Building a cross compiler fails due to hardcoding host=target in gcc/Makefile.in

[William ML Leslie]

Greetings,

Please keep me CC'd as I'm not subscribed.

I've been trying to build a cross compilation toolchain (for a new OS)
and ran into a confusing error while building gcc 10.2.0.  While
building libgcc, it fails running libgcc/config.host as it gets passed
my target instead of the actual host.  I traced this back to the root
Makefile.in, for which the `configure-target-libgcc` rule ends with:

    CONFIG_SITE=no-such-file $(SHELL) \
      $$s/$$module_srcdir/configure \
      --srcdir=$${topdir}/$$module_srcdir \
      $(TARGET_CONFIGARGS) --build=${build_alias} --host=${target_alias} \
      --target=${target_alias}  \
      || exit 1

This is probably someone trying to be helpful when building a Canadian
Cross (host == target), however there is already a host_alias variable
defined at the very top of `Makefile.in`.  When using a traditional
cross compiler, the host is equal to the build machine; but the
makefile ignores this case.

Have I missed something, or should I send a patch for this?

Snippet of make output where I hit this:

Checking multilib configuration for libgcc...
mkdir -p -- i386-unknown-capros/libgcc
Configuring in i386-unknown-capros/libgcc
...
checking for target glibc version... 0.0
*** Configuration i386-unknown-capros not supported
Makefile:12629: recipe for target 'configure-target-libgcc' failed
make[1]: *** [configure-target-libgcc] Error 1
make[1]: Leaving directory '/extra/wleslie/xenv2/build/gcc-10.2.0/build-capros'
Makefile:954: recipe for target 'all' failed
make: *** [all] Error 2

-- 
William Leslie

Q: What is your boss's password?
A: "Authentication", clearly

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