[Buildroot] [PATCH 1/3] Move the host-pkgconf dependency from host-cmake to pkg-cmake

[Luca Ceresoli]

In 3d475ee0ba4d6eea6aca25594cfe5bb153ac804f a dependency on
host-pkgconf was added to host-cmake. It is a workaround to fix build
failures for packages that use pkgconf through a cmake module, but do
not depend on host-pkgconf as they should.

Since it is the package that needs host-pkgconf and not host-cmake
itself, move the dependency to the proper place, in pkg-cmake.mk.

Also copy the explanation on the mentioned commit as a comment in
order to clarify why we do this.

Signed-off-by: Luca Ceresoli <luca at lucaceresoli.net>
Cc: Samuel Martin <s.martin49 at gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Cc: Davide Viti <zinosat at tiscali.it>
Cc: Arnout Vandecappelle <arnout at mind.be>

---

This is done as a preliminary cleanup step for the following patch
that allows to skip building host-cmake in some cases. The dependency
where it is now would be missed when we skip building host-cmake, so I
moved it where it will be catched in all cases. Without the following
patch this can be considered just a cleanup without any visible
effect.
---
 package/cmake/cmake.mk | 2 +-
 package/pkg-cmake.mk   | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/package/cmake/cmake.mk b/package/cmake/cmake.mk
index a776b14..33fb4aa 100644
--- a/package/cmake/cmake.mk
+++ b/package/cmake/cmake.mk
@@ -10,7 +10,7 @@ CMAKE_SITE = https://cmake.org/files/v$(CMAKE_VERSION_MAJOR)
 CMAKE_LICENSE = BSD-3c
 CMAKE_LICENSE_FILES = Copyright.txt
 
-HOST_CMAKE_DEPENDENCIES = host-pkgconf
+HOST_CMAKE_DEPENDENCIES =
 CMAKE_DEPENDENCIES = zlib jsoncpp libcurl libarchive expat bzip2 xz
 
 CMAKE_CONF_OPTS = \
diff --git a/package/pkg-cmake.mk b/package/pkg-cmake.mk
index 81dcfcc..8d7d265 100644
--- a/package/pkg-cmake.mk
+++ b/package/pkg-cmake.mk
@@ -149,6 +149,10 @@ $(2)_DEPENDENCIES ?= $$(filter-out host-skeleton host-toolchain $(1),\
 	$$(patsubst host-host-%,host-%,$$(addprefix host-,$$($(3)_DEPENDENCIES))))
 endif
 
+# Since some CMake modules (even upstream ones) use pgk_check_modules
+# primitives to find {C,LD}FLAGS, add it to the dependency list.
+$(2)_DEPENDENCIES += host-pkgconf
+
 $(2)_DEPENDENCIES += host-cmake
 
 #
-- 
2.7.4