to implement such behavior is using conditionals to be
evaluated at configuration-time. The old configuration scheme however
used make-time conditionals. The SH port was lucky to get around this
issue because it applies a selection from a limited set of possible
selections, the powerpc however applies a selection from an unlimited
set, based on data not being available at configuration time.

• Currently I only see two general solutions:

1) make RTEMS_CPU_MODEL available at configuration time, ie. replace

make-time configuration by configuration-time configuration

2) Perform the selection at build-time, i.e. always install all files,

but use #ifdef #else #endif in source files. This is what the m68k has
exploited at other locations inside of the source-tree.

=> This directory is the last one remaining not using automake below the

whole exec/ hierarchy.