[Buildroot] [PATCH v2 1/1] qemu: add support for python3

[Adam Duskett]

qemu 2.12.0 now supports building against python3.
see: https://wiki.qemu.org/ChangeLog/2.12#Build_Dependencies

Signed-off-by: Adam Duskett <aduskett at gmail.com>
---
Changes v1 -> v2:
  - Split the python version check into two seperate checks for
    readability, one for the target, one for the host.
  - Fix location of the python version check for target and host.

 package/qemu/qemu.mk | 27 ++++++++++++++++++++++-----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/package/qemu/qemu.mk b/package/qemu/qemu.mk
index afb2aa92f6..6dd9ce4a62 100644
--- a/package/qemu/qemu.mk
+++ b/package/qemu/qemu.mk
@@ -16,7 +16,7 @@ QEMU_LICENSE_FILES = COPYING COPYING.LIB
 #-------------------------------------------------------------
 # Target-qemu
 
-QEMU_DEPENDENCIES = host-pkgconf host-python libglib2 zlib pixman
+QEMU_DEPENDENCIES = host-pkgconf libglib2 zlib pixman
 
 # Need the LIBS variable because librt and libm are
 # not automatically pulled. :-(
@@ -25,9 +25,19 @@ QEMU_LIBS = -lrt -lm
 QEMU_OPTS =
 
 QEMU_VARS = \
-	LIBTOOL=$(HOST_DIR)/bin/libtool \
-	PYTHON=$(HOST_DIR)/bin/python2 \
+	LIBTOOL=$(HOST_DIR)/bin/libtool
+
+ifeq ($(BR2_PACKAGE_PYTHON3),y)
+QEMU_DEPENDENCIES += host-python3
+QEMU_VARS += \
+	PYTHON=$(HOST_DIR)/bin/python3 \
+	PYTHONPATH=$(TARGET_DIR)/usr/lib/python$(PYTHON3_VERSION_MAJOR)/site-packages
+else
+QEMU_DEPENDENCIES += host-python
+QEMU_VARS += \
+	PYTHON=$(HOST_DIR)/bin/python \
 	PYTHONPATH=$(TARGET_DIR)/usr/lib/python$(PYTHON_VERSION_MAJOR)/site-packages
+endif
 
 # If we want to specify only a subset of targets, we must still enable all
 # of them, so that QEMU properly builds its list of default targets, from
@@ -150,7 +160,7 @@ $(eval $(generic-package))
 #-------------------------------------------------------------
 # Host-qemu
 
-HOST_QEMU_DEPENDENCIES = host-pkgconf host-python host-zlib host-libglib2 host-pixman
+HOST_QEMU_DEPENDENCIES = host-pkgconf host-zlib host-libglib2 host-pixman
 
 #       BR ARCH         qemu
 #       -------         ----
@@ -263,12 +273,19 @@ define HOST_QEMU_CONFIGURE_CMDS
 		--interp-prefix=$(STAGING_DIR) \
 		--cc="$(HOSTCC)" \
 		--host-cc="$(HOSTCC)" \
-		--python=$(HOST_DIR)/bin/python2 \
 		--extra-cflags="$(HOST_CFLAGS)" \
 		--extra-ldflags="$(HOST_LDFLAGS)" \
 		$(HOST_QEMU_OPTS)
 endef
 
+ifeq ($(BR2_PACKAGE_PYTHON3),y)
+HOST_QEMU_DEPENDENCIES += host-python3
+HOST_QEMU_CONFIGURE_CMDS += --python=$(HOST_DIR)/bin/python3
+else
+HOST_QEMU_DEPENDENCIES += host-python
+HOST_QEMU_CONFIGURE_CMDS += --python=$(HOST_DIR)/bin/python2
+endif
+
 define HOST_QEMU_BUILD_CMDS
 	$(HOST_MAKE_ENV) $(MAKE) -C $(@D)
 endef
-- 
2.17.1