arm-elf MULTILIBS_DEFAULT

[Ralf Corsepius]

Hi,

I am trying to extend the multilib being used for arm-rtems (more less
is identical to arm-*-elf).

To do so, I introduced a gcc/config/arm/t-rtems containing this:
MULTILIB_OPTIONS     = marm/mthumb msoft-float/mhard-float
MULTILIB_DIRNAMES    = arm thumb soft fpu
MULTILIB_EXCEPTIONS  =
MULTILIB_MATCHES =

Resulting into this multilibs:
# /opt/rtems/bin/arm-rtems-gcc -print-multi-lib
.;
thumb;@mthumb
fpu;@mhard-float
thumb/fpu;@mthumb@mhard-float

[Note this assumes '.' to imply -msoft-float -marm]

However, when trying to link an arbitrary fp-application using
-msoft-float I end up with the linker complaining about FP-stuff:

# /opt/rtems/bin/arm-rtems-gcc -msoft-float tmp.c
/opt/rtems/lib/gcc-lib/arm-rtems/3.2.2/../../../../arm-rtems/bin/ld:
ERROR: /opt/rtems/lib/gcc-lib/arm-rtems/3.2.2/libgcc.a(_df_to_sf.o) uses
hardware FP, whereas a.out uses software FP
..

If I understand correctly, this indicates that the arm-elf default flags
do not match with arm-elf's MULTILIB_DEFAULTS (from arm-elf.h).

What am I missing? 

TIA,
	Ralf