| Message ID | 1447919161-98539-1-git-send-email-wangnan0@huawei.com |
|---|---|
| State | Superseded |
| Headers | show |
diff --git a/tools/build/Makefile.include b/tools/build/Makefile.include index 4e09ad6..6254760 100644 --- a/tools/build/Makefile.include +++ b/tools/build/Makefile.include @@ -4,7 +4,7 @@ ifdef CROSS_COMPILE fixdep: else fixdep: - $(Q)$(MAKE) -C $(srctree)/tools/build fixdep + $(Q)$(MAKE) -C $(srctree)/tools/build CFLAGS= LDFLAGS= fixdep endif .PHONY: fixdep
Sometimes variables passed to tools/build is dangerous. For example, on my platform there is a gcc problem (gcc 4.8.1): It passes stackprotector-all feature check: $ gcc -fstack-protector-all./test.c $ echo $? 0 But requires LDFLAGS support if separete compiling and linking: $ gcc -fstack-protector-all -c ./test.c $ gcc ./test.o ./test.o: In function `main': test.c:(.text+0xb): undefined reference to `__stack_chk_guard' test.c:(.text+0x21): undefined reference to `__stack_chk_guard' collect2: error: ld returned 1 exit status $ gcc -fstack-protector-all ./test.o $ echo $? 0 $ gcc ./test.o -lssp $ echo $? 0 In this environment perf building throws an error: $ make BUILD: Doing 'make -j24' parallel build config/Makefile:344: No libunwind found. Please install libunwind-dev[el] >= 1.1 and/or set LIBUNWIND_DIR config/Makefile:403: No libaudit.h found, disables 'trace' tool, please install audit-libs-devel or libaudit-dev config/Makefile:418: slang not found, disables TUI support. Please install slang-devel or libslang-dev config/Makefile:432: GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev config/Makefile:564: No bfd.h/libbfd found, please install binutils-dev[el]/zlib-static/libiberty-dev to gain symbol demangling config/Makefile:606: No numa.h found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev CC fixdep.o LD fixdep-in.o LINK fixdep fixdep-in.o: In function `parse_dep_file': /kernel/tools/build/fixdep.c:47: undefined reference to `__stack_chk_guard' /kernel/tools/build/fixdep.c:117: undefined reference to `__stack_chk_guard' fixdep-in.o: In function `main': /kernel-hydrogen/tools/build/fixdep.c:156: undefined reference to `__stack_chk_guard' /kernel/tools/build/fixdep.c:168: undefined reference to `__stack_chk_guard' collect2: error: ld returned 1 exit status make[2]: *** [fixdep] Error 1 make[1]: *** [fixdep] Error 2 make: *** [all] Error 2 This is because CFLAGS in perf building pollutes CFLAGS used for fixdep, passes -fstack-protector-all to fixdep builder which is obviously not required. Since fixdep is a small host side tool, we should keep its CFLAGS/LDFLAGS simple anc clean. This patch clear CFLAGS and LDFLAGS passed to fixdep building, so such gcc problem won't block perf building. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> --- tools/build/Makefile.include | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/