[U-Boot] [RFC V1] arm: config: enforce -fno-pic for gcc
Android's tool chain enable the -mandroid at default. This option will enable the -fpic, which cause uboot compilation failure: " LD u-boot u-boot contains unexpected relocations: R_ARM_ABS32 R_ARM_RELATIVE "
In my testcase, arm-linux-androideabi-gcc-4.9 internally enables '-fpic', so when compiling code, there will be relocation entries using type R_ARM_GOT_BREL and .got section. When linking all the built-in.o using ld, there will be R_ARM_ABS32 relocation entry and .got section in the final u-boot elf image. This can not be handled by u-boot, since u-boot only expects R_ARM_RELATIVE relocation entry. arm-poky-linux-gnueabi-gcc-4.9 default does not enable '-fpic', so there is not .got section and R_ARM_GOT_BREL in built-in.o. And in the final u-boot elf image, all relocation entries are R_ARM_RELATIVE.
we can pass '-fno-pic' to xxx-gcc to disable pic. whether the toolchain internally enables or disables pic, '-fno-pic' can work well.
Signed-off-by: Peng Fan Peng.Fan@freescale.com Cc: Albert Aribaud albert.u.boot@aribaud.net --- arch/arm/config.mk | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/arm/config.mk b/arch/arm/config.mk index 0550225..2b6322a 100644 --- a/arch/arm/config.mk +++ b/arch/arm/config.mk @@ -106,6 +106,7 @@ ALL-y += checkarmreloc # instruction. Relocation is not supported for that case, so disable # such usage by requiring word relocations. PLATFORM_CPPFLAGS += $(call cc-option, -mword-relocations) +PLATFORM_CPPFLAGS += $(call cc-option, -fno-pic) endif
# limit ourselves to the sections we want in the .bin.
Hi Albert,
Do you have any comments on this patch?
Regards, Peng.
On Sat, Dec 05, 2015 at 03:53:46PM +0800, Peng Fan wrote:
Android's tool chain enable the -mandroid at default. This option will enable the -fpic, which cause uboot compilation failure: " LD u-boot u-boot contains unexpected relocations: R_ARM_ABS32 R_ARM_RELATIVE "
In my testcase, arm-linux-androideabi-gcc-4.9 internally enables '-fpic', so when compiling code, there will be relocation entries using type R_ARM_GOT_BREL and .got section. When linking all the built-in.o using ld, there will be R_ARM_ABS32 relocation entry and .got section in the final u-boot elf image. This can not be handled by u-boot, since u-boot only expects R_ARM_RELATIVE relocation entry. arm-poky-linux-gnueabi-gcc-4.9 default does not enable '-fpic', so there is not .got section and R_ARM_GOT_BREL in built-in.o. And in the final u-boot elf image, all relocation entries are R_ARM_RELATIVE.
we can pass '-fno-pic' to xxx-gcc to disable pic. whether the toolchain internally enables or disables pic, '-fno-pic' can work well.
Signed-off-by: Peng Fan Peng.Fan@freescale.com Cc: Albert Aribaud albert.u.boot@aribaud.net
arch/arm/config.mk | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/arm/config.mk b/arch/arm/config.mk index 0550225..2b6322a 100644 --- a/arch/arm/config.mk +++ b/arch/arm/config.mk @@ -106,6 +106,7 @@ ALL-y += checkarmreloc # instruction. Relocation is not supported for that case, so disable # such usage by requiring word relocations. PLATFORM_CPPFLAGS += $(call cc-option, -mword-relocations) +PLATFORM_CPPFLAGS += $(call cc-option, -fno-pic) endif
# limit ourselves to the sections we want in the .bin.
2.6.2
--
Hi Albert,
Gentle ping! Sorry for missing to mail you when I sent out the patch.
Thanks, Peng. On Mon, Dec 14, 2015 at 03:28:56PM +0800, Peng Fan wrote:
Hi Albert,
Do you have any comments on this patch?
Regards, Peng.
On Sat, Dec 05, 2015 at 03:53:46PM +0800, Peng Fan wrote:
Android's tool chain enable the -mandroid at default. This option will enable the -fpic, which cause uboot compilation failure: " LD u-boot u-boot contains unexpected relocations: R_ARM_ABS32 R_ARM_RELATIVE "
In my testcase, arm-linux-androideabi-gcc-4.9 internally enables '-fpic', so when compiling code, there will be relocation entries using type R_ARM_GOT_BREL and .got section. When linking all the built-in.o using ld, there will be R_ARM_ABS32 relocation entry and .got section in the final u-boot elf image. This can not be handled by u-boot, since u-boot only expects R_ARM_RELATIVE relocation entry. arm-poky-linux-gnueabi-gcc-4.9 default does not enable '-fpic', so there is not .got section and R_ARM_GOT_BREL in built-in.o. And in the final u-boot elf image, all relocation entries are R_ARM_RELATIVE.
we can pass '-fno-pic' to xxx-gcc to disable pic. whether the toolchain internally enables or disables pic, '-fno-pic' can work well.
Signed-off-by: Peng Fan Peng.Fan@freescale.com Cc: Albert Aribaud albert.u.boot@aribaud.net
arch/arm/config.mk | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/arm/config.mk b/arch/arm/config.mk index 0550225..2b6322a 100644 --- a/arch/arm/config.mk +++ b/arch/arm/config.mk @@ -106,6 +106,7 @@ ALL-y += checkarmreloc # instruction. Relocation is not supported for that case, so disable # such usage by requiring word relocations. PLATFORM_CPPFLAGS += $(call cc-option, -mword-relocations) +PLATFORM_CPPFLAGS += $(call cc-option, -fno-pic) endif
# limit ourselves to the sections we want in the .bin.
2.6.2
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Hello Peng,
On Sat, 5 Dec 2015 15:53:46 +0800, Peng Fan Peng.Fan@freescale.com wrote:
Android's tool chain enable the -mandroid at default. This option will enable the -fpic, which cause uboot compilation failure: " LD u-boot u-boot contains unexpected relocations: R_ARM_ABS32 R_ARM_RELATIVE "
Any idea why Android's toolchain has -fpic enabled?
we can pass '-fno-pic' to xxx-gcc to disable pic. whether the toolchain internally enables or disables pic, '-fno-pic' can work well.
No problem apparently with this RFC. If you submit a non-RFC patch I will apply it.
Amicalement,
participants (4)
-
Albert ARIBAUD -
Peng Fan -
Peng Fan -
Peng Fan