kbuild: drop support for cc-ldoption

If you want to see if your linker supports a certain flag, then ask the
linker directly with ld-option (not the compiler with cc-ldoption).
Checking for linker flag support is an antipattern that complicates the
usage of various linkers other than bfd via -fuse-ld={bfd|gold|lld}.

Cc: clang-built-linux@googlegroups.com
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt
index 03c065855eafb39e00179626bfd2a5106a945079..d65ad5746f9482c494bf6bef390308695f7eb35c 100644 (file)
--- a/Documentation/kbuild/makefiles.txt
+++ b/Documentation/kbuild/makefiles.txt
@@ -437,20 +437,6 @@ more details, with real examples.
        The second argument is optional, and if supplied will be used
        if first argument is not supported.
 
        The second argument is optional, and if supplied will be used
        if first argument is not supported.
 

-    cc-ldoption
-       cc-ldoption is used to check if $(CC) when used to link object files
-       supports the given option.  An optional second option may be
-       specified if first option are not supported.
-
-       Example:
-               #arch/x86/kernel/Makefile
-               vsyscall-flags += $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
-
-       In the above example, vsyscall-flags will be assigned the option
-       -Wl$(comma)--hash-style=sysv if it is supported by $(CC).
-       The second argument is optional, and if supplied will be used
-       if first argument is not supported.
-

     as-instr
        as-instr checks if the assembler reports a specific instruction
        and then outputs either option1 or option2
     as-instr
        as-instr checks if the assembler reports a specific instruction
        and then outputs either option1 or option2

diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index a675ce11a573094b0a959b38dfaea96e6c806e05..e2de6c4dce9074934a7f20acb0f616fa0deb1012 100644 (file)
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -138,11 +138,6 @@ cc-disable-warning = $(call try-run,\
 # Usage:  EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
 cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
 
 # Usage:  EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
 cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
 

-# cc-ldoption
-# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
-cc-ldoption = $(call try-run,\
-       $(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
-

 # ld-option
 # Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
 ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
 # ld-option
 # Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
 ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))