diff mbox series

[v3] riscv: Handle zicsr/zifencei issue between gcc and binutils

Message ID 20230731095936.23397-1-xingmingzheng@iscas.ac.cn (mailing list archive)
State Superseded
Headers show
Series [v3] riscv: Handle zicsr/zifencei issue between gcc and binutils | expand

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Commit Message

Mingzheng Xing July 31, 2023, 9:59 a.m. UTC
Binutils-2.38 and GCC-12.1.0 bumped[0][1] the default ISA spec to the newer
20191213 version which moves some instructions from the I extension to the
Zicsr and Zifencei extensions. So if one of the binutils and GCC exceeds
that version, we should explicitly specifying Zicsr and Zifencei via -march
to cope with the new changes. but this only occurs when binutils >= 2.36
and GCC >= 11.1.0. It's a different story when binutils < 2.36.

binutils-2.36 supports the Zifencei extension[2] and splits Zifencei and
Zicsr from I[3]. GCC-11.1.0 is particular[4] because it add support Zicsr
and Zifencei extension for -march. binutils-2.35 does not support the
Zifencei extension, and does not need to specify Zicsr and Zifencei when
working with GCC >= 12.1.0.

To make our lives easier, let's relax the check to binutils >= 2.36 in
CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. For the other two cases,
where clang < 17 or GCC < 11.1.0, we will deal with them in
CONFIG_TOOLCHAIN_NEEDS_OLD_ISA_SPEC.

For more information, please refer to:
commit 6df2a016c0c8 ("riscv: fix build with binutils 2.38")
commit e89c2e815e76 ("riscv: Handle zicsr/zifencei issues between clang and binutils")
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc [0]
Link: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd [1]
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=5a1b31e1e1cee6e9f1c92abff59cdcfff0dddf30 [2]
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=729a53530e86972d1143553a415db34e6e01d5d2 [3]
Link: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=b03be74bad08c382da47e048007a78fa3fb4ef49 [4]
Link: https://lore.kernel.org/all/20230308220842.1231003-1-conor@kernel.org
Link: https://lore.kernel.org/all/20230223220546.52879-1-conor@kernel.org
Signed-off-by: Mingzheng Xing <xingmingzheng@iscas.ac.cn>
---

v3:
- Relax the check to binutils >= 2.36.
- Update the Kconfig help text and commit message.

v2:
- Update the Kconfig help text and commit message.
- Add considerations for low version gcc case.

 arch/riscv/Kconfig                     | 33 ++++++++++++++++----------
 arch/riscv/kernel/compat_vdso/Makefile |  8 ++++++-
 2 files changed, 27 insertions(+), 14 deletions(-)

Comments

Conor Dooley July 31, 2023, 2:01 p.m. UTC | #1
Hey,

On Mon, Jul 31, 2023 at 05:59:36PM +0800, Mingzheng Xing wrote:
> Binutils-2.38 and GCC-12.1.0 bumped[0][1] the default ISA spec to the newer
> 20191213 version which moves some instructions from the I extension to the
> Zicsr and Zifencei extensions. So if one of the binutils and GCC exceeds
> that version, we should explicitly specifying Zicsr and Zifencei via -march
> to cope with the new changes. but this only occurs when binutils >= 2.36
> and GCC >= 11.1.0. It's a different story when binutils < 2.36.
> 
> binutils-2.36 supports the Zifencei extension[2] and splits Zifencei and
> Zicsr from I[3]. GCC-11.1.0 is particular[4] because it add support Zicsr
> and Zifencei extension for -march. binutils-2.35 does not support the
> Zifencei extension, and does not need to specify Zicsr and Zifencei when
> working with GCC >= 12.1.0.
> 
> To make our lives easier, let's relax the check to binutils >= 2.36 in
> CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. For the other two cases,
> where clang < 17 or GCC < 11.1.0, we will deal with them in
> CONFIG_TOOLCHAIN_NEEDS_OLD_ISA_SPEC.
> 
> For more information, please refer to:
> commit 6df2a016c0c8 ("riscv: fix build with binutils 2.38")
> commit e89c2e815e76 ("riscv: Handle zicsr/zifencei issues between clang and binutils")
> Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc [0]
> Link: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd [1]
> Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=5a1b31e1e1cee6e9f1c92abff59cdcfff0dddf30 [2]
> Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=729a53530e86972d1143553a415db34e6e01d5d2 [3]
> Link: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=b03be74bad08c382da47e048007a78fa3fb4ef49 [4]
> Link: https://lore.kernel.org/all/20230308220842.1231003-1-conor@kernel.org
> Link: https://lore.kernel.org/all/20230223220546.52879-1-conor@kernel.org
> Signed-off-by: Mingzheng Xing <xingmingzheng@iscas.ac.cn>

You need to actually put the CC: stable@vger.kernel.org into the commit
message for the stable folks to pick things up.

> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 4c07b9189c86..2704bd91dfb5 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -570,24 +570,31 @@ config TOOLCHAIN_HAS_ZIHINTPAUSE
>  config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
>  	def_bool y
>  	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
> -	depends on AS_IS_GNU && AS_VERSION >= 23800
> -	help
> -	  Newer binutils versions default to ISA spec version 20191213 which
> -	  moves some instructions from the I extension to the Zicsr and Zifencei
> -	  extensions.
> +	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd
> +	depends on AS_IS_GNU && AS_VERSION >= 23600
> +	help
> +	  Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
> +	  20191213 version, which moves some instructions from the I extension to
> +	  the Zicsr and Zifencei extensions. This requires explicitly specifying
> +	  zicsr and zifencei when binutils >= 2.38 or GCC >= 12.1.0,

> but this only
> +	  occurs when binutils >= 2.36 and GCC >= 11.1.0.
> +	 It's a different story when binutils < 2.36.

I would replace this with something like:
	Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
	20191213 version, which moves some instructions from the I extension to
	the Zicsr and Zifencei extensions. This requires explicitly specifying
	zicsr and zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr
	and Zifencei are supported in binutils from version 2.36 onwards.
	To make life easier, and avoid forcing toolchains that default to a
	newer ISA spec to version 2.2, relax the check to binutils >= 2.36.
	For clang < 17 or GCC < 11.1.0, for which this is not possible, this is
	dealt with in CONFIG_TOOLCHAIN_NEEDS_OLD_ISA_SPEC.

I tried to take the personification out of it & hopefully made it a
little clearer what dropping the check to 2.36 does for us.

> Also, we have to consider the case of clang paired with binutils.

I think this sentence can go, its covered in the other config text.

I'm sorry for being a bit of a pedant about this, but this has been such
a can of worms that I would like things to remain explained well enough
that the text is sufficient next time a revisit is required.

Thanks,
Conor.

> +	  To make our lives easier, we relax the check to binutils >= 2.36. >  
>  config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
>  	def_bool y
>  	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
>  	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
> -	depends on CC_IS_CLANG && CLANG_VERSION < 170000
> -	help
> -	  Certain versions of clang do not support zicsr and zifencei via -march
> -	  but newer versions of binutils require it for the reasons noted in the
> -	  help text of CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. This
> -	  option causes an older ISA spec compatible with these older versions
> -	  of clang to be passed to GAS, which has the same result as passing zicsr
> -	  and zifencei to -march.
> +	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=b03be74bad08c382da47e048007a78fa3fb4ef49
> +	depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110100)
> +	help
> +	  Certain versions of clang and GCC do not support zicsr and zifencei via
> +	  -march. This option causes an older ISA spec compatible with these older
> +	  versions of clang and GCC to be passed to GAS, which has the same result
> +	  as passing zicsr and zifencei to -march.
>  
>  config FPU
>  	bool "FPU support"
> diff --git a/arch/riscv/kernel/compat_vdso/Makefile b/arch/riscv/kernel/compat_vdso/Makefile
> index 189345773e7e..b86e5e2c3aea 100644
> --- a/arch/riscv/kernel/compat_vdso/Makefile
> +++ b/arch/riscv/kernel/compat_vdso/Makefile
> @@ -11,7 +11,13 @@ compat_vdso-syms += flush_icache
>  COMPAT_CC := $(CC)
>  COMPAT_LD := $(LD)
>  
> -COMPAT_CC_FLAGS := -march=rv32g -mabi=ilp32
> +# binutils 2.35 does not support the zifencei extension, but in the ISA
> +# spec 20191213, G stands for IMAFD_ZICSR_ZIFENCEI.
> +ifdef CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
> +	COMPAT_CC_FLAGS := -march=rv32g -mabi=ilp32
> +else
> +	COMPAT_CC_FLAGS := -march=rv32imafd -mabi=ilp32
> +endif
>  COMPAT_LD_FLAGS := -melf32lriscv
>  
>  # Disable attributes, as they're useless and break the build.
> -- 
> 2.34.1
>
Mingzheng Xing July 31, 2023, 3:16 p.m. UTC | #2
On 7/31/23 22:01, Conor Dooley wrote:
> Hey,
>
> On Mon, Jul 31, 2023 at 05:59:36PM +0800, Mingzheng Xing wrote:
>> Binutils-2.38 and GCC-12.1.0 bumped[0][1] the default ISA spec to the newer
>> 20191213 version which moves some instructions from the I extension to the
>> Zicsr and Zifencei extensions. So if one of the binutils and GCC exceeds
>> that version, we should explicitly specifying Zicsr and Zifencei via -march
>> to cope with the new changes. but this only occurs when binutils >= 2.36
>> and GCC >= 11.1.0. It's a different story when binutils < 2.36.
>>
>> binutils-2.36 supports the Zifencei extension[2] and splits Zifencei and
>> Zicsr from I[3]. GCC-11.1.0 is particular[4] because it add support Zicsr
>> and Zifencei extension for -march. binutils-2.35 does not support the
>> Zifencei extension, and does not need to specify Zicsr and Zifencei when
>> working with GCC >= 12.1.0.
>>
>> To make our lives easier, let's relax the check to binutils >= 2.36 in
>> CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. For the other two cases,
>> where clang < 17 or GCC < 11.1.0, we will deal with them in
>> CONFIG_TOOLCHAIN_NEEDS_OLD_ISA_SPEC.
>>
>> For more information, please refer to:
>> commit 6df2a016c0c8 ("riscv: fix build with binutils 2.38")
>> commit e89c2e815e76 ("riscv: Handle zicsr/zifencei issues between clang and binutils")
>> Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc [0]
>> Link: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd [1]
>> Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=5a1b31e1e1cee6e9f1c92abff59cdcfff0dddf30 [2]
>> Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=729a53530e86972d1143553a415db34e6e01d5d2 [3]
>> Link: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=b03be74bad08c382da47e048007a78fa3fb4ef49 [4]
>> Link: https://lore.kernel.org/all/20230308220842.1231003-1-conor@kernel.org
>> Link: https://lore.kernel.org/all/20230223220546.52879-1-conor@kernel.org
>> Signed-off-by: Mingzheng Xing <xingmingzheng@iscas.ac.cn>
> You need to actually put the CC: stable@vger.kernel.org into the commit
> message for the stable folks to pick things up.

Thanks. Fixed in next version.

>> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
>> index 4c07b9189c86..2704bd91dfb5 100644
>> --- a/arch/riscv/Kconfig
>> +++ b/arch/riscv/Kconfig
>> @@ -570,24 +570,31 @@ config TOOLCHAIN_HAS_ZIHINTPAUSE
>>   config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
>>   	def_bool y
>>   	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
>> -	depends on AS_IS_GNU && AS_VERSION >= 23800
>> -	help
>> -	  Newer binutils versions default to ISA spec version 20191213 which
>> -	  moves some instructions from the I extension to the Zicsr and Zifencei
>> -	  extensions.
>> +	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd
>> +	depends on AS_IS_GNU && AS_VERSION >= 23600
>> +	help
>> +	  Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
>> +	  20191213 version, which moves some instructions from the I extension to
>> +	  the Zicsr and Zifencei extensions. This requires explicitly specifying
>> +	  zicsr and zifencei when binutils >= 2.38 or GCC >= 12.1.0,
>> but this only
>> +	  occurs when binutils >= 2.36 and GCC >= 11.1.0.
>> +	 It's a different story when binutils < 2.36.
> I would replace this with something like:
> 	Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
> 	20191213 version, which moves some instructions from the I extension to
> 	the Zicsr and Zifencei extensions. This requires explicitly specifying
> 	zicsr and zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr
> 	and Zifencei are supported in binutils from version 2.36 onwards.
> 	To make life easier, and avoid forcing toolchains that default to a
> 	newer ISA spec to version 2.2, relax the check to binutils >= 2.36.
> 	For clang < 17 or GCC < 11.1.0, for which this is not possible, this is
> 	dealt with in CONFIG_TOOLCHAIN_NEEDS_OLD_ISA_SPEC.
>
> I tried to take the personification out of it & hopefully made it a
> little clearer what dropping the check to 2.36 does for us.
>
>> Also, we have to consider the case of clang paired with binutils.
> I think this sentence can go, its covered in the other config text.
>
> I'm sorry for being a bit of a pedant about this, but this has been such
> a can of worms that I would like things to remain explained well enough
> that the text is sufficient next time a revisit is required.

Thanks for your review, I've made the changes and submitted a
new PATCH but there seems to be an email thread issue,
hopefully it won't have an effect, sorry about that.

:)
Thanks,
Mingzheng.

>
> Thanks,
> Conor.
>
>> +	  To make our lives easier, we relax the check to binutils >= 2.36. >
>>   config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
>>   	def_bool y
>>   	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
>>   	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
>> -	depends on CC_IS_CLANG && CLANG_VERSION < 170000
>> -	help
>> -	  Certain versions of clang do not support zicsr and zifencei via -march
>> -	  but newer versions of binutils require it for the reasons noted in the
>> -	  help text of CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. This
>> -	  option causes an older ISA spec compatible with these older versions
>> -	  of clang to be passed to GAS, which has the same result as passing zicsr
>> -	  and zifencei to -march.
>> +	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=b03be74bad08c382da47e048007a78fa3fb4ef49
>> +	depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110100)
>> +	help
>> +	  Certain versions of clang and GCC do not support zicsr and zifencei via
>> +	  -march. This option causes an older ISA spec compatible with these older
>> +	  versions of clang and GCC to be passed to GAS, which has the same result
>> +	  as passing zicsr and zifencei to -march.
>>   
>>   config FPU
>>   	bool "FPU support"
>> diff --git a/arch/riscv/kernel/compat_vdso/Makefile b/arch/riscv/kernel/compat_vdso/Makefile
>> index 189345773e7e..b86e5e2c3aea 100644
>> --- a/arch/riscv/kernel/compat_vdso/Makefile
>> +++ b/arch/riscv/kernel/compat_vdso/Makefile
>> @@ -11,7 +11,13 @@ compat_vdso-syms += flush_icache
>>   COMPAT_CC := $(CC)
>>   COMPAT_LD := $(LD)
>>   
>> -COMPAT_CC_FLAGS := -march=rv32g -mabi=ilp32
>> +# binutils 2.35 does not support the zifencei extension, but in the ISA
>> +# spec 20191213, G stands for IMAFD_ZICSR_ZIFENCEI.
>> +ifdef CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
>> +	COMPAT_CC_FLAGS := -march=rv32g -mabi=ilp32
>> +else
>> +	COMPAT_CC_FLAGS := -march=rv32imafd -mabi=ilp32
>> +endif
>>   COMPAT_LD_FLAGS := -melf32lriscv
>>   
>>   # Disable attributes, as they're useless and break the build.
>> -- 
>> 2.34.1
>>
>>
>> _______________________________________________
>> linux-riscv mailing list
>> linux-riscv@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-riscv
Conor Dooley July 31, 2023, 3:18 p.m. UTC | #3
On Mon, Jul 31, 2023 at 11:16:14PM +0800, Mingzheng Xing wrote:
> 
> Thanks for your review, I've made the changes and submitted a
> new PATCH but there seems to be an email thread issue,
> hopefully it won't have an effect, sorry about that.

Is there? It seemed fine to me, apart from the missing v4, was about to
take a look.
diff mbox series

Patch

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 4c07b9189c86..2704bd91dfb5 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -570,24 +570,31 @@  config TOOLCHAIN_HAS_ZIHINTPAUSE
 config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
 	def_bool y
 	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
-	depends on AS_IS_GNU && AS_VERSION >= 23800
-	help
-	  Newer binutils versions default to ISA spec version 20191213 which
-	  moves some instructions from the I extension to the Zicsr and Zifencei
-	  extensions.
+	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd
+	depends on AS_IS_GNU && AS_VERSION >= 23600
+	help
+	  Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
+	  20191213 version, which moves some instructions from the I extension to
+	  the Zicsr and Zifencei extensions. This requires explicitly specifying
+	  zicsr and zifencei when binutils >= 2.38 or GCC >= 12.1.0, but this only
+	  occurs when binutils >= 2.36 and GCC >= 11.1.0. It's a different story
+	  when binutils < 2.36. Also, we have to consider the case of clang paired
+	  with binutils.
+	  To make our lives easier, we relax the check to binutils >= 2.36. For
+	  the other two cases, where clang < 17 or GCC < 11.1.0, we will deal with
+	  them in CONFIG_TOOLCHAIN_NEEDS_OLD_ISA_SPEC.
 
 config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
 	def_bool y
 	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
 	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
-	depends on CC_IS_CLANG && CLANG_VERSION < 170000
-	help
-	  Certain versions of clang do not support zicsr and zifencei via -march
-	  but newer versions of binutils require it for the reasons noted in the
-	  help text of CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. This
-	  option causes an older ISA spec compatible with these older versions
-	  of clang to be passed to GAS, which has the same result as passing zicsr
-	  and zifencei to -march.
+	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=b03be74bad08c382da47e048007a78fa3fb4ef49
+	depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110100)
+	help
+	  Certain versions of clang and GCC do not support zicsr and zifencei via
+	  -march. This option causes an older ISA spec compatible with these older
+	  versions of clang and GCC to be passed to GAS, which has the same result
+	  as passing zicsr and zifencei to -march.
 
 config FPU
 	bool "FPU support"
diff --git a/arch/riscv/kernel/compat_vdso/Makefile b/arch/riscv/kernel/compat_vdso/Makefile
index 189345773e7e..b86e5e2c3aea 100644
--- a/arch/riscv/kernel/compat_vdso/Makefile
+++ b/arch/riscv/kernel/compat_vdso/Makefile
@@ -11,7 +11,13 @@  compat_vdso-syms += flush_icache
 COMPAT_CC := $(CC)
 COMPAT_LD := $(LD)
 
-COMPAT_CC_FLAGS := -march=rv32g -mabi=ilp32
+# binutils 2.35 does not support the zifencei extension, but in the ISA
+# spec 20191213, G stands for IMAFD_ZICSR_ZIFENCEI.
+ifdef CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
+	COMPAT_CC_FLAGS := -march=rv32g -mabi=ilp32
+else
+	COMPAT_CC_FLAGS := -march=rv32imafd -mabi=ilp32
+endif
 COMPAT_LD_FLAGS := -melf32lriscv
 
 # Disable attributes, as they're useless and break the build.