mk: add clang toolchain

Add support for clang by adding a toolchain folder for it with the
appropriate files.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Tested-by: Zhaochen Zhan <zhaochen.zhan@intel.com>
[Thomas: CC from command line overrides HOSTCC]
Acked-by: Thomas Monjalon <thomas.monjalon@6wind.com>

mk/toolchain/clang/rte.toolchain-compat.mk

@@ -0,0 +1,43 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+#   All rights reserved.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of Intel Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#
+# CPUID-related options
+#
+# This was added to support compiler versions which might not support all the
+# flags we need
+#
+
+# find out CLANG version
+
+CLANG_MAJOR_VERSION = $(shell $(CC) -dumpversion | cut -f1 -d.)
+
+CLANG_MINOR_VERSION = $(shell $(CC) -dumpversion | cut -f2 -d.)

mk/toolchain/clang/rte.vars.mk

@@ -0,0 +1,79 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+#   All rights reserved.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of Intel Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#
+# toolchain:
+#
+#   - define CC, LD, AR, AS, ... (overriden by cmdline value)
+#   - define TOOLCHAIN_CFLAGS variable (overriden by cmdline value)
+#   - define TOOLCHAIN_LDFLAGS variable (overriden by cmdline value)
+#   - define TOOLCHAIN_ASFLAGS variable (overriden by cmdline value)
+#
+
+ifeq ($(KERNELRELEASE),)
+CC        = $(CROSS)clang
+else
+CC        = $(CROSS)gcc
+endif
+CPP       = $(CROSS)cpp
+# for now, we don't use as but nasm.
+# AS      = $(CROSS)as
+AS        = nasm
+AR        = $(CROSS)ar
+LD        = $(CROSS)ld
+OBJCOPY   = $(CROSS)objcopy
+OBJDUMP   = $(CROSS)objdump
+STRIP     = $(CROSS)strip
+READELF   = $(CROSS)readelf
+GCOV      = $(CROSS)gcov
+
+ifeq ("$(origin CC)", "command line")
+HOSTCC    = $(CC)
+else
+HOSTCC    = clang
+endif
+HOSTAS    = as
+
+TOOLCHAIN_ASFLAGS =
+TOOLCHAIN_CFLAGS =
+TOOLCHAIN_LDFLAGS =
+
+WERROR_FLAGS := -W -Wall -Werror -Wstrict-prototypes -Wmissing-prototypes
+WERROR_FLAGS += -Wmissing-declarations -Wold-style-definition -Wpointer-arith
+WERROR_FLAGS += -Wnested-externs -Wcast-qual
+WERROR_FLAGS += -Wformat-nonliteral -Wformat-security
+WERROR_FLAGS += -Wundef -Wwrite-strings
+
+# process cpu flags
+include $(RTE_SDK)/mk/toolchain/$(RTE_TOOLCHAIN)/rte.toolchain-compat.mk
+
+export CC AS AR LD OBJCOPY OBJDUMP STRIP READELF
+export TOOLCHAIN_CFLAGS TOOLCHAIN_LDFLAGS TOOLCHAIN_ASFLAGS

mk/toolchain/gcc/rte.vars.mk

@@ -37,8 +37,6 @@
 #   - define TOOLCHAIN_LDFLAGS variable (overriden by cmdline value)
 #   - define TOOLCHAIN_ASFLAGS variable (overriden by cmdline value)
 #
-# examples for RTE_TOOLCHAIN: gcc, icc
-#
 
 CC        = $(CROSS)gcc
 CPP       = $(CROSS)cpp

mk/toolchain/icc/rte.vars.mk

@@ -37,8 +37,6 @@
 #   - define TOOLCHAIN_LDFLAGS variable (overriden by cmdline value)
 #   - define TOOLCHAIN_ASFLAGS variable (overriden by cmdline value)
 #
-# examples for RTE_TOOLCHAIN: gcc, icc
-#
 
 # Warning: we do not use CROSS environment variable as icc is mainly a
 # x86->x86 compiler