to multiple. This lets the stack check extension be installed
at system initialization time and avoids the BSP having to
even know about its existence.
based on the GNU tools. This usually involved correcting the
type of bsp_start(), bsp_cleanup(), adjusting the start code to
call the right start routine (the shared boot_card()), and then
removing code from bsp_start() which was performed in the new
boot_card()/main() path.
Here is the result of my nightly work to get RTEMS_ROOT=$srcdir working
with different shells and relative/absolute paths.
What I did is relatively simple in principle:
Instead of setting RTEMS_ROOT in configure.in and then let configure
substitute @RTEMS_ROOT@ inside the Makefiles, I now let each Makefile
set RTEMS_ROOT from each Makefile's @top_srcdir@ value.
The difference is subtile, but with enormous side effects:
- If RTEMS_ROOT is set in configure, then the same single value will be
propagated to all Makefiles. This breaks using relative paths, as the
relative path to the root of the source tree is used inside of all
subdirectory Makefiles.
- Now each Makefile.in sets RTEMS_ROOT = @top_srcdir@. top_srcdir is
computed individually by configure for each single Makefile.in, hereby
receiving the correct value, no matter if relative or absolute paths are
used.
To get this working, I needed to remove setting RTEMS_ROOT from
target.cfg.in, because this overrides the value of RTEMS_ROOT from each
individual Makefile.
Furthermore, I removed RTEMS_CUSTOM from the Makefiles and replaced all
"include $(RTEMS_CUSTOM)" directives with"include
$(RTEMS_ROOT)/make/custom/$(RTEMS_BSP)". Perhaps you don't like this,
but I think, to have one variable less is clearer and easier to
understand than having several variables refering to the next one.
I enclose a small patch to this mail, which
- fixes the config.h problem (to finally clearify misunderstands)
- removes assignment/subsitution of RTEMS_ROOT from configure.in
- contains a workaround for the application Makefile's RTEMS_ROOT
problem (reported by Eric)
- removes some unused lines from the toplevel Makefile.in
- removes assignment of RTEMS_ROOT from make/target.cfg.in
interpreted at the right point per Eric Norum's discovery:
The problem with the my previous `fix' for adding linker commands
was with the ordering of the options to the linker.
For example, to make a larger heap size, the application Makefile would
CFLAGS_LD = -Wl,--defsym -Wl,HeapSize=0x40000
The command passed to the linker would be :
m68k-rtems-ld .... -T xxx/linkcmds .... --defsym HeapSize=0x40000 .....
This doesn't work because the script in linkcmds inserts a default
value for HeapSize if HeapSize is not defined by the time the linker
looks at the linkcmds script.
The solution seems to be to move the -T linkcmds%s in the bsp_specs
file out of the link specfication and into the lib specification -- a
little unorthodox, perhaps, but it seems to work!
GNU autoconf. This is the first large step in allowing an RTEMS
user to perform a one-tree build (per crossgcc FAQ) including RTEMS
in the build process. With this change RTEMS is configured in
built in the same style as the GNU tools, yet retains the basic
structure of its traditional Makefiles (ala Tony Bennett).
Jiri Gaisler (jgais@wd.estec.esa.nl) deserves (and received)
a big thank you for doing this.
There are still issues to be resolved but as of this commit, all target
which can be built on a linux host have been using a modified version
of the source Jiri submitted. This source was merged and most targets
built in the tree before this commit.
There are some issues which remain to be resolved but they are primarily
related to host OS dependencies, script issues, the use of gawk
for hack_specs, and the dependence on gcc snapshots. These will
be resolved.
