From mboxrd@z Thu Jan  1 00:00:00 1970
From: Markos Chandras <mchandras@suse.de>
Subject: Re: [PATCH] mk: toolchain: gcc: query the compiler
 macros to obtain the gcc version
Date: Tue, 22 Mar 2016 22:50:08 +0000
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To: Thomas Monjalon <thomas.monjalon@6wind.com>
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Hi,

On 22/03/16 22:34, Thomas Monjalon wrote:
> 2016-03-22 17:13, Markos Chandras:
>> This is similar to what's being used in the Linux kernel. Querying the
>> GCC macros directly gives more accurate results compared to -dumpversi=
on
>> which could vary across distributions.
>>
>> Signed-off-by: Markos Chandras <mchandras@suse.de>
>> ---
>> In openSUSE Tumbleweed (and in any other SUSE distribution which
>> uses (or will use) gcc >=3D 5), gcc -dumpversion returns '5'. This is =
on
>> purpose as discussed in https://bugzilla.opensuse.org/show_bug.cgi?id=3D=
941428
>=20
> Good to know. It could be in the commit log.

I can add this information to the commit message and send a v2 if needed.

>=20
>> -GCC_VERSION =3D $(subst .,,$(shell $(CC) -dumpversion | cut -f1-2 -d.=
))
>> +GCC_MAJOR =3D $(shell echo __GNUC__ | $(CC) -E -x c - | tail -n 1)
>> +GCC_MINOR =3D $(shell echo __GNUC_MINOR__ | $(CC) -E -x c - | tail -n=
 1)
>> +GCC_VERSION =3D $(GCC_MAJOR)$(GCC_MINOR)
>=20
> Are we sure the minor will always be only one digit?
>=20

Well, I can't be sure but minor has always been a single digit since gcc
>=3D 3 if I am not mistaken. But does it matter? What if it is two or mor=
e
digits? The previous code did something similar so if you had gcc
5.12.34 installed (and lets assume this is what is being returned by
-dumpversion), it would have returned 512. The comparison would still
work as it is at the moment no?

--=20
markos