Commit 067c650c45 ("dtc: Use pkg-config to locate libyaml") added
'pkg-config --libs' to link libyaml installed in a non-standard
location.
yamltree.c includes <yaml.h>, but that commit did not add the search
path for <yaml.h>. If /usr/include/yaml.h does not exist, it fails to
build. A user can explicitly pass HOSTCFLAGS to work around it, but
the policy is not consistent.
There are two ways to deal with libraries in a non-default location.
[1] Use HOSTCFLAGS and HOSTLDFLAGS for additional search paths for
headers and libraries.
They are documented in Documentation/kbuild/kbuild.rst
$ make HOSTCFLAGS='-I <prefix>/include' HOSTLDFLAGS='-L <prefix>/lib'
[2] Use pkg-config
'pkg-config --cflags' for querying the header search path
'pkg-config --libs' for querying the lib and its path
If we go with pkg-config, use [2] consistently. Do not mix up
[1] and [2].
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>