Enable simulator on gdb

[Mike Frysinger]

On 29 Jul 2021 09:49, Andrew Burgess wrote:
> * 任建军 via Gdb <gdb@sourceware.org> [2021-07-16 11:52:33 +0800]:
> 
> >    I have a complie question, An help me answer it? 
> >    I use binutils-gdb source code to build gdb for aarch64，the version is “gdb-9.2-release”,   and complie command line is "./configure --target=aarch64 --enable-sim".
> >    Compile is completed, but when i enter gdb and type command "target sim"  , gdb said  "Undefined target command: "sim": ..." ,  am i missed someting when i complie gdb? 
> 
> The problem is that in gdb/configure.tgt there is no link to the
> compiled simulator.  The patch below adds this link for aarch64-elf
> targets.
> 
> I believe the reason for this is that the aarch64 simulator is
> considered deprecated in favour of using QEMU.  Or it could just be an
> oversight that this link is missing.

while i love QEMU, i'm not sure it should be relevant wrt decisions about the
GNU sim and its integration in places.

> Either way, this should get it working for you.
> 
> --- a/gdb/configure.tgt
> +++ b/gdb/configure.tgt
> @@ -117,6 +117,7 @@ case "${targ}" in
>  aarch64*-*-elf | aarch64*-*-rtems*)
>  	# Target: AArch64 embedded system
>  	gdb_target_obs="aarch64-newlib-tdep.o"
> +	gdb_sim=../sim/arm/libsim.a

guessing you meant aarch64 there and not arm ?
-mike