Re: [RFC PATCH v2] MIPS: Kconfig: Select ARCH_WANT_FRAME_POINTERS

2020-11-16 Thread Tiezhu Yang 

On 11/16/2020 11:14 PM, Thomas Bogendoerfer wrote:

On Mon, Nov 16, 2020 at 05:55:06PM +0800, Tiezhu Yang wrote:

Select ARCH_WANT_FRAME_POINTERS to fix the following build error under
CONFIG_DEBUG_ATOMIC_SLEEP:

   CC  arch/mips/kernel/signal.o
{standard input}: Assembler messages:
{standard input}:1775: Error: Unable to parse register name $fp
scripts/Makefile.build:283: recipe for target 'arch/mips/kernel/signal.o' failed
make[2]: *** [arch/mips/kernel/signal.o] Error 1
scripts/Makefile.build:500: recipe for target 'arch/mips/kernel' failed
make[1]: *** [arch/mips/kernel] Error 2
Makefile:1799: recipe for target 'arch/mips' failed
make: *** [arch/mips] Error 2

I don't see this error and to me it looks strange to fix that with
enablding frame pointers... What gcc is this ?


I found this build error used with gcc 4.9.4.
I try it used with gcc 7.3.1 and it has no problem.
We can use new gcc version to avoid this build error.

Additionally, I want to know whether ARCH_WANT_FRAME_POINTERS
is necessary for MIPS to get more debugging info, with this
config we can enable the config FRAME_POINTER by default and
disable it manually.

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Makefile#n790
ifdef CONFIG_FRAME_POINTER
KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls

Thanks,
Tiezhu

Re: [RFC PATCH v2] MIPS: Kconfig: Select ARCH_WANT_FRAME_POINTERS

2020-11-16 Thread Thomas Bogendoerfer 
On Mon, Nov 16, 2020 at 05:55:06PM +0800, Tiezhu Yang wrote:
> Select ARCH_WANT_FRAME_POINTERS to fix the following build error under
> CONFIG_DEBUG_ATOMIC_SLEEP:
> 
>   CC  arch/mips/kernel/signal.o
> {standard input}: Assembler messages:
> {standard input}:1775: Error: Unable to parse register name $fp
> scripts/Makefile.build:283: recipe for target 'arch/mips/kernel/signal.o' 
> failed
> make[2]: *** [arch/mips/kernel/signal.o] Error 1
> scripts/Makefile.build:500: recipe for target 'arch/mips/kernel' failed
> make[1]: *** [arch/mips/kernel] Error 2
> Makefile:1799: recipe for target 'arch/mips' failed
> make: *** [arch/mips] Error 2

I don't see this error and to me it looks strange to fix that with
enablding frame pointers... What gcc is this ?

Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
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