Re: [PATCH] ltp: set -fomit-frame-pointer explicitly

["Yu, Mingli" <mingli.yu@windriver.com>]

On 2018年06月15日 03:20, Andre McCurdy wrote:
> On Thu, Jun 14, 2018 at 9:38 AM, Khem Raj <raj.khem@gmail.com> wrote:
>> On 6/14/18 2:35 AM, mingli.yu@windriver.com wrote:
>>> From: Mingli Yu <Mingli.Yu@windriver.com>
>>>
>>> When build ltp with -fno-omit-frame-pointer,
>>> it will trigger below error:
>>> | cve-2015-3290.c: In function 'child_thread':
>>> | cve-2015-3290.c:416:1: error: bp cannot be used in asm here
>>>
>>> And there is also some comment as below in the source
>>> file ltp/20180515-r0/git/testcases/cve/cve-2015-3290.c
>>> * Build with -O2.  Don't use -fno-omit-frame-pointer.
>>>
>>> So explicitly set -fomit-frame-pointer for compiler
>>> to fix the above build error.
>>>
>>> Signed-off-by: Mingli Yu <Mingli.Yu@windriver.com>
>>> ---
>>>   meta/recipes-extended/ltp/ltp_20180515.bb | 4 ++++
>>>   1 file changed, 4 insertions(+)
>>>
>>> diff --git a/meta/recipes-extended/ltp/ltp_20180515.bb b/meta/recipes-extended/ltp/ltp_20180515.bb
>>> index b07c1b9..5ec25ed 100644
>>> --- a/meta/recipes-extended/ltp/ltp_20180515.bb
>>> +++ b/meta/recipes-extended/ltp/ltp_20180515.bb
>>> @@ -19,6 +19,10 @@ LIC_FILES_CHKSUM = "\
>>>   DEPENDS = "attr libaio libcap acl openssl zip-native"
>>>   DEPENDS_append_libc-musl = " fts "
>>>   EXTRA_OEMAKE_append_libc-musl = " LIBC=musl "
>>> +
>>> +# -fomit-frame-pointer to handle cases where optimisation is set to -O0 or frame
>>> +# pointers have been enabled by -fno-omit-frame-pointer earlier in CFLAGS, etc.
>>> +CFLAGS_append = " ${@bb.utils.contains('SELECTED_OPTIMIZATION', '-fno-omit-frame-pointer', '-fomit-frame-pointer', '', d)}"
>
> This doesn't cover all cases - there may be times when the compiler
> chooses to enable frame pointers without being called with
> -fno-omit-frame-pointer.
>
> You could make the append conditional on x86 though (based on the
> error message, it's the x86 frame pointer register which is being used
> by inline assembler).

Thanks Khem and Andre!

Considering it's x86-64 specific(x86 actually not affected), I will 
update the logic unconditionally in V2 as below only for x86-64 to cover 
some cases when the compiler enables frame pointers without being called 
with -fno-omit-frame-pointer.

CFLAGS_append_x86-64 = " -fomit-frame-pointer"

Thanks,

>
>> may be just append it unconditionally, what do we lose ?
>> CFLAGS += "-fomit-frame-pointer"
>>
>>>   CFLAGS_append_powerpc64 = " -D__SANE_USERSPACE_TYPES__"
>>>   CFLAGS_append_mipsarchn64 = " -D__SANE_USERSPACE_TYPES__"
>>>   SRCREV = "96cbf48313afa65ef4d693d3441cbfd60a8d9b27"
>>>
>>
>>
>>
>> --
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