[PATCH v2 00/14] Remove clang's -Qunused-arguments from KBUILD_CPPFLAGS

[PATCH v2 00/14] Remove clang's -Qunused-arguments from KBUILD_CPPFLAGS

[Nathan Chancellor]

Hi all,

Clang can emit a few different warnings when it encounters a flag that it
recognizes but does not support internally. These warnings are elevated to
errors within {as,cc}-option via -Werror to catch unsupported flags that should
not be added to KBUILD_{A,C}FLAGS; see commit c3f0d0bc5b01 ("kbuild, LLVMLinux:
Add -Werror to cc-option to support clang").

If an unsupported flag is unconditionally to KBUILD_{A,C}FLAGS, all subsequent
{as,cc}-option will always fail, preventing supported and even potentially
necessary flags from getting adding to the tool flags.

One would expect these warnings to be visible in the kernel build logs since
they are added to KBUILD_{A,C}FLAGS but unfortunately, these warnings are
hidden with clang's -Qunused-arguments flag, which is added to KBUILD_CPPFLAGS
and used for both compiling and assembling files.

Patches 1-4 address the internal inconsistencies of invoking the assembler
within kbuild by using KBUILD_AFLAGS consistently and using '-x
assembler-with-cpp' over '-x assembler'. This matches how assembly files are
built across the kernel and helps avoid problems in situations where macro
definitions or warning flags are present in KBUILD_AFLAGS, which cause
instances of -Wunused-command-line-argument when the preprocessor is not called
to consume them. There were a couple of places in architecture code where this
change would break things so those are fixed first.

Patches 5-12 clean up warnings that will show up when -Qunused-argument is
dropped. I hope none of these are controversial.

Patch 13 turns two warnings into errors so that the presence of unused flags
cannot be easily ignored.

Patch 14 drops -Qunused-argument. This is done last so that it can be easily
reverted if need be.

This series has seen my personal test framework, which tests several different
configurations and architectures, with LLVM tip of tree (16.0.0). I have done
defconfig, allmodconfig, and allnoconfig builds for arm, arm64, i386, mips,
powerpc, riscv, s390, and x86_64 with GCC 12.2.0 as well but I am hoping the
rest of the test infrastructure will catch any lurking problems.

I would like this series to stay together so that there is no opportunity for
breakage so please consider giving acks so that this can be carried via the
kbuild tree (and many thanks to the people who have already provided such
tags).

---
Changes in v2:
- Pick up tags where provided (thank you everyone!)
- Patch 6 and 9: Clarify that '-s' is a compiler flag that is only relevant to
  the linking phase and remove all mention of the assembler's '-s' flag, as the
  assembler is never directly invoked (Nick, Segher)
- Patch 7: Move '-z noexecstack' into new ldflags-y variable (Nick)
- Patch 8: Reword commit message to explain the problem in a clearer manner
  (Nick)
- Link to v1: https://lore.kernel.org/r/20221228-drop-qunused-arguments-v1-0-658cbc8fc592@kernel.org

---
Nathan Chancellor (12):
      MIPS: Always use -Wa,-msoft-float and eliminate GAS_HAS_SET_HARDFLOAT
      MIPS: Prefer cc-option for additions to cflags
      powerpc: Remove linker flag from KBUILD_AFLAGS
      powerpc/vdso: Remove unused '-s' flag from ASFLAGS
      powerpc/vdso: Improve linker flags
      powerpc/vdso: Remove an unsupported flag from vgettimeofday-32.o with clang
      s390/vdso: Drop unused '-s' flag from KBUILD_AFLAGS_64
      s390/vdso: Drop '-shared' from KBUILD_CFLAGS_64
      s390/purgatory: Remove unused '-MD' and unnecessary '-c' flags
      drm/amd/display: Do not add '-mhard-float' to dml_ccflags for clang
      kbuild: Turn a couple more of clang's unused option warnings into errors
      kbuild: Stop using '-Qunused-arguments' with clang

Nick Desaulniers (2):
      x86/boot/compressed: prefer cc-option for CFLAGS additions
      kbuild: Update assembler calls to use proper flags and language target

 Makefile                                    |  1 -
 arch/mips/Makefile                          | 13 ++-------
 arch/mips/include/asm/asmmacro-32.h         |  4 +--
 arch/mips/include/asm/asmmacro.h            | 42 ++++++++++++++---------------
 arch/mips/include/asm/fpregdef.h            | 14 ----------
 arch/mips/include/asm/mipsregs.h            | 20 +++-----------
 arch/mips/kernel/genex.S                    |  2 +-
 arch/mips/kernel/r2300_fpu.S                |  4 +--
 arch/mips/kernel/r4k_fpu.S                  | 12 ++++-----
 arch/mips/kvm/fpu.S                         |  6 ++---
 arch/mips/loongson2ef/Platform              |  2 +-
 arch/powerpc/Makefile                       |  2 +-
 arch/powerpc/kernel/vdso/Makefile           | 25 +++++++++++------
 arch/s390/kernel/vdso64/Makefile            |  4 +--
 arch/s390/purgatory/Makefile                |  2 +-
 arch/x86/boot/compressed/Makefile           |  2 +-
 drivers/gpu/drm/amd/display/dc/dml/Makefile |  3 ++-
 scripts/Kconfig.include                     |  2 +-
 scripts/Makefile.clang                      |  2 ++
 scripts/Makefile.compiler                   |  8 +++---
 scripts/as-version.sh                       |  2 +-
 21 files changed, 74 insertions(+), 98 deletions(-)
---
base-commit: 88603b6dc419445847923fcb7fe5080067a30f98
change-id: 20221228-drop-qunused-arguments-0c5c7dae54fb

Best regards,
-- 
Nathan Chancellor <nathan@kernel.org>

[PATCH v2 02/14] MIPS: Always use -Wa,-msoft-float and eliminate GAS_HAS_SET_HARDFLOAT

[Nathan Chancellor]

-Wa,-msoft-float is tested with as-option, which will be a problem for
clang with an upcoming change to move as-option to use KBUILD_AFLAGS
instead of KBUILD_CFLAGS due to a lack of '-mno-abicalls' in
KBUILD_AFLAGS at the point that this check occurs; $(cflags-y) is added
to KBUILD_AFLAGS towards the end of this file.

  clang: error: ignoring '-fno-PIE' option as it cannot be used with implicit usage of -mabicalls and the N64 ABI [-Werror,-Woption-ignored]

This could be resolved by switching to a cc-option check but
'$(cflags-y)' would need to be added so that '-mno-abicalls' is present
for the test. However, this check is no longer necessary, as
-msoft-float is supported by all supported assembler versions (GNU as
2.25+ and LLVM 11+). Eliminate GAS_HAS_SET_HARDFLOAT and all of its
uses, inlining SET_HARDFLOAT where necessary.

Link: https://lore.kernel.org/202209101939.bvk64Fok-lkp@intel.com/
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
Cc: linux-mips@vger.kernel.org
---
 arch/mips/Makefile                  | 11 +---------
 arch/mips/include/asm/asmmacro-32.h |  4 ++--
 arch/mips/include/asm/asmmacro.h    | 42 ++++++++++++++++++-------------------
 arch/mips/include/asm/fpregdef.h    | 14 -------------
 arch/mips/include/asm/mipsregs.h    | 20 ++++--------------
 arch/mips/kernel/genex.S            |  2 +-
 arch/mips/kernel/r2300_fpu.S        |  4 ++--
 arch/mips/kernel/r4k_fpu.S          | 12 +++++------
 arch/mips/kvm/fpu.S                 |  6 +++---
 9 files changed, 40 insertions(+), 75 deletions(-)

diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index 490dea07d4e0..a00a6d94e16f 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -95,7 +95,7 @@ all-$(CONFIG_SYS_SUPPORTS_ZBOOT)+= vmlinuz
 # crossformat linking we rely on the elf2ecoff tool for format conversion.
 #
 cflags-y			+= -G 0 -mno-abicalls -fno-pic -pipe
-cflags-y			+= -msoft-float
+cflags-y			+= -msoft-float -Wa,-msoft-float
 LDFLAGS_vmlinux			+= -G 0 -static -n -nostdlib
 KBUILD_AFLAGS_MODULE		+= -mlong-calls
 KBUILD_CFLAGS_MODULE		+= -mlong-calls
@@ -104,15 +104,6 @@ ifeq ($(CONFIG_RELOCATABLE),y)
 LDFLAGS_vmlinux			+= --emit-relocs
 endif
 
-#
-# pass -msoft-float to GAS if it supports it.  However on newer binutils
-# (specifically newer than 2.24.51.20140728) we then also need to explicitly
-# set ".set hardfloat" in all files which manipulate floating point registers.
-#
-ifneq ($(call as-option,-Wa$(comma)-msoft-float,),)
-	cflags-y		+= -DGAS_HAS_SET_HARDFLOAT -Wa,-msoft-float
-endif
-
 cflags-y += -ffreestanding
 
 cflags-$(CONFIG_CPU_BIG_ENDIAN)		+= -EB
diff --git a/arch/mips/include/asm/asmmacro-32.h b/arch/mips/include/asm/asmmacro-32.h
index 1c08c1f7903c..83a4940b7c89 100644
--- a/arch/mips/include/asm/asmmacro-32.h
+++ b/arch/mips/include/asm/asmmacro-32.h
@@ -15,7 +15,7 @@
 
 	.macro	fpu_save_single thread tmp=t0
 	.set push
-	SET_HARDFLOAT
+	.set hardfloat
 	cfc1	\tmp,  fcr31
 	s.d	$f0,  THREAD_FPR0(\thread)
 	s.d	$f2,  THREAD_FPR2(\thread)
@@ -39,7 +39,7 @@
 
 	.macro	fpu_restore_single thread tmp=t0
 	.set push
-	SET_HARDFLOAT
+	.set hardfloat
 	lw	\tmp, THREAD_FCR31(\thread)
 	l.d	$f0,  THREAD_FPR0(\thread)
 	l.d	$f2,  THREAD_FPR2(\thread)
diff --git a/arch/mips/include/asm/asmmacro.h b/arch/mips/include/asm/asmmacro.h
index ca83ada7015f..1c4438f3f2ab 100644
--- a/arch/mips/include/asm/asmmacro.h
+++ b/arch/mips/include/asm/asmmacro.h
@@ -83,7 +83,7 @@
 
 	.macro	fpu_save_16even thread tmp=t0
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 	cfc1	\tmp, fcr31
 	sdc1	$f0,  THREAD_FPR0(\thread)
 	sdc1	$f2,  THREAD_FPR2(\thread)
@@ -109,7 +109,7 @@
 	.set	push
 	.set	mips64r2
 	.set	fp=64
-	SET_HARDFLOAT
+	.set	hardfloat
 	sdc1	$f1,  THREAD_FPR1(\thread)
 	sdc1	$f3,  THREAD_FPR3(\thread)
 	sdc1	$f5,  THREAD_FPR5(\thread)
@@ -142,7 +142,7 @@
 
 	.macro	fpu_restore_16even thread tmp=t0
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 	lw	\tmp, THREAD_FCR31(\thread)
 	ldc1	$f0,  THREAD_FPR0(\thread)
 	ldc1	$f2,  THREAD_FPR2(\thread)
@@ -168,7 +168,7 @@
 	.set	push
 	.set	mips64r2
 	.set	fp=64
-	SET_HARDFLOAT
+	.set	hardfloat
 	ldc1	$f1,  THREAD_FPR1(\thread)
 	ldc1	$f3,  THREAD_FPR3(\thread)
 	ldc1	$f5,  THREAD_FPR5(\thread)
@@ -373,7 +373,7 @@
 	.macro	_cfcmsa	rd, cs
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	insn_if_mips 0x787e0059 | (\cs << 11)
 	insn32_if_mm 0x587e0056 | (\cs << 11)
 	move	\rd, $1
@@ -383,7 +383,7 @@
 	.macro	_ctcmsa	cd, rs
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	move	$1, \rs
 	insn_if_mips 0x783e0819 | (\cd << 6)
 	insn32_if_mm 0x583e0816 | (\cd << 6)
@@ -393,7 +393,7 @@
 	.macro	ld_b	wd, off, base
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	PTR_ADDU $1, \base, \off
 	insn_if_mips 0x78000820 | (\wd << 6)
 	insn32_if_mm 0x58000807 | (\wd << 6)
@@ -403,7 +403,7 @@
 	.macro	ld_h	wd, off, base
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	PTR_ADDU $1, \base, \off
 	insn_if_mips 0x78000821 | (\wd << 6)
 	insn32_if_mm 0x58000817 | (\wd << 6)
@@ -413,7 +413,7 @@
 	.macro	ld_w	wd, off, base
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	PTR_ADDU $1, \base, \off
 	insn_if_mips 0x78000822 | (\wd << 6)
 	insn32_if_mm 0x58000827 | (\wd << 6)
@@ -423,7 +423,7 @@
 	.macro	ld_d	wd, off, base
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	PTR_ADDU $1, \base, \off
 	insn_if_mips 0x78000823 | (\wd << 6)
 	insn32_if_mm 0x58000837 | (\wd << 6)
@@ -433,7 +433,7 @@
 	.macro	st_b	wd, off, base
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	PTR_ADDU $1, \base, \off
 	insn_if_mips 0x78000824 | (\wd << 6)
 	insn32_if_mm 0x5800080f | (\wd << 6)
@@ -443,7 +443,7 @@
 	.macro	st_h	wd, off, base
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	PTR_ADDU $1, \base, \off
 	insn_if_mips 0x78000825 | (\wd << 6)
 	insn32_if_mm 0x5800081f | (\wd << 6)
@@ -453,7 +453,7 @@
 	.macro	st_w	wd, off, base
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	PTR_ADDU $1, \base, \off
 	insn_if_mips 0x78000826 | (\wd << 6)
 	insn32_if_mm 0x5800082f | (\wd << 6)
@@ -463,7 +463,7 @@
 	.macro	st_d	wd, off, base
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	PTR_ADDU $1, \base, \off
 	insn_if_mips 0x78000827 | (\wd << 6)
 	insn32_if_mm 0x5800083f | (\wd << 6)
@@ -473,7 +473,7 @@
 	.macro	copy_s_w	ws, n
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	insn_if_mips 0x78b00059 | (\n << 16) | (\ws << 11)
 	insn32_if_mm 0x58b00056 | (\n << 16) | (\ws << 11)
 	.set	pop
@@ -482,7 +482,7 @@
 	.macro	copy_s_d	ws, n
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	insn_if_mips 0x78b80059 | (\n << 16) | (\ws << 11)
 	insn32_if_mm 0x58b80056 | (\n << 16) | (\ws << 11)
 	.set	pop
@@ -491,7 +491,7 @@
 	.macro	insert_w	wd, n
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	insn_if_mips 0x79300819 | (\n << 16) | (\wd << 6)
 	insn32_if_mm 0x59300816 | (\n << 16) | (\wd << 6)
 	.set	pop
@@ -500,7 +500,7 @@
 	.macro	insert_d	wd, n
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	insn_if_mips 0x79380819 | (\n << 16) | (\wd << 6)
 	insn32_if_mm 0x59380816 | (\n << 16) | (\wd << 6)
 	.set	pop
@@ -553,7 +553,7 @@
 	st_d	29, THREAD_FPR29 - FPR_BASE_OFFS, FPR_BASE
 	st_d	30, THREAD_FPR30 - FPR_BASE_OFFS, FPR_BASE
 	st_d	31, THREAD_FPR31 - FPR_BASE_OFFS, FPR_BASE
-	SET_HARDFLOAT
+	.set	hardfloat
 	_cfcmsa	$1, MSA_CSR
 	sw	$1, THREAD_MSA_CSR(\thread)
 	.set	pop
@@ -562,7 +562,7 @@
 	.macro	msa_restore_all	thread
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	lw	$1, THREAD_MSA_CSR(\thread)
 	_ctcmsa	MSA_CSR, $1
 #ifdef TOOLCHAIN_SUPPORTS_MSA
@@ -618,7 +618,7 @@
 	.macro	msa_init_all_upper
 	.set	push
 	.set	noat
-	SET_HARDFLOAT
+	.set	hardfloat
 	not	$1, zero
 	msa_init_upper	0
 	msa_init_upper	1
diff --git a/arch/mips/include/asm/fpregdef.h b/arch/mips/include/asm/fpregdef.h
index f184ba088532..429481f9028d 100644
--- a/arch/mips/include/asm/fpregdef.h
+++ b/arch/mips/include/asm/fpregdef.h
@@ -14,20 +14,6 @@
 
 #include <asm/sgidefs.h>
 
-/*
- * starting with binutils 2.24.51.20140729, MIPS binutils warn about mixing
- * hardfloat and softfloat object files.  The kernel build uses soft-float by
- * default, so we also need to pass -msoft-float along to GAS if it supports it.
- * But this in turn causes assembler errors in files which access hardfloat
- * registers.  We detect if GAS supports "-msoft-float" in the Makefile and
- * explicitly put ".set hardfloat" where floating point registers are touched.
- */
-#ifdef GAS_HAS_SET_HARDFLOAT
-#define SET_HARDFLOAT .set hardfloat
-#else
-#define SET_HARDFLOAT
-#endif
-
 #if _MIPS_SIM == _MIPS_SIM_ABI32
 
 /*
diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h
index 99eeafe6dcab..2d53704d9f24 100644
--- a/arch/mips/include/asm/mipsregs.h
+++ b/arch/mips/include/asm/mipsregs.h
@@ -2367,7 +2367,7 @@ do {									\
 /*
  * Macros to access the floating point coprocessor control registers
  */
-#define _read_32bit_cp1_register(source, gas_hardfloat)			\
+#define read_32bit_cp1_register(source)					\
 ({									\
 	unsigned int __res;						\
 									\
@@ -2377,36 +2377,24 @@ do {									\
 	"	# gas fails to assemble cfc1 for some archs,	\n"	\
 	"	# like Octeon.					\n"	\
 	"	.set	mips1					\n"	\
-	"	"STR(gas_hardfloat)"				\n"	\
+	"	.set hardfloat					\n"	\
 	"	cfc1	%0,"STR(source)"			\n"	\
 	"	.set	pop					\n"	\
 	: "=r" (__res));						\
 	__res;								\
 })
 
-#define _write_32bit_cp1_register(dest, val, gas_hardfloat)		\
+#define write_32bit_cp1_register(dest, val)				\
 do {									\
 	__asm__ __volatile__(						\
 	"	.set	push					\n"	\
 	"	.set	reorder					\n"	\
-	"	"STR(gas_hardfloat)"				\n"	\
+	"	.set hardfloat					\n"	\
 	"	ctc1	%0,"STR(dest)"				\n"	\
 	"	.set	pop					\n"	\
 	: : "r" (val));							\
 } while (0)
 
-#ifdef GAS_HAS_SET_HARDFLOAT
-#define read_32bit_cp1_register(source)					\
-	_read_32bit_cp1_register(source, .set hardfloat)
-#define write_32bit_cp1_register(dest, val)				\
-	_write_32bit_cp1_register(dest, val, .set hardfloat)
-#else
-#define read_32bit_cp1_register(source)					\
-	_read_32bit_cp1_register(source, )
-#define write_32bit_cp1_register(dest, val)				\
-	_write_32bit_cp1_register(dest, val, )
-#endif
-
 #ifdef TOOLCHAIN_SUPPORTS_DSP
 #define rddsp(mask)							\
 ({									\
diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S
index 3425df6019c0..b6de8e88c1bd 100644
--- a/arch/mips/kernel/genex.S
+++ b/arch/mips/kernel/genex.S
@@ -480,7 +480,7 @@ NESTED(nmi_handler, PT_SIZE, sp)
 	.set	push
 	/* gas fails to assemble cfc1 for some archs (octeon).*/ \
 	.set	mips1
-	SET_HARDFLOAT
+	.set	hardfloat
 	cfc1	a1, fcr31
 	.set	pop
 	.endm
diff --git a/arch/mips/kernel/r2300_fpu.S b/arch/mips/kernel/r2300_fpu.S
index 2748c55820c2..6c745aa9e825 100644
--- a/arch/mips/kernel/r2300_fpu.S
+++ b/arch/mips/kernel/r2300_fpu.S
@@ -64,7 +64,7 @@ LEAF(_restore_fp)
  */
 LEAF(_save_fp_context)
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 	li	v0, 0					# assume success
 	cfc1	t1, fcr31
 	EX2(s.d $f0, 0(a0))
@@ -98,7 +98,7 @@ LEAF(_save_fp_context)
  */
 LEAF(_restore_fp_context)
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 	li	v0, 0					# assume success
 	EX(lw t0, (a1))
 	EX2(l.d $f0, 0(a0))
diff --git a/arch/mips/kernel/r4k_fpu.S b/arch/mips/kernel/r4k_fpu.S
index 2e687c60bc4f..4e8c98517d9d 100644
--- a/arch/mips/kernel/r4k_fpu.S
+++ b/arch/mips/kernel/r4k_fpu.S
@@ -26,7 +26,7 @@
 
 	.macro	EX insn, reg, src
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 	.set	nomacro
 .ex\@:	\insn	\reg, \src
 	.set	pop
@@ -98,14 +98,14 @@ LEAF(_init_msa_upper)
  */
 LEAF(_save_fp_context)
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 	cfc1	t1, fcr31
 	.set	pop
 
 #if defined(CONFIG_64BIT) || defined(CONFIG_CPU_MIPSR2) || \
     defined(CONFIG_CPU_MIPSR5) || defined(CONFIG_CPU_MIPSR6)
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR5)
 	.set	mips32r2
 	.set	fp=64
@@ -135,7 +135,7 @@ LEAF(_save_fp_context)
 #endif
 
 	.set push
-	SET_HARDFLOAT
+	.set	hardfloat
 	/* Store the 16 even double precision registers */
 	EX	sdc1 $f0, 0(a0)
 	EX	sdc1 $f2, 16(a0)
@@ -173,7 +173,7 @@ LEAF(_restore_fp_context)
 #if defined(CONFIG_64BIT) || defined(CONFIG_CPU_MIPSR2) || \
     defined(CONFIG_CPU_MIPSR5) || defined(CONFIG_CPU_MIPSR6)
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR5)
 	.set	mips32r2
 	.set	fp=64
@@ -201,7 +201,7 @@ LEAF(_restore_fp_context)
 1:	.set pop
 #endif
 	.set push
-	SET_HARDFLOAT
+	.set hardfloat
 	EX	ldc1 $f0, 0(a0)
 	EX	ldc1 $f2, 16(a0)
 	EX	ldc1 $f4, 32(a0)
diff --git a/arch/mips/kvm/fpu.S b/arch/mips/kvm/fpu.S
index 16f17c6390dd..eb2e8cc3532f 100644
--- a/arch/mips/kvm/fpu.S
+++ b/arch/mips/kvm/fpu.S
@@ -22,7 +22,7 @@
 
 LEAF(__kvm_save_fpu)
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 	.set	fp=64
 	mfc0	t0, CP0_STATUS
 	sll     t0, t0, 5			# is Status.FR set?
@@ -66,7 +66,7 @@ LEAF(__kvm_save_fpu)
 
 LEAF(__kvm_restore_fpu)
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 	.set	fp=64
 	mfc0	t0, CP0_STATUS
 	sll     t0, t0, 5			# is Status.FR set?
@@ -110,7 +110,7 @@ LEAF(__kvm_restore_fpu)
 
 LEAF(__kvm_restore_fcsr)
 	.set	push
-	SET_HARDFLOAT
+	.set	hardfloat
 	lw	t0, VCPU_FCR31(a0)
 	/*
 	 * The ctc1 must stay at this offset in __kvm_restore_fcsr.

-- 
2.39.0

[PATCH v2 03/14] MIPS: Prefer cc-option for additions to cflags

[Nathan Chancellor]

A future change will switch as-option to use KBUILD_AFLAGS instead of
KBUILD_CFLAGS to allow clang to drop -Qunused-arguments, which may cause
issues if the flag being tested requires a flag previously added to
KBUILD_CFLAGS but not KBUILD_AFLAGS. Use cc-option for cflags additions
so that the flags are tested properly.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
Cc: linux-mips@vger.kernel.org
---
 arch/mips/Makefile             | 2 +-
 arch/mips/loongson2ef/Platform | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index a00a6d94e16f..04e46ec24319 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -143,7 +143,7 @@ cflags-y += -fno-stack-check
 #
 # Avoid this by explicitly disabling that assembler behaviour.
 #
-cflags-y += $(call as-option,-Wa$(comma)-mno-fix-loongson3-llsc,)
+cflags-y += $(call cc-option,-Wa$(comma)-mno-fix-loongson3-llsc,)
 
 #
 # CPU-dependent compiler/assembler options for optimization.
diff --git a/arch/mips/loongson2ef/Platform b/arch/mips/loongson2ef/Platform
index eebabf9df6ac..c6f7a4b95997 100644
--- a/arch/mips/loongson2ef/Platform
+++ b/arch/mips/loongson2ef/Platform
@@ -25,7 +25,7 @@ cflags-$(CONFIG_CPU_LOONGSON2F) += -march=loongson2f
 # binutils does not merge support for the flag then we can revisit & remove
 # this later - for now it ensures vendor toolchains don't cause problems.
 #
-cflags-$(CONFIG_CPU_LOONGSON2EF)	+= $(call as-option,-Wa$(comma)-mno-fix-loongson3-llsc,)
+cflags-$(CONFIG_CPU_LOONGSON2EF)	+= $(call cc-option,-Wa$(comma)-mno-fix-loongson3-llsc,)
 
 # Enable the workarounds for Loongson2f
 ifdef CONFIG_CPU_LOONGSON2F_WORKAROUNDS

-- 
2.39.0

Re: [PATCH v2 00/14] Remove clang's -Qunused-arguments from KBUILD_CPPFLAGS

[Masahiro Yamada]

On Thu, Jan 12, 2023 at 12:05 PM Nathan Chancellor <nathan@kernel.org> wrote:
>
> Hi all,
>
> Clang can emit a few different warnings when it encounters a flag that it
> recognizes but does not support internally. These warnings are elevated to
> errors within {as,cc}-option via -Werror to catch unsupported flags that should
> not be added to KBUILD_{A,C}FLAGS; see commit c3f0d0bc5b01 ("kbuild, LLVMLinux:
> Add -Werror to cc-option to support clang").
>
> If an unsupported flag is unconditionally to KBUILD_{A,C}FLAGS, all subsequent
> {as,cc}-option will always fail, preventing supported and even potentially
> necessary flags from getting adding to the tool flags.
>
> One would expect these warnings to be visible in the kernel build logs since
> they are added to KBUILD_{A,C}FLAGS but unfortunately, these warnings are
> hidden with clang's -Qunused-arguments flag, which is added to KBUILD_CPPFLAGS
> and used for both compiling and assembling files.
>
> Patches 1-4 address the internal inconsistencies of invoking the assembler
> within kbuild by using KBUILD_AFLAGS consistently and using '-x
> assembler-with-cpp' over '-x assembler'. This matches how assembly files are
> built across the kernel and helps avoid problems in situations where macro
> definitions or warning flags are present in KBUILD_AFLAGS, which cause
> instances of -Wunused-command-line-argument when the preprocessor is not called
> to consume them. There were a couple of places in architecture code where this
> change would break things so those are fixed first.
>
> Patches 5-12 clean up warnings that will show up when -Qunused-argument is
> dropped. I hope none of these are controversial.
>
> Patch 13 turns two warnings into errors so that the presence of unused flags
> cannot be easily ignored.
>
> Patch 14 drops -Qunused-argument. This is done last so that it can be easily
> reverted if need be.
>
> This series has seen my personal test framework, which tests several different
> configurations and architectures, with LLVM tip of tree (16.0.0). I have done
> defconfig, allmodconfig, and allnoconfig builds for arm, arm64, i386, mips,
> powerpc, riscv, s390, and x86_64 with GCC 12.2.0 as well but I am hoping the
> rest of the test infrastructure will catch any lurking problems.
>
> I would like this series to stay together so that there is no opportunity for
> breakage so please consider giving acks so that this can be carried via the
> kbuild tree (and many thanks to the people who have already provided such
> tags).


All applied to linux-kbuild. Thanks.

I left small comments in 07/14.








> ---
> Changes in v2:
> - Pick up tags where provided (thank you everyone!)
> - Patch 6 and 9: Clarify that '-s' is a compiler flag that is only relevant to
>   the linking phase and remove all mention of the assembler's '-s' flag, as the
>   assembler is never directly invoked (Nick, Segher)
> - Patch 7: Move '-z noexecstack' into new ldflags-y variable (Nick)
> - Patch 8: Reword commit message to explain the problem in a clearer manner
>   (Nick)
> - Link to v1: https://lore.kernel.org/r/20221228-drop-qunused-arguments-v1-0-658cbc8fc592@kernel.org
>
> ---
> Nathan Chancellor (12):
>       MIPS: Always use -Wa,-msoft-float and eliminate GAS_HAS_SET_HARDFLOAT
>       MIPS: Prefer cc-option for additions to cflags
>       powerpc: Remove linker flag from KBUILD_AFLAGS
>       powerpc/vdso: Remove unused '-s' flag from ASFLAGS
>       powerpc/vdso: Improve linker flags
>       powerpc/vdso: Remove an unsupported flag from vgettimeofday-32.o with clang
>       s390/vdso: Drop unused '-s' flag from KBUILD_AFLAGS_64
>       s390/vdso: Drop '-shared' from KBUILD_CFLAGS_64
>       s390/purgatory: Remove unused '-MD' and unnecessary '-c' flags
>       drm/amd/display: Do not add '-mhard-float' to dml_ccflags for clang
>       kbuild: Turn a couple more of clang's unused option warnings into errors
>       kbuild: Stop using '-Qunused-arguments' with clang
>
> Nick Desaulniers (2):
>       x86/boot/compressed: prefer cc-option for CFLAGS additions
>       kbuild: Update assembler calls to use proper flags and language target
>
>  Makefile                                    |  1 -
>  arch/mips/Makefile                          | 13 ++-------
>  arch/mips/include/asm/asmmacro-32.h         |  4 +--
>  arch/mips/include/asm/asmmacro.h            | 42 ++++++++++++++---------------
>  arch/mips/include/asm/fpregdef.h            | 14 ----------
>  arch/mips/include/asm/mipsregs.h            | 20 +++-----------
>  arch/mips/kernel/genex.S                    |  2 +-
>  arch/mips/kernel/r2300_fpu.S                |  4 +--
>  arch/mips/kernel/r4k_fpu.S                  | 12 ++++-----
>  arch/mips/kvm/fpu.S                         |  6 ++---
>  arch/mips/loongson2ef/Platform              |  2 +-
>  arch/powerpc/Makefile                       |  2 +-
>  arch/powerpc/kernel/vdso/Makefile           | 25 +++++++++++------
>  arch/s390/kernel/vdso64/Makefile            |  4 +--
>  arch/s390/purgatory/Makefile                |  2 +-
>  arch/x86/boot/compressed/Makefile           |  2 +-
>  drivers/gpu/drm/amd/display/dc/dml/Makefile |  3 ++-
>  scripts/Kconfig.include                     |  2 +-
>  scripts/Makefile.clang                      |  2 ++
>  scripts/Makefile.compiler                   |  8 +++---
>  scripts/as-version.sh                       |  2 +-
>  21 files changed, 74 insertions(+), 98 deletions(-)
> ---
> base-commit: 88603b6dc419445847923fcb7fe5080067a30f98
> change-id: 20221228-drop-qunused-arguments-0c5c7dae54fb
>
> Best regards,
> --
> Nathan Chancellor <nathan@kernel.org>
>


--
Best Regards
Masahiro Yamada

Re: [PATCH v2 00/14] Remove clang's -Qunused-arguments from KBUILD_CPPFLAGS

[Naresh Kamboju]

Hi Nathan,

On Thu, 12 Jan 2023 at 08:35, Nathan Chancellor <nathan@kernel.org> wrote:
>
> Hi all,
>
> Clang can emit a few different warnings when it encounters a flag that it
> recognizes but does not support internally. These warnings are elevated to
> errors within {as,cc}-option via -Werror to catch unsupported flags that should
> not be added to KBUILD_{A,C}FLAGS; see commit c3f0d0bc5b01 ("kbuild, LLVMLinux:
> Add -Werror to cc-option to support clang").
>
> If an unsupported flag is unconditionally to KBUILD_{A,C}FLAGS, all subsequent
> {as,cc}-option will always fail, preventing supported and even potentially
> necessary flags from getting adding to the tool flags.
>
> One would expect these warnings to be visible in the kernel build logs since
> they are added to KBUILD_{A,C}FLAGS but unfortunately, these warnings are
> hidden with clang's -Qunused-arguments flag, which is added to KBUILD_CPPFLAGS
> and used for both compiling and assembling files.
>
> Patches 1-4 address the internal inconsistencies of invoking the assembler
> within kbuild by using KBUILD_AFLAGS consistently and using '-x
> assembler-with-cpp' over '-x assembler'. This matches how assembly files are
> built across the kernel and helps avoid problems in situations where macro
> definitions or warning flags are present in KBUILD_AFLAGS, which cause
> instances of -Wunused-command-line-argument when the preprocessor is not called
> to consume them. There were a couple of places in architecture code where this
> change would break things so those are fixed first.
>
> Patches 5-12 clean up warnings that will show up when -Qunused-argument is
> dropped. I hope none of these are controversial.
>
> Patch 13 turns two warnings into errors so that the presence of unused flags
> cannot be easily ignored.
>
> Patch 14 drops -Qunused-argument. This is done last so that it can be easily
> reverted if need be.
>
> This series has seen my personal test framework, which tests several different
> configurations and architectures, with LLVM tip of tree (16.0.0). I have done
> defconfig, allmodconfig, and allnoconfig builds for arm, arm64, i386, mips,
> powerpc, riscv, s390, and x86_64 with GCC 12.2.0 as well but I am hoping the
> rest of the test infrastructure will catch any lurking problems.
>
> I would like this series to stay together so that there is no opportunity for
> breakage so please consider giving acks so that this can be carried via the
> kbuild tree (and many thanks to the people who have already provided such
> tags).
>
> ---
> Changes in v2:
> - Pick up tags where provided (thank you everyone!)
> - Patch 6 and 9: Clarify that '-s' is a compiler flag that is only relevant to
>   the linking phase and remove all mention of the assembler's '-s' flag, as the
>   assembler is never directly invoked (Nick, Segher)
> - Patch 7: Move '-z noexecstack' into new ldflags-y variable (Nick)
> - Patch 8: Reword commit message to explain the problem in a clearer manner
>   (Nick)
> - Link to v1: https://lore.kernel.org/r/20221228-drop-qunused-arguments-v1-0-658cbc8fc592@kernel.org
>
> ---
> Nathan Chancellor (12):
>       MIPS: Always use -Wa,-msoft-float and eliminate GAS_HAS_SET_HARDFLOAT
>       MIPS: Prefer cc-option for additions to cflags
>       powerpc: Remove linker flag from KBUILD_AFLAGS
>       powerpc/vdso: Remove unused '-s' flag from ASFLAGS
>       powerpc/vdso: Improve linker flags
>       powerpc/vdso: Remove an unsupported flag from vgettimeofday-32.o with clang
>       s390/vdso: Drop unused '-s' flag from KBUILD_AFLAGS_64
>       s390/vdso: Drop '-shared' from KBUILD_CFLAGS_64
>       s390/purgatory: Remove unused '-MD' and unnecessary '-c' flags
>       drm/amd/display: Do not add '-mhard-float' to dml_ccflags for clang
>       kbuild: Turn a couple more of clang's unused option warnings into errors
>       kbuild: Stop using '-Qunused-arguments' with clang
>
> Nick Desaulniers (2):
>       x86/boot/compressed: prefer cc-option for CFLAGS additions
>       kbuild: Update assembler calls to use proper flags and language target
>
>  Makefile                                    |  1 -
>  arch/mips/Makefile                          | 13 ++-------
>  arch/mips/include/asm/asmmacro-32.h         |  4 +--
>  arch/mips/include/asm/asmmacro.h            | 42 ++++++++++++++---------------
>  arch/mips/include/asm/fpregdef.h            | 14 ----------
>  arch/mips/include/asm/mipsregs.h            | 20 +++-----------
>  arch/mips/kernel/genex.S                    |  2 +-
>  arch/mips/kernel/r2300_fpu.S                |  4 +--
>  arch/mips/kernel/r4k_fpu.S                  | 12 ++++-----
>  arch/mips/kvm/fpu.S                         |  6 ++---
>  arch/mips/loongson2ef/Platform              |  2 +-
>  arch/powerpc/Makefile                       |  2 +-
>  arch/powerpc/kernel/vdso/Makefile           | 25 +++++++++++------
>  arch/s390/kernel/vdso64/Makefile            |  4 +--
>  arch/s390/purgatory/Makefile                |  2 +-
>  arch/x86/boot/compressed/Makefile           |  2 +-
>  drivers/gpu/drm/amd/display/dc/dml/Makefile |  3 ++-
>  scripts/Kconfig.include                     |  2 +-
>  scripts/Makefile.clang                      |  2 ++
>  scripts/Makefile.compiler                   |  8 +++---
>  scripts/as-version.sh                       |  2 +-
>  21 files changed, 74 insertions(+), 98 deletions(-)


FYI,
[ please provide comments, feedback and improvements on build/ ltp smoke tests ]

LKFT test farm have fetched your patch series [1]
[PATCH v2 00/14] Remove clang's -Qunused-arguments from KBUILD_CPPFLAGS
 [1] https://lore.kernel.org/llvm/20221228-drop-qunused-arguments-v2-0-9adbddd20d86@kernel.org/

Following build warnings and errors reported.

sh:
gcc-11-defconfig — FAIL
gcc-11-shx3_defconfig — FAIL
https://qa-reports.linaro.org/~anders.roxell/linux-mainline-patches/build/https___lore_kernel_org_llvm_20221228-drop-qunused-arguments-v2-1-9adbddd20d86_kernel_org/testrun/14221835/suite/build/tests/

mainline getting passed.
https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc5/testrun/14298156/suite/build/test/gcc-11-defconfig/history/
https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc5/testrun/14298156/suite/build/test/gcc-11-shx3_defconfig/history/

Build error:
In function 'follow_pmd_mask',
    inlined from 'follow_pud_mask' at /builds/linux/mm/gup.c:735:9,
    inlined from 'follow_p4d_mask' at /builds/linux/mm/gup.c:752:9,
    inlined from 'follow_page_mask' at /builds/linux/mm/gup.c:809:9:
/builds/linux/include/linux/compiler_types.h:358:45: error: call to
'__compiletime_assert_263' declared with attribute error: Unsupported
access size for {READ,WRITE}_ONCE().
  358 |         _compiletime_assert(condition, msg,
__compiletime_assert_, __COUNTER__)


s390:
clang-15-defconfig — FAIL
https://qa-reports.linaro.org/~anders.roxell/linux-mainline-patches/build/https___lore_kernel_org_llvm_20221228-drop-qunused-arguments-v2-1-9adbddd20d86_kernel_org/testrun/14221913/suite/build/tests/

mainline getting passed.
https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc5/testrun/14300495/suite/build/test/clang-15-defconfig/history/

Build error:
make --silent --keep-going --jobs=8
O=/home/tuxbuild/.cache/tuxmake/builds/1/build LLVM_IAS=0 ARCH=s390
CROSS_COMPILE=s390x-linux-gnu- 'HOSTCC=sccache clang' 'CC=sccache
clang'
`.exit.text' referenced in section `__jump_table' of fs/fuse/inode.o:
defined in discarded section `.exit.text' of fs/fuse/inode.o
`.exit.text' referenced in section `__jump_table' of fs/fuse/inode.o:
defined in discarded section `.exit.text' of fs/fuse/inode.o
`.exit.text' referenced in section `__bug_table' of crypto/algboss.o:
defined in discarded section `.exit.text' of crypto/algboss.o
`.exit.text' referenced in section `__bug_table' of drivers/scsi/sd.o:
defined in discarded section `.exit.text' of drivers/scsi/sd.o
`.exit.text' referenced in section `__jump_table' of drivers/md/md.o:
defined in discarded section `.exit.text' of drivers/md/md.o
`.exit.text' referenced in section `__jump_table' of drivers/md/md.o:
defined in discarded section `.exit.text' of drivers/md/md.o
`.exit.text' referenced in section `.altinstructions' of
drivers/md/md.o: defined in discarded section `.exit.text' of
drivers/md/md.o
`.exit.text' referenced in section `.altinstructions' of
drivers/md/md.o: defined in discarded section `.exit.text' of
drivers/md/md.o
`.exit.text' referenced in section `.altinstructions' of
net/iucv/iucv.o: defined in discarded section `.exit.text' of
net/iucv/iucv.o
`.exit.text' referenced in section `__bug_table' of
drivers/s390/cio/qdio_thinint.o: defined in discarded section
`.exit.text' of drivers/s390/cio/qdio_thinint.o
`.exit.text' referenced in section `__bug_table' of
drivers/s390/net/qeth_l3_main.o: defined in discarded section
`.exit.text' of drivers/s390/net/qeth_l3_main.o
`.exit.text' referenced in section `__bug_table' of
drivers/s390/net/qeth_l3_main.o: defined in discarded section
`.exit.text' of drivers/s390/net/qeth_l3_main.o
s390x-linux-gnu-ld: BFD (GNU Binutils for Debian) 2.35.2 assertion
fail ../../bfd/elf64-s390.c:3349
make[2]: *** [/builds/linux/scripts/Makefile.vmlinux:34: vmlinux] Error 1

But,
Build and boot pass on arm64, arm, x86_64 and i386.
Build test performed for mips, parisc, riscv, s390, sh, sparc and
powerpc (known build errors for maple_defconfig and cell_defconfig),

Please refer following link for detailed build, boot, LTP smoketest.
https://qa-reports.linaro.org/~anders.roxell/linux-mainline-patches/build/https___lore_kernel_org_llvm_20221228-drop-qunused-arguments-v2-1-9adbddd20d86_kernel_org/?failures_only=false&results_layout=table#!#test-results

Best regards
Naresh Kamboju

--
Linaro LKFT
https://lkft.linaro.org

> ---
> base-commit: 88603b6dc419445847923fcb7fe5080067a30f98
> change-id: 20221228-drop-qunused-arguments-0c5c7dae54fb
>
> Best regards,
> --
> Nathan Chancellor <nathan@kernel.org>
>
>

Re: [PATCH v2 00/14] Remove clang's -Qunused-arguments from KBUILD_CPPFLAGS

[Nathan Chancellor]

Hi Naresh,

On Mon, Jan 23, 2023 at 07:28:10PM +0530, Naresh Kamboju wrote:
> FYI,
> [ please provide comments, feedback and improvements on build/ ltp smoke tests ]
> 
> LKFT test farm have fetched your patch series [1]
> [PATCH v2 00/14] Remove clang's -Qunused-arguments from KBUILD_CPPFLAGS
>  [1] https://lore.kernel.org/llvm/20221228-drop-qunused-arguments-v2-0-9adbddd20d86@kernel.org/

Thank you a lot for testing this series, it is much appreciated!

It looks like this was applied on top of 6.2-rc3 if I am reading your
logs right but your mainline testing is recent, 6.2-rc5. I think the
errors you are seeing here are just existing mainline regressions that
were later fixed.

> Following build warnings and errors reported.
> 
> sh:
> gcc-11-defconfig — FAIL
> gcc-11-shx3_defconfig — FAIL
> https://qa-reports.linaro.org/~anders.roxell/linux-mainline-patches/build/https___lore_kernel_org_llvm_20221228-drop-qunused-arguments-v2-1-9adbddd20d86_kernel_org/testrun/14221835/suite/build/tests/
> 
> mainline getting passed.
> https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc5/testrun/14298156/suite/build/test/gcc-11-defconfig/history/
> https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc5/testrun/14298156/suite/build/test/gcc-11-shx3_defconfig/history/
> 
> Build error:
> In function 'follow_pmd_mask',
>     inlined from 'follow_pud_mask' at /builds/linux/mm/gup.c:735:9,
>     inlined from 'follow_p4d_mask' at /builds/linux/mm/gup.c:752:9,
>     inlined from 'follow_page_mask' at /builds/linux/mm/gup.c:809:9:
> /builds/linux/include/linux/compiler_types.h:358:45: error: call to
> '__compiletime_assert_263' declared with attribute error: Unsupported
> access size for {READ,WRITE}_ONCE().
>   358 |         _compiletime_assert(condition, msg,
> __compiletime_assert_, __COUNTER__)

I think this was fixed with mainline commit 526970be53d5 ("sh/mm: Fix
pmd_t for real"), released in 6.2-rc4. You can see a previous build
failing in the same manner:

https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc3-9-g5a41237ad1d4/testrun/14056384/suite/build/tests/

> s390:
> clang-15-defconfig — FAIL
> https://qa-reports.linaro.org/~anders.roxell/linux-mainline-patches/build/https___lore_kernel_org_llvm_20221228-drop-qunused-arguments-v2-1-9adbddd20d86_kernel_org/testrun/14221913/suite/build/tests/
> 
> mainline getting passed.
> https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc5/testrun/14300495/suite/build/test/clang-15-defconfig/history/
> 
> Build error:
> make --silent --keep-going --jobs=8
> O=/home/tuxbuild/.cache/tuxmake/builds/1/build LLVM_IAS=0 ARCH=s390
> CROSS_COMPILE=s390x-linux-gnu- 'HOSTCC=sccache clang' 'CC=sccache
> clang'
> `.exit.text' referenced in section `__jump_table' of fs/fuse/inode.o:
> defined in discarded section `.exit.text' of fs/fuse/inode.o
> `.exit.text' referenced in section `__jump_table' of fs/fuse/inode.o:
> defined in discarded section `.exit.text' of fs/fuse/inode.o
> `.exit.text' referenced in section `__bug_table' of crypto/algboss.o:
> defined in discarded section `.exit.text' of crypto/algboss.o
> `.exit.text' referenced in section `__bug_table' of drivers/scsi/sd.o:
> defined in discarded section `.exit.text' of drivers/scsi/sd.o
> `.exit.text' referenced in section `__jump_table' of drivers/md/md.o:
> defined in discarded section `.exit.text' of drivers/md/md.o
> `.exit.text' referenced in section `__jump_table' of drivers/md/md.o:
> defined in discarded section `.exit.text' of drivers/md/md.o
> `.exit.text' referenced in section `.altinstructions' of
> drivers/md/md.o: defined in discarded section `.exit.text' of
> drivers/md/md.o
> `.exit.text' referenced in section `.altinstructions' of
> drivers/md/md.o: defined in discarded section `.exit.text' of
> drivers/md/md.o
> `.exit.text' referenced in section `.altinstructions' of
> net/iucv/iucv.o: defined in discarded section `.exit.text' of
> net/iucv/iucv.o
> `.exit.text' referenced in section `__bug_table' of
> drivers/s390/cio/qdio_thinint.o: defined in discarded section
> `.exit.text' of drivers/s390/cio/qdio_thinint.o
> `.exit.text' referenced in section `__bug_table' of
> drivers/s390/net/qeth_l3_main.o: defined in discarded section
> `.exit.text' of drivers/s390/net/qeth_l3_main.o
> `.exit.text' referenced in section `__bug_table' of
> drivers/s390/net/qeth_l3_main.o: defined in discarded section
> `.exit.text' of drivers/s390/net/qeth_l3_main.o
> s390x-linux-gnu-ld: BFD (GNU Binutils for Debian) 2.35.2 assertion
> fail ../../bfd/elf64-s390.c:3349
> make[2]: *** [/builds/linux/scripts/Makefile.vmlinux:34: vmlinux] Error 1

This should be fixed with mainline commit a494398bde27 ("s390: define
RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36"), released in
6.2-rc4 as well. Same as before, visible in mainline at one point
without this series:

https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc3-9-g5a41237ad1d4/testrun/14057142/suite/build/tests/

> But,
> Build and boot pass on arm64, arm, x86_64 and i386.
> Build test performed for mips, parisc, riscv, s390, sh, sparc and
> powerpc (known build errors for maple_defconfig and cell_defconfig),

Good to hear!

Please consider retesting this series on top of 6.2-rc5 or testing the
current kbuild tree, which has this series applied in it:

https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git/log/?h=for-next

Cheers,
Nathan

Re: [PATCH v2 00/14] Remove clang's -Qunused-arguments from KBUILD_CPPFLAGS

[Naresh Kamboju]

Hi Nathan,

On Mon, 23 Jan 2023 at 21:41, Nathan Chancellor <nathan@kernel.org> wrote:
>
> Hi Naresh,
>
> On Mon, Jan 23, 2023 at 07:28:10PM +0530, Naresh Kamboju wrote:
> > FYI,
> > [ please provide comments, feedback and improvements on build/ ltp smoke tests ]
> >
> > LKFT test farm have fetched your patch series [1]
> > [PATCH v2 00/14] Remove clang's -Qunused-arguments from KBUILD_CPPFLAGS
> >  [1] https://lore.kernel.org/llvm/20221228-drop-qunused-arguments-v2-0-9adbddd20d86@kernel.org/
>
> Thank you a lot for testing this series, it is much appreciated!
>
> It looks like this was applied on top of 6.2-rc3 if I am reading your
> logs right but your mainline testing is recent, 6.2-rc5. I think the
> errors you are seeing here are just existing mainline regressions that
> were later fixed.
>
> > Following build warnings and errors reported.
> >
> > sh:
> > gcc-11-defconfig — FAIL
> > gcc-11-shx3_defconfig — FAIL
> > https://qa-reports.linaro.org/~anders.roxell/linux-mainline-patches/build/https___lore_kernel_org_llvm_20221228-drop-qunused-arguments-v2-1-9adbddd20d86_kernel_org/testrun/14221835/suite/build/tests/
> >
> > mainline getting passed.
> > https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc5/testrun/14298156/suite/build/test/gcc-11-defconfig/history/
> > https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc5/testrun/14298156/suite/build/test/gcc-11-shx3_defconfig/history/
> >
> > Build error:
> > In function 'follow_pmd_mask',
> >     inlined from 'follow_pud_mask' at /builds/linux/mm/gup.c:735:9,
> >     inlined from 'follow_p4d_mask' at /builds/linux/mm/gup.c:752:9,
> >     inlined from 'follow_page_mask' at /builds/linux/mm/gup.c:809:9:
> > /builds/linux/include/linux/compiler_types.h:358:45: error: call to
> > '__compiletime_assert_263' declared with attribute error: Unsupported
> > access size for {READ,WRITE}_ONCE().
> >   358 |         _compiletime_assert(condition, msg,
> > __compiletime_assert_, __COUNTER__)
>
> I think this was fixed with mainline commit 526970be53d5 ("sh/mm: Fix
> pmd_t for real"), released in 6.2-rc4. You can see a previous build
> failing in the same manner:
>
> https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc3-9-g5a41237ad1d4/testrun/14056384/suite/build/tests/
>
> > s390:
> > clang-15-defconfig — FAIL
> > https://qa-reports.linaro.org/~anders.roxell/linux-mainline-patches/build/https___lore_kernel_org_llvm_20221228-drop-qunused-arguments-v2-1-9adbddd20d86_kernel_org/testrun/14221913/suite/build/tests/
> >
> > mainline getting passed.
> > https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc5/testrun/14300495/suite/build/test/clang-15-defconfig/history/
> >
> > Build error:
> > make --silent --keep-going --jobs=8
> > O=/home/tuxbuild/.cache/tuxmake/builds/1/build LLVM_IAS=0 ARCH=s390
> > CROSS_COMPILE=s390x-linux-gnu- 'HOSTCC=sccache clang' 'CC=sccache
> > clang'
> > `.exit.text' referenced in section `__jump_table' of fs/fuse/inode.o:
> > defined in discarded section `.exit.text' of fs/fuse/inode.o
> > `.exit.text' referenced in section `__jump_table' of fs/fuse/inode.o:
> > defined in discarded section `.exit.text' of fs/fuse/inode.o
> > `.exit.text' referenced in section `__bug_table' of crypto/algboss.o:
> > defined in discarded section `.exit.text' of crypto/algboss.o
> > `.exit.text' referenced in section `__bug_table' of drivers/scsi/sd.o:
> > defined in discarded section `.exit.text' of drivers/scsi/sd.o
> > `.exit.text' referenced in section `__jump_table' of drivers/md/md.o:
> > defined in discarded section `.exit.text' of drivers/md/md.o
> > `.exit.text' referenced in section `__jump_table' of drivers/md/md.o:
> > defined in discarded section `.exit.text' of drivers/md/md.o
> > `.exit.text' referenced in section `.altinstructions' of
> > drivers/md/md.o: defined in discarded section `.exit.text' of
> > drivers/md/md.o
> > `.exit.text' referenced in section `.altinstructions' of
> > drivers/md/md.o: defined in discarded section `.exit.text' of
> > drivers/md/md.o
> > `.exit.text' referenced in section `.altinstructions' of
> > net/iucv/iucv.o: defined in discarded section `.exit.text' of
> > net/iucv/iucv.o
> > `.exit.text' referenced in section `__bug_table' of
> > drivers/s390/cio/qdio_thinint.o: defined in discarded section
> > `.exit.text' of drivers/s390/cio/qdio_thinint.o
> > `.exit.text' referenced in section `__bug_table' of
> > drivers/s390/net/qeth_l3_main.o: defined in discarded section
> > `.exit.text' of drivers/s390/net/qeth_l3_main.o
> > `.exit.text' referenced in section `__bug_table' of
> > drivers/s390/net/qeth_l3_main.o: defined in discarded section
> > `.exit.text' of drivers/s390/net/qeth_l3_main.o
> > s390x-linux-gnu-ld: BFD (GNU Binutils for Debian) 2.35.2 assertion
> > fail ../../bfd/elf64-s390.c:3349
> > make[2]: *** [/builds/linux/scripts/Makefile.vmlinux:34: vmlinux] Error 1
>
> This should be fixed with mainline commit a494398bde27 ("s390: define
> RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36"), released in
> 6.2-rc4 as well. Same as before, visible in mainline at one point
> without this series:
>
> https://qa-reports.linaro.org/lkft/linux-mainline-master/build/v6.2-rc3-9-g5a41237ad1d4/testrun/14057142/suite/build/tests/
>
> > But,
> > Build and boot pass on arm64, arm, x86_64 and i386.
> > Build test performed for mips, parisc, riscv, s390, sh, sparc and
> > powerpc (known build errors for maple_defconfig and cell_defconfig),
>
> Good to hear!
>
> Please consider retesting this series on top of 6.2-rc5 or testing the
> current kbuild tree, which has this series applied in it:

This is the perfect place to test.

> https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git/log/?h=for-next

Build test pass on arm, arm64, i386, mips, parisc, powerpc, riscv, s390, sh,
sparc and x86_64.
Boot and LTP smoke pass on qemu-arm64, qemu-armv7, qemu-i386 and qemu-x86_64.

  Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
  Tested-by: Anders Roxell <anders.roxell@linaro.org>

Please refer to the following link for details of testing.
  https://qa-reports.linaro.org/~anders.roxell/linux-mainline-patches/build/linux-kbuild_masahiroy-branch-kbuild-20230124/?failures_only=false&results_layout=table#!#test-results

metadata:
  git_describe : v6.2-rc5-46-ga778c9dd138b
  git_repo : https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git
  git_sha : a778c9dd138b4f4410779705b444d58ce6f8fc44
  git_short_log : a778c9dd138b ("builddeb: clean generated package content")

--
Linaro LKFT
https://lkft.linaro.org

>
> Cheers,
> Nathan