How do you represent a host gcc and a cross gcc in lcitool?

["Alex Bennée" <alex.bennee@linaro.org>]

Hi,

While trying to convert the debian-riscv64-cross docker container to an
lcitool based one I ran into a problem building QEMU. The configure step
fails because despite cross compiling we still need a host compiler to
build the hexagon codegen tooling.

After scratching my head for a while I discovered we did have host GCC's
in our cross images despite there being no explicit request for them in
the docker description. It turned out that the gcovr requirement pulled
in lcov which itself had a dependency on gcc. However this is a bug:

  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=987818

which has been fixed in bookworm (and of course sid which is the only
way we can get a riscv64 build of QEMU at the moment). Hence my hacky
attempts to get gcc via side effect of another package failed.

Hence the question in $SUBJECT. I tried to add a mapping to lcitool for
a pseudo hostgcc package:

+  hostgcc:
+    default: gcc
+    pkg:
+    MacOS:
+    cross-policy-default: skip

however this didn't work. Do we need a new mechanism for this or am I
missing a way to do this?

RiscV guys,

It's clear that relying on Debian Sid for the QEMU cross build for RiscV
is pretty flakey. Are you guys aware of any other distros that better
support cross compiling to a riscv64 target or is Debian still the best
bet? Could you be persuaded to build a binary docker image with the
cross compilers and libraries required for a decent cross build as an
alternative?

Thanks,

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro