Libguestfs - Mar 2020 - [nbdkit PATCH] eval: Rebuild hard link if git breaks it

Commit 39b40750dd works if you use 'make clean', but not if you rely
on incremental builds.  Git likes to update files by creating new
inodes, which strands hard links.  We could either use symlinks, or as
done here, add a dependency to force the hard links to be rebuilt as
needed.

Fixes: 45b4877fde
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 plugins/eval/Makefile.am | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/plugins/eval/Makefile.am b/plugins/eval/Makefile.am
index abbe17a0..19de6c0d 100644
--- a/plugins/eval/Makefile.am
+++ b/plugins/eval/Makefile.am
@@ -1,5 +1,5 @@
 # nbdkit
-# Copyright (C) 2017-2019 Red Hat Inc.
+# Copyright (C) 2017-2020 Red Hat Inc.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
@@ -43,7 +43,7 @@ BUILT_SOURCES = \
 	call.c \
 	methods.c \
 	$(NULL)
-$(BUILT_SOURCES):
+$(BUILT_SOURCES): ../sh/call.c ../sh/methods.c
 	ln -f ../sh/$@
 CLEANFILES += $(BUILT_SOURCES)

-- 
2.25.1

On 3/16/20 3:59 PM, Eric Blake wrote:
> Commit 39b40750dd works if you use 'make clean', but not if you
rely
> on incremental builds.  Git likes to update files by creating new
> inodes, which strands hard links.  We could either use symlinks, or as
> done here, add a dependency to force the hard links to be rebuilt as
> needed.
> 
> Fixes: 45b4877fde
> Signed-off-by: Eric Blake <eblake@redhat.com>
> ---
>   plugins/eval/Makefile.am | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
Bummer - this is creating the hard link that I expected, but is still 
letting me fail 'make check' with:

nbdkit: error: cannot open plugin 
'/home/eblake/nbdkit/plugins/eval/.libs/nbdkit-eval-plugin.so': 
/home/eblake/nbdkit/plugins/eval/.libs/nbdkit-eval-plugin.so: undefined 
symbol: sh_get_ready

so I'm trying to figure out what to put in v2


-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org