Re: [PATCH 3/4] configure: Prefer gmake on darwin

[Eric Blake <eblake@redhat.com>]

On 8/22/20 4:21 PM, Roman Bolshakov wrote:
> New meson/make build requires GNU make 3.82+ but macOS ships 3.81 even
> on Big Sur while homebrew provides GNU make 4.3 as 'gmake' in $PATH.

Does this line up with our development policies on supported platforms? 
Should we be fixing the creation of Makefile.ninja to avoid constructs 
not understood by older GNU make, if that is what is shipped out of the 
box on MacOS as one of our supported platforms?  Or is MacOS on the 
fringe for what counts as supported, where we are okay mandating that 
users must install a separate newer GNU make than what comes by default?

> 
> With the change, 'make' switches over to gmake implicitly.

If gmake ships new enough by default, then this seems like a slick 
trick, although I am not in a position to test it.

> @@ -916,6 +917,27 @@ Darwin)
>     # won't work when we're compiling with gcc as a C compiler.
>     QEMU_CFLAGS="-DOS_OBJECT_USE_OBJC=0 $QEMU_CFLAGS"
>     HOST_VARIANT_DIR="darwin"
> +  cat > GNUmakefile <<'EOF'
> +# This file is auto-generated by configure to implicitly switch from a 'make'
> +# invocation to 'gmake'

Are we going to run into issues with an in-tree build trying to create 
GNUmakefile to switch over to build/, while also creating 
build/GNUmakefile to switch from make to gmake?


-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
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