initial buildroot for linux 5.15

package/protobuf/Config.in

@@ -0,0 +1,46 @@
+# See src/google/protobuf/stubs/platform_macros.h for supported archs.
+#
+# On PowerPC, the __atomic_*() built-ins for 1-byte, 2-byte and 4-byte
+# types are available built-in. However, the __atomic_*() built-ins for
+# 8-byte types is implemented via libatomic, so only available since gcc
+# 4.8.
+#
+# In Buildroot, to simplify things, we've decided to simply require gcc
+# 4.8 as soon as the architectures has at least one __atomic_*() built-in
+# variant that requires libatomic.
+#
+# Since protobuf most likely only uses the 1, 2 and 4-byte variants, it
+# *could* technically build with gcc 4.7. This is probably not a big deal,
+# and we can live with requiring gcc 4.8 on PowerPC to build protobuf.
+#
+# host-protobuf only builds on certain architectures
+config BR2_PACKAGE_PROTOBUF_ARCH_SUPPORTS
+	bool
+	default y if BR2_arm
+	default y if BR2_i386
+	default y if BR2_mipsel
+	default y if BR2_x86_64
+	default y if BR2_sparc64
+	default y if BR2_TOOLCHAIN_HAS_ATOMIC
+	depends on BR2_HOSTARCH = "x86_64" || BR2_HOSTARCH = "x86"
+	depends on BR2_USE_MMU # fork()
+	depends on !BR2_TOOLCHAIN_HAS_BINUTILS_BUG_21464
+
+config BR2_PACKAGE_PROTOBUF
+	bool "protobuf"
+	depends on BR2_INSTALL_LIBSTDCPP
+	depends on BR2_TOOLCHAIN_HAS_THREADS
+	depends on BR2_PACKAGE_PROTOBUF_ARCH_SUPPORTS
+	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_4_8 # C++11
+	depends on !BR2_STATIC_LIBS
+	help
+	  Protocol buffers are Google's language-neutral,
+	  platform-neutral, extensible mechanism for serializing
+	  structured data.
+
+	  https://developers.google.com/protocol-buffers
+
+comment "protobuf needs a toolchain w/ C++, threads, dynamic library, gcc >= 4.8"
+	depends on !BR2_INSTALL_LIBSTDCPP || !BR2_TOOLCHAIN_HAS_THREADS \
+		|| BR2_STATIC_LIBS || !BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
+	depends on BR2_PACKAGE_PROTOBUF_ARCH_SUPPORTS

package/protobuf/protobuf.hash

@@ -0,0 +1,3 @@
+# Locally calculated
+sha256  6e5e117324afd944dcf67f36cf329843bc1a92229a8cd9bb573d7a83130fea7d  LICENSE
+sha256  7308590dbb95e77066b99c5674eed855c8257e70658d2af586f4a81ff0eea2b1  protobuf-cpp-3.18.0.tar.gz

package/protobuf/protobuf.mk

@@ -0,0 +1,51 @@
+################################################################################
+#
+# protobuf
+#
+################################################################################
+
+# When bumping this package, make sure to also verify if the
+# python-protobuf package still works and to update its hash,
+# as they share the same version/site variables.
+PROTOBUF_VERSION = 3.18.0
+PROTOBUF_SOURCE = protobuf-cpp-$(PROTOBUF_VERSION).tar.gz
+PROTOBUF_SITE = https://github.com/protocolbuffers/protobuf/releases/download/v$(PROTOBUF_VERSION)
+PROTOBUF_LICENSE = BSD-3-Clause
+PROTOBUF_LICENSE_FILES = LICENSE
+PROTOBUF_CPE_ID_VENDOR = google
+
+# N.B. Need to use host protoc during cross compilation.
+PROTOBUF_DEPENDENCIES = host-protobuf
+PROTOBUF_CONF_OPTS = --with-protoc=$(HOST_DIR)/bin/protoc
+
+PROTOBUF_CXXFLAGS = $(TARGET_CXXFLAGS)
+
+ifeq ($(BR2_TOOLCHAIN_HAS_GCC_BUG_85180),y)
+PROTOBUF_CXXFLAGS += -O0
+endif
+
+ifeq ($(BR2_or1k),y)
+PROTOBUF_CXXFLAGS += -mcmodel=large
+endif
+
+PROTOBUF_CONF_ENV = CXXFLAGS="$(PROTOBUF_CXXFLAGS)"
+
+ifeq ($(BR2_TOOLCHAIN_HAS_LIBATOMIC),y)
+PROTOBUF_CONF_ENV += LIBS=-latomic
+endif
+
+PROTOBUF_INSTALL_STAGING = YES
+
+ifeq ($(BR2_PACKAGE_ZLIB),y)
+PROTOBUF_DEPENDENCIES += zlib
+endif
+
+define PROTOBUF_REMOVE_UNNECESSARY_TARGET_FILES
+	rm -rf $(TARGET_DIR)/usr/bin/protoc
+	rm -rf $(TARGET_DIR)/usr/lib/libprotoc.so*
+endef
+
+PROTOBUF_POST_INSTALL_TARGET_HOOKS += PROTOBUF_REMOVE_UNNECESSARY_TARGET_FILES
+
+$(eval $(autotools-package))
+$(eval $(host-autotools-package))