package/python-brotli: fix build failure due to gcc bug 68485

The python-brotli package exhibits gcc bug 68485 when built for the
Microblaze architecture with optimization enabled, which causes a build
failure.

As done for other packages in Buildroot work around this gcc bug by
setting optimization to -O0 if BR2_TOOLCHAIN_HAS_GCC_BUG_68485=y.

Fixes:

http://autobuild.buildroot.net/results/24b/24b23175ab27615fb377bb4d5f6c656dccf10a86/

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/python-brotli/python-brotli.mk

@@ -11,6 +11,14 @@ PYTHON_BROTLI_SETUP_TYPE = setuptools
 PYTHON_BROTLI_LICENSE = MIT
 PYTHON_BROTLI_LICENSE_FILES = LICENSE
 
+PYTHON_BROTLI_CFLAGS = $(TARGET_CFLAGS)
+
+ifeq ($(BR2_TOOLCHAIN_HAS_GCC_BUG_68485),y)
+PYTHON_BROTLI_CFLAGS += -O0
+endif
+
+PYTHON_BROTLI_ENV = CFLAGS="$(PYTHON_BROTLI_CFLAGS)"
+
 define PYTHON_BROTLI_EXTRACT_CMDS
 	$(UNZIP) -d $(@D) $(PYTHON_BROTLI_DL_DIR)/$(PYTHON_BROTLI_SOURCE)
 	mv $(@D)/Brotli-$(PYTHON_BROTLI_VERSION)/* $(@D)