[PATCH] kbuild: drop support for cc-ldoption

From: Nick Desaulniers
Date: Tue Apr 23 2019 - 17:27:50 EST


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@xxxxxxxxxxxxxxxx
Suggested-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
---
This should probably wait until all of the call sites have been cleaned
up. Masahiro sent them for arm and arm64, while I sent cleanups for all
the rest.


Documentation/kbuild/makefiles.txt | 14 --------------
scripts/Kbuild.include | 5 -----
2 files changed, 19 deletions(-)

diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt
index 03c065855eaf..d65ad5746f94 100644
--- 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.

- 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
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 7484b9d8272f..fbfb37d1bcc8 100644
--- 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))

-# 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))
--
2.21.0.593.g511ec345e18-goog