tools build: Add feature detection for g++

Check if g++ is available. The result will be used by builtin clang and
LLVM support. Since LLVM requires C++11, this feature detector checks
std::move().

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1474874832-134786-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Wang Nan 2016-09-26 07:26:56 +00:00 committed by Arnaldo Carvalho de Melo
parent f61bdc3304
commit 87095f7dde
3 changed files with 25 additions and 2 deletions

View File

@ -7,7 +7,7 @@ endif
feature_check = $(eval $(feature_check_code))
define feature_check_code
feature-$(1) := $(shell $(MAKE) OUTPUT=$(OUTPUT_FEATURES) CFLAGS="$(EXTRA_CFLAGS) $(FEATURE_CHECK_CFLAGS-$(1))" LDFLAGS="$(LDFLAGS) $(FEATURE_CHECK_LDFLAGS-$(1))" -C $(feature_dir) $(OUTPUT_FEATURES)test-$1.bin >/dev/null 2>/dev/null && echo 1 || echo 0)
feature-$(1) := $(shell $(MAKE) OUTPUT=$(OUTPUT_FEATURES) CFLAGS="$(EXTRA_CFLAGS) $(FEATURE_CHECK_CFLAGS-$(1))" CXXFLAGS="$(EXTRA_CXXFLAGS) $(FEATURE_CHECK_CXXFLAGS-$(1))" LDFLAGS="$(LDFLAGS) $(FEATURE_CHECK_LDFLAGS-$(1))" -C $(feature_dir) $(OUTPUT_FEATURES)test-$1.bin >/dev/null 2>/dev/null && echo 1 || echo 0)
endef
feature_set = $(eval $(feature_set_code))

View File

@ -46,11 +46,13 @@ FILES= \
test-lzma.bin \
test-bpf.bin \
test-get_cpuid.bin \
test-sdt.bin
test-sdt.bin \
test-cxx.bin
FILES := $(addprefix $(OUTPUT),$(FILES))
CC := $(CROSS_COMPILE)gcc -MD
CXX := $(CROSS_COMPILE)g++ -MD
PKG_CONFIG := $(CROSS_COMPILE)pkg-config
all: $(FILES)
@ -58,6 +60,9 @@ all: $(FILES)
__BUILD = $(CC) $(CFLAGS) -Wall -Werror -o $@ $(patsubst %.bin,%.c,$(@F)) $(LDFLAGS)
BUILD = $(__BUILD) > $(@:.bin=.make.output) 2>&1
__BUILDXX = $(CXX) $(CXXFLAGS) -Wall -Werror -o $@ $(patsubst %.bin,%.cpp,$(@F)) $(LDFLAGS)
BUILDXX = $(__BUILDXX) > $(@:.bin=.make.output) 2>&1
###############################
$(OUTPUT)test-all.bin:
@ -217,6 +222,9 @@ $(OUTPUT)test-bpf.bin:
$(OUTPUT)test-sdt.bin:
$(BUILD)
$(OUTPUT)test-cxx.bin:
$(BUILDXX) -std=gnu++11
-include $(OUTPUT)*.d
###############################

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@ -0,0 +1,15 @@
#include <iostream>
#include <memory>
static void print_str(std::string s)
{
std::cout << s << std::endl;
}
int main()
{
std::string s("Hello World!");
print_str(std::move(s));
std::cout << "|" << s << "|" << std::endl;
return 0;
}