[PATCH] ld-version: fix it on Fedora

[PATCH] ld-version: fix it on Fedora

[Michael S. Tsirkin]

On Fedora 23, ld --version outputs:
GNU ld version 2.25-15.fc23

But ld-version.sh fails to parse this, so e.g.  mips build fails to
enable VDSO, printing a warning that binutils >= 2.24 is required.

To fix, teach ld-version to parse this format.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---

Which tree should this be merged through? Mine? MIPS?

 scripts/ld-version.sh | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/scripts/ld-version.sh b/scripts/ld-version.sh
index 198580d..25d23c8 100755
--- a/scripts/ld-version.sh
+++ b/scripts/ld-version.sh
@@ -2,6 +2,8 @@
 # extract linker version number from stdin and turn into single number
 	{
 	gsub(".*)", "");
+	gsub(".*version ", "");
+	gsub("-.*", "");
 	split($1,a, ".");
 	print a[1]*10000000 + a[2]*100000 + a[3]*10000 + a[4]*100 + a[5];
 	exit
-- 
MST

Re: [PATCH] ld-version: fix it on Fedora

[Ralf Baechle]

On Thu, Jan 07, 2016 at 07:55:24PM +0200, Michael S. Tsirkin wrote:

> On Fedora 23, ld --version outputs:
> GNU ld version 2.25-15.fc23
> 
> But ld-version.sh fails to parse this, so e.g.  mips build fails to
> enable VDSO, printing a warning that binutils >= 2.24 is required.
> 
> To fix, teach ld-version to parse this format.
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
> 
> Which tree should this be merged through? Mine? MIPS?

MIPS is the sole user of ld-ifversion at this time and taking this through
the MIPS tree will avoid possible merge conflicts with James Hogan's
pending d5ece1cb074b2c7082c9a2948ac598dd0ad40657 fix ("Fix ld-version.sh to
handle large 3rd version part").  So I think I should take this through
the MIPS tree.

Thanks!

  Ralf

Re: [PATCH] ld-version: fix it on Fedora

[Alexandre Oliva]

On Jan  7, 2016, "Michael S. Tsirkin" <mst@redhat.com> wrote:

> On Fedora 23, ld --version outputs:
> GNU ld version 2.25-15.fc23

> But ld-version.sh fails to parse this

On gnewsense 3, ld --version outputs:

GNU ld (GNU Binutils for Debian) 2.20.1-system.20100303
Copyright [...]

The date at the end severely confuses the version parser.

Furthermore, awk is mawk, whose gsub takes ')' as grouping, so it
complains about the missing '('.

Also, once a[1] is multiplied by 1e7, mawk's print spits out the number
in exponential notation, which confuses the -lt test.  In order to avoid
that falling back to floating-point numbers, I've used smaller
multipliers and concatenated (truncated) integers.  Yuck.

I've modified the script so that it takes the - as a separator too, and
so that it works on both gawk and mawk.  Here's the ld-version.sh that
worked for me.  I guess this will have to be combined with your patch
somehow.

#!/usr/bin/awk -f
# extract linker version number from stdin and turn into single number
        {
        gsub(".*[)]", "");
        split($1,a, "[-.]");
        printf "%i%04i\n", a[1]*10000 + a[2]*100 + a[3], (a[4]*100 + a[5])%10000;
        exit
        }

-- 
Alexandre Oliva, freedom fighter    http://FSFLA.org/~lxoliva/
You must be the change you wish to see in the world. -- Gandhi
Be Free! -- http://FSFLA.org/   FSF Latin America board member
Free Software Evangelist|Red Hat Brasil GNU Toolchain Engineer

Re: [PATCH] ld-version: fix it on Fedora

[James Hogan]

Cc'ing Daniel, who has hit further breakage due to unusual version numbers.

On 7 January 2016 at 17:55, Michael S. Tsirkin <mst@redhat.com> wrote:
> On Fedora 23, ld --version outputs:
> GNU ld version 2.25-15.fc23
>
> But ld-version.sh fails to parse this, so e.g.  mips build fails to
> enable VDSO, printing a warning that binutils >= 2.24 is required.
>
> To fix, teach ld-version to parse this format.
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>
> Which tree should this be merged through? Mine? MIPS?
>
>  scripts/ld-version.sh | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/scripts/ld-version.sh b/scripts/ld-version.sh
> index 198580d..25d23c8 100755
> --- a/scripts/ld-version.sh
> +++ b/scripts/ld-version.sh
> @@ -2,6 +2,8 @@
>  # extract linker version number from stdin and turn into single number
>         {
>         gsub(".*)", "");
> +       gsub(".*version ", "");
> +       gsub("-.*", "");
>         split($1,a, ".");
>         print a[1]*10000000 + a[2]*100000 + a[3]*10000 + a[4]*100 + a[5];
>         exit
> --
> MST
>

RE: [PATCH] ld-version: fix it on Fedora

[Daniel Sanders]

Hi,

The version number that's giving me problems is 2.24.51.20140217 which ld-version.sh converts to 2036931700 (20000000+2400000+510000+2014021700).

At the moment, I'm wondering whether we really need to handle more than three version number components. Another thought is that the comparison could be inside ld-version.sh (or a replacement) so that it can compare the array of version components directly instead of using a constructed integer as a proxy.

> -----Original Message-----
> From: james@albanarts.com [mailto:james@albanarts.com] On Behalf Of
> James Hogan
> Sent: 13 January 2016 17:06
> To: Michael S. Tsirkin
> Cc: LKML; Michal Marek; linux-kbuild@vger.kernel.org; Linux MIPS Mailing
> List; Ralf Baechle; Daniel Sanders
> Subject: Re: [PATCH] ld-version: fix it on Fedora
> 
> Cc'ing Daniel, who has hit further breakage due to unusual version numbers.
> 
> On 7 January 2016 at 17:55, Michael S. Tsirkin <mst@redhat.com> wrote:
> > On Fedora 23, ld --version outputs:
> > GNU ld version 2.25-15.fc23
> >
> > But ld-version.sh fails to parse this, so e.g.  mips build fails to
> > enable VDSO, printing a warning that binutils >= 2.24 is required.
> >
> > To fix, teach ld-version to parse this format.
> >
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> >
> > Which tree should this be merged through? Mine? MIPS?
> >
> >  scripts/ld-version.sh | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/scripts/ld-version.sh b/scripts/ld-version.sh
> > index 198580d..25d23c8 100755
> > --- a/scripts/ld-version.sh
> > +++ b/scripts/ld-version.sh
> > @@ -2,6 +2,8 @@
> >  # extract linker version number from stdin and turn into single number
> >         {
> >         gsub(".*)", "");
> > +       gsub(".*version ", "");
> > +       gsub("-.*", "");
> >         split($1,a, ".");
> >         print a[1]*10000000 + a[2]*100000 + a[3]*10000 + a[4]*100 + a[5];
> >         exit
> > --
> > MST
> >

RE: [PATCH] ld-version: fix it on Fedora

[Daniel Sanders]

> From: Alexander Kapshuk [alexander.kapshuk@gmail.com]
> Sent: 23 January 2016 14:41
> To: Daniel Sanders
> Cc: James Hogan; Michael S. Tsirkin; LKML; Michal Marek; linux-kbuild@vger.kernel.org; Linux MIPS Mailing List; Ralf Baechle
> Subject: Re: [PATCH] ld-version: fix it on Fedora
> 
> On Wed, Jan 13, 2016 at 7:30 PM, Daniel Sanders <Daniel.Sanders@imgtec.com<mailto:Daniel.Sanders@imgtec.com>> wrote:
> Hi,
> 
> The version number that's giving me problems is 2.24.51.20140217 which ld-version.sh converts to 2036931700 (20000000+2400000+510000+2014021700).
> 
> At the moment, I'm wondering whether we really need to handle more than three version number components. Another thought is that the comparison could be inside ld-version.sh (or a replacement) so that it can compare the array of version components directly instead of using a constructed integer as a proxy.
> 
> > -----Original Message-----
> > From: james@albanarts.com<mailto:james@albanarts.com> [mailto:james@albanarts.com<mailto:james@albanarts.com>] On Behalf Of
> > James Hogan
> > Sent: 13 January 2016 17:06
> > To: Michael S. Tsirkin
> > Cc: LKML; Michal Marek; linux-kbuild@vger.kernel.org<mailto:linux-kbuild@vger.kernel.org>; Linux MIPS Mailing
> > List; Ralf Baechle; Daniel Sanders
> > Subject: Re: [PATCH] ld-version: fix it on Fedora
> >
> > Cc'ing Daniel, who has hit further breakage due to unusual version numbers.
> >
> > On 7 January 2016 at 17:55, Michael S. Tsirkin <mst@redhat.com<mailto:mst@redhat.com>> wrote:
> > > On Fedora 23, ld --version outputs:
> > > GNU ld version 2.25-15.fc23
> > >
> > > But ld-version.sh fails to parse this, so e.g.  mips build fails to
> > > enable VDSO, printing a warning that binutils >= 2.24 is required.
> > >
> > > To fix, teach ld-version to parse this format.
> > >
> > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com<mailto:mst@redhat.com>>
> > > ---
> > >
> > > Which tree should this be merged through? Mine? MIPS?
> > >
> > >  scripts/ld-version.sh | 2 ++
> > >  1 file changed, 2 insertions(+)
> > >
> > > diff --git a/scripts/ld-version.sh b/scripts/ld-version.sh
> > > index 198580d..25d23c8 100755
> > > --- a/scripts/ld-version.sh
> > > +++ b/scripts/ld-version.sh
> > > @@ -2,6 +2,8 @@
> > >  # extract linker version number from stdin and turn into single number
> > >         {
> > >         gsub(".*)", "");
> > > +       gsub(".*version ", "");
> > > +       gsub("-.*", "");
> > >         split($1,a, ".");
> > >         print a[1]*10000000 + a[2]*100000 + a[3]*10000 + a[4]*100 + a[5];
> > >         exit
> > > --
> > > MST
> > >
> 
> Is this the output you're looking for?
> 
> % echo 'GNU ld version 2.25-15.fc23' |
> > awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> > match($0, /[0-9]+([.]?[0-9]+)+/)
> > bin=substr($0,RSTART,RLENGTH)
> > split(bin, a, ".")
> > print a[1]*10000000 + a[2]*100000 + a[3]*10000}'
> 22500000
> 
> % echo 2.25.1.20140217 |
> > awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> > match($0, /[0-9]+([.]?[0-9]+)+/)
> > bin=substr($0,RSTART,RLENGTH)
> > split(bin, a, ".")
> > print a[1]*10000000 + a[2]*100000 + a[3]*10000}'
> 22510000
> 
> awk parsing code taken from ver_linux:
> /usr/src/linux/scripts/ver_linux:28,33
> ld -v 2>&1 |
> awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
>     match($0, /[0-9]+([.]?[0-9]+)+/)
>     printf("Binutils\t\t%s\n",
>     substr($0,RSTART,RLENGTH))
> }'
> 

It's close. That code doesn't quite work for my version number because the third component has two
digits and overflows into the second component in the proxy integer:
$ echo 2.24.51.20140217 |
> awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> match($0, /[0-9]+([.]?[0-9]+)+/)
> bin=substr($0,RSTART,RLENGTH)
> split(bin, a, ".")
> print a[1]*10000000 + a[2]*100000 + a[3]*10000}'
22910000

but adding a zero to the first two scale factors, or removing one from the third works for me.
$ echo 2.24.51.20140217 | awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> match($0, /[0-9]+([.]?[0-9]+)+/)
> bin=substr($0,RSTART,RLENGTH)
> split(bin, a, ".")
> print a[1]*100000000 + a[2]*1000000 + a[3]*10000}'
224510000
$ echo 2.24.51.20140217 | awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> match($0, /[0-9]+([.]?[0-9]+)+/)
> bin=substr($0,RSTART,RLENGTH)
> split(bin, a, ".")
> print a[1]*10000000 + a[2]*100000 + a[3]*1000}'
22451000

RE: [PATCH] ld-version: fix it on Fedora

[Daniel Sanders]

> From: Alexander Kapshuk [alexander.kapshuk@gmail.com]
> Sent: 23 January 2016 14:41
> To: Daniel Sanders
> Cc: James Hogan; Michael S. Tsirkin; LKML; Michal Marek; linux-kbuild@vger.kernel.org; Linux MIPS Mailing List; Ralf Baechle
> Subject: Re: [PATCH] ld-version: fix it on Fedora
> 
> On Wed, Jan 13, 2016 at 7:30 PM, Daniel Sanders <Daniel.Sanders@imgtec.com<mailto:Daniel.Sanders@imgtec.com>> wrote:
> Hi,
> 
> The version number that's giving me problems is 2.24.51.20140217 which ld-version.sh converts to 2036931700 (20000000+2400000+510000+2014021700).
> 
> At the moment, I'm wondering whether we really need to handle more than three version number components. Another thought is that the comparison could be inside ld-version.sh (or a replacement) so that it can compare the array of version components directly instead of using a constructed integer as a proxy.
> 
> > -----Original Message-----
> > From: james@albanarts.com<mailto:james@albanarts.com> [mailto:james@albanarts.com<mailto:james@albanarts.com>] On Behalf Of
> > James Hogan
> > Sent: 13 January 2016 17:06
> > To: Michael S. Tsirkin
> > Cc: LKML; Michal Marek; linux-kbuild@vger.kernel.org<mailto:linux-kbuild@vger.kernel.org>; Linux MIPS Mailing
> > List; Ralf Baechle; Daniel Sanders
> > Subject: Re: [PATCH] ld-version: fix it on Fedora
> >
> > Cc'ing Daniel, who has hit further breakage due to unusual version numbers.
> >
> > On 7 January 2016 at 17:55, Michael S. Tsirkin <mst@redhat.com<mailto:mst@redhat.com>> wrote:
> > > On Fedora 23, ld --version outputs:
> > > GNU ld version 2.25-15.fc23
> > >
> > > But ld-version.sh fails to parse this, so e.g.  mips build fails to
> > > enable VDSO, printing a warning that binutils >= 2.24 is required.
> > >
> > > To fix, teach ld-version to parse this format.
> > >
> > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com<mailto:mst@redhat.com>>
> > > ---
> > >
> > > Which tree should this be merged through? Mine? MIPS?
> > >
> > >  scripts/ld-version.sh | 2 ++
> > >  1 file changed, 2 insertions(+)
> > >
> > > diff --git a/scripts/ld-version.sh b/scripts/ld-version.sh
> > > index 198580d..25d23c8 100755
> > > --- a/scripts/ld-version.sh
> > > +++ b/scripts/ld-version.sh
> > > @@ -2,6 +2,8 @@
> > >  # extract linker version number from stdin and turn into single number
> > >         {
> > >         gsub(".*)", "");
> > > +       gsub(".*version ", "");
> > > +       gsub("-.*", "");
> > >         split($1,a, ".");
> > >         print a[1]*10000000 + a[2]*100000 + a[3]*10000 + a[4]*100 + a[5];
> > >         exit
> > > --
> > > MST
> > >
> 
> Is this the output you're looking for?
> 
> % echo 'GNU ld version 2.25-15.fc23' |
> > awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> > match($0, /[0-9]+([.]?[0-9]+)+/)
> > bin=substr($0,RSTART,RLENGTH)
> > split(bin, a, ".")
> > print a[1]*10000000 + a[2]*100000 + a[3]*10000}'
> 22500000
> 
> % echo 2.25.1.20140217 |
> > awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> > match($0, /[0-9]+([.]?[0-9]+)+/)
> > bin=substr($0,RSTART,RLENGTH)
> > split(bin, a, ".")
> > print a[1]*10000000 + a[2]*100000 + a[3]*10000}'
> 22510000
> 
> awk parsing code taken from ver_linux:
> /usr/src/linux/scripts/ver_linux:28,33
> ld -v 2>&1 |
> awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
>     match($0, /[0-9]+([.]?[0-9]+)+/)
>     printf("Binutils\t\t%s\n",
>     substr($0,RSTART,RLENGTH))
> }'
> 

It's close. That code doesn't quite work for my version number because the third component has two
digits and overflows into the second component in the proxy integer:
$ echo 2.24.51.20140217 |
> awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> match($0, /[0-9]+([.]?[0-9]+)+/)
> bin=substr($0,RSTART,RLENGTH)
> split(bin, a, ".")
> print a[1]*10000000 + a[2]*100000 + a[3]*10000}'
22910000

but adding a zero to the first two scale factors, or removing one from the third works for me.
$ echo 2.24.51.20140217 | awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> match($0, /[0-9]+([.]?[0-9]+)+/)
> bin=substr($0,RSTART,RLENGTH)
> split(bin, a, ".")
> print a[1]*100000000 + a[2]*1000000 + a[3]*10000}'
224510000
$ echo 2.24.51.20140217 | awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> match($0, /[0-9]+([.]?[0-9]+)+/)
> bin=substr($0,RSTART,RLENGTH)
> split(bin, a, ".")
> print a[1]*10000000 + a[2]*100000 + a[3]*1000}'
22451000
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From:   Will Deacon <will.deacon@arm.com>
To:     "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc:     Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>,
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On Fri, Jan 15, 2016 at 11:28:45AM -0800, Paul E. McKenney wrote:
> On Fri, Jan 15, 2016 at 09:54:01AM -0800, Paul E. McKenney wrote:
> > On Fri, Jan 15, 2016 at 10:24:32AM +0000, Will Deacon wrote:
> > > See my earlier reply [1] (but also, your WRC Linux example looks more
> > > like a variant on WWC and I couldn't really follow it).
> > 
> > I will revisit my WRC Linux example.  And yes, creating litmus tests
> > that use non-fake dependencies is still a bit of an undertaking.  :-/
> > I am sure that it will seem more natural with time and experience...
> 
> Hmmm...  You are quite right, I did do WWC.  I need to change cpu2()'s
> last access from a store to a load to get WRC.  Plus the levels of
> indirection definitely didn't match up, did they?

Nope, it was pretty baffling!

> 	struct foo {
> 		struct foo *next;
> 	};
> 	struct foo a;
> 	struct foo b;
> 	struct foo c = { &a };
> 	struct foo d = { &b };
> 	struct foo x = { &c };
> 	struct foo y = { &d };
> 	struct foo *r1, *r2, *r3;
> 
> 	void cpu0(void)
> 	{
> 		WRITE_ONCE(x.next, &y);
> 	}
> 
> 	void cpu1(void)
> 	{
> 		r1 = lockless_dereference(x.next);
> 		WRITE_ONCE(r1->next, &x);
> 	}
> 
> 	void cpu2(void)
> 	{
> 		r2 = lockless_dereference(y.next);
> 		r3 = READ_ONCE(r2->next);
> 	}
> 
> In this case, it is legal to end the run with:
> 
> 	r1 == &y && r2 == &x && r3 == &c
> 
> Please see below for a ppcmem litmus test.
> 
> So, did I get it right this time?  ;-)

The code above looks correct to me (in that it matches WRC+addrs),
but your litmus test:

> PPC WRCnf+addrs
> ""
> {
> 0:r2=x; 0:r3=y;
> 1:r2=x; 1:r3=y;
> 2:r2=x; 2:r3=y;
> c=a; d=b; x=c; y=d;
> }
>  P0           | P1            | P2            ;
>  stw r3,0(r2) | lwz r8,0(r2)  | lwz r8,0(r3)  ;
>               | stw r2,0(r3)  | lwz r9,0(r8)  ;
> exists
> (1:r8=y /\ 2:r8=x /\ 2:r9=c)

Seems to be missing the address dependency on P1.

Will

Re: [PATCH] ld-version: fix it on Fedora

[Alexander Kapshuk]

On Mon, Jan 25, 2016 at 12:49 PM, Daniel Sanders
<Daniel.Sanders@imgtec.com> wrote:
>
> > From: Alexander Kapshuk [alexander.kapshuk@gmail.com]
> > Sent: 23 January 2016 14:41
> > To: Daniel Sanders
> > Cc: James Hogan; Michael S. Tsirkin; LKML; Michal Marek; linux-kbuild@vger.kernel.org; Linux MIPS Mailing List; Ralf Baechle
> > Subject: Re: [PATCH] ld-version: fix it on Fedora
> >
> > On Wed, Jan 13, 2016 at 7:30 PM, Daniel Sanders <Daniel.Sanders@imgtec.com<mailto:Daniel.Sanders@imgtec.com>> wrote:
> > Hi,
> >
> > The version number that's giving me problems is 2.24.51.20140217 which ld-version.sh converts to 2036931700 (20000000+2400000+510000+2014021700).
> >
> > At the moment, I'm wondering whether we really need to handle more than three version number components. Another thought is that the comparison could be inside ld-version.sh (or a replacement) so that it can compare the array of version components directly instead of using a constructed integer as a proxy.
> >
> > > -----Original Message-----
> > > From: james@albanarts.com<mailto:james@albanarts.com> [mailto:james@albanarts.com<mailto:james@albanarts.com>] On Behalf Of
> > > James Hogan
> > > Sent: 13 January 2016 17:06
> > > To: Michael S. Tsirkin
> > > Cc: LKML; Michal Marek; linux-kbuild@vger.kernel.org<mailto:linux-kbuild@vger.kernel.org>; Linux MIPS Mailing
> > > List; Ralf Baechle; Daniel Sanders
> > > Subject: Re: [PATCH] ld-version: fix it on Fedora
> > >
> > > Cc'ing Daniel, who has hit further breakage due to unusual version numbers.
> > >
> > > On 7 January 2016 at 17:55, Michael S. Tsirkin <mst@redhat.com<mailto:mst@redhat.com>> wrote:
> > > > On Fedora 23, ld --version outputs:
> > > > GNU ld version 2.25-15.fc23
> > > >
> > > > But ld-version.sh fails to parse this, so e.g.  mips build fails to
> > > > enable VDSO, printing a warning that binutils >= 2.24 is required.
> > > >
> > > > To fix, teach ld-version to parse this format.
> > > >
> > > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com<mailto:mst@redhat.com>>
> > > > ---
> > > >
> > > > Which tree should this be merged through? Mine? MIPS?
> > > >
> > > >  scripts/ld-version.sh | 2 ++
> > > >  1 file changed, 2 insertions(+)
> > > >
> > > > diff --git a/scripts/ld-version.sh b/scripts/ld-version.sh
> > > > index 198580d..25d23c8 100755
> > > > --- a/scripts/ld-version.sh
> > > > +++ b/scripts/ld-version.sh
> > > > @@ -2,6 +2,8 @@
> > > >  # extract linker version number from stdin and turn into single number
> > > >         {
> > > >         gsub(".*)", "");
> > > > +       gsub(".*version ", "");
> > > > +       gsub("-.*", "");
> > > >         split($1,a, ".");
> > > >         print a[1]*10000000 + a[2]*100000 + a[3]*10000 + a[4]*100 + a[5];
> > > >         exit
> > > > --
> > > > MST
> > > >
> >
> > Is this the output you're looking for?
> >
> > % echo 'GNU ld version 2.25-15.fc23' |
> > > awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> > > match($0, /[0-9]+([.]?[0-9]+)+/)
> > > bin=substr($0,RSTART,RLENGTH)
> > > split(bin, a, ".")
> > > print a[1]*10000000 + a[2]*100000 + a[3]*10000}'
> > 22500000
> >
> > % echo 2.25.1.20140217 |
> > > awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> > > match($0, /[0-9]+([.]?[0-9]+)+/)
> > > bin=substr($0,RSTART,RLENGTH)
> > > split(bin, a, ".")
> > > print a[1]*10000000 + a[2]*100000 + a[3]*10000}'
> > 22510000
> >
> > awk parsing code taken from ver_linux:
> > /usr/src/linux/scripts/ver_linux:28,33
> > ld -v 2>&1 |
> > awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> >     match($0, /[0-9]+([.]?[0-9]+)+/)
> >     printf("Binutils\t\t%s\n",
> >     substr($0,RSTART,RLENGTH))
> > }'
> >
>
> It's close. That code doesn't quite work for my version number because the third component has two
> digits and overflows into the second component in the proxy integer:
> $ echo 2.24.51.20140217 |
> > awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> > match($0, /[0-9]+([.]?[0-9]+)+/)
> > bin=substr($0,RSTART,RLENGTH)
> > split(bin, a, ".")
> > print a[1]*10000000 + a[2]*100000 + a[3]*10000}'
> 22910000
>
> but adding a zero to the first two scale factors, or removing one from the third works for me.
> $ echo 2.24.51.20140217 | awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> > match($0, /[0-9]+([.]?[0-9]+)+/)
> > bin=substr($0,RSTART,RLENGTH)
> > split(bin, a, ".")
> > print a[1]*100000000 + a[2]*1000000 + a[3]*10000}'
> 224510000
> $ echo 2.24.51.20140217 | awk '/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
> > match($0, /[0-9]+([.]?[0-9]+)+/)
> > bin=substr($0,RSTART,RLENGTH)
> > split(bin, a, ".")
> > print a[1]*10000000 + a[2]*100000 + a[3]*1000}'
> 22451000


I put the latter of the two methods that worked for you it into a
script, shown below:

#!/usr/bin/awk -f
# extract linker version number from stdin and turn into single number

/[0-9]+([.]?[0-9]+)+/ && !/not found$/{
    match($0, /[0-9]+([.]?[0-9]+)+/)
    ver=substr($0,RSTART,RLENGTH)
    split(ver, a, ".")
    print a[1]*10000000 + a[2]*100000 + a[3]*1000
    exit
}

And tried it out on the following input:

% echo 2.24.51.20140217 | ld-version.sh
22451000
% echo 'GNU ld version 2.25-15.fc23' | ld-version.sh
22500000

Re: [PATCH] ld-version: fix it on Fedora

[Maciej W. Rozycki]

On Mon, 25 Jan 2016, Alexander Kapshuk wrote:

> > > At the moment, I'm wondering whether we really need to handle more 
> > > than three version number components. Another thought is that the 
> > > comparison could be inside ld-version.sh (or a replacement) so that 
> > > it can compare the array of version components directly instead of 
> > > using a constructed integer as a proxy.

 I don't think going beyond three version number components makes sense, 
to be honest.  Any such numbers will be non-standard third-party releases.  
Upstream binutils use a three-component versioning scheme.  Even the third 
component only makes sense because sometime we may actually rely on a bug 
fix first available with a maintenance release; these reach single-digit 
numbers only and hardly ever above 1 actually as another base release is 
usually made quickly enough (the usual schedule was annual, although as 
from 2.26, out last Monday, it has been switched to a semi-annual cycle).

> I put the latter of the two methods that worked for you it into a
> script, shown below:
> 
> #!/usr/bin/awk -f
> # extract linker version number from stdin and turn into single number
> 
> /[0-9]+([.]?[0-9]+)+/ && !/not found$/{
>     match($0, /[0-9]+([.]?[0-9]+)+/)
>     ver=substr($0,RSTART,RLENGTH)
>     split(ver, a, ".")
>     print a[1]*10000000 + a[2]*100000 + a[3]*1000
>     exit
> }
> 
> And tried it out on the following input:
> 
> % echo 2.24.51.20140217 | ld-version.sh
> 22451000

 So the above version is a non-release snapshot from the development tree 
as the repository trunk is switched to x.y+1.51 once a release branch for 
x.y has been made.  Then the release branch is switched to x.y-1.90 for 
prereleases, before settling on x.y or x.y.0 (this hasn't been consistent) 
for the actual base release.  Any subsequent maintenance releases will 
then have their version set to x.y.1, x.y.2, and so on.  We shouldn't ever 
rely on versions that are not proper releases.

> % echo 'GNU ld version 2.25-15.fc23' | ld-version.sh
> 22500000

 So this is a base 2.25 release (obviously with vendor patches, hopefully 
not breaking what we might rely on).

 FWIW,

  Maciej

Re: [PATCH] ld-version: fix it on Fedora

[Maciej W. Rozycki]

On Sat, 30 Jan 2016, Maciej W. Rozycki wrote:

> > % echo 2.24.51.20140217 | ld-version.sh
> > 22451000
> 
>  So the above version is a non-release snapshot from the development tree 
> as the repository trunk is switched to x.y+1.51 once a release branch for 
> x.y has been made.  Then the release branch is switched to x.y-1.90 for 
> prereleases, before settling on x.y or x.y.0 (this hasn't been consistent) 
> for the actual base release.  Any subsequent maintenance releases will 
> then have their version set to x.y.1, x.y.2, and so on.  We shouldn't ever 
> rely on versions that are not proper releases.

 I need to correct myself here for unclear notation or off-by-one errors, 
the flow is of course as follows:

    trunk
   x.y-1.51
      |
      |
      |
release branchpoint
      |      \
    x.y.51 x.y-1.90
      |   prerelease
      |       |
      |       |
      v    x.y-1.91
      .   prerelease
      .       |
      .       |
              |
           x.y-1.92
          prerelease
              .
              .
              .
            x.y.0
         base release
              |
              |
              |
            x.y.1
      maintenance release
              |
              |
              |
            x.y.2
      maintenance release
              |
              v
              .
              .
              .

 The revision number is sometimes bumped up on trunk as well, to 52, 53, 
etc., though the criteria are not completely clear to me; perhaps to make 
a trunk snapshot "release".

 And last but not least for non-release builds the snapshot date is 
automatically appended to the version number reported, as seen above.

  Maciej

Re: [PATCH] ld-version: fix it on Fedora

[Maciej W. Rozycki]

On Thu, 7 Jan 2016, Ralf Baechle wrote:

> > GNU ld version 2.25-15.fc23
> > 
> > But ld-version.sh fails to parse this, so e.g.  mips build fails to
> > enable VDSO, printing a warning that binutils >= 2.24 is required.
> > 
> > To fix, teach ld-version to parse this format.
> > 
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> > 
> > Which tree should this be merged through? Mine? MIPS?
> 
> MIPS is the sole user of ld-ifversion at this time and taking this through
> the MIPS tree will avoid possible merge conflicts with James Hogan's
> pending d5ece1cb074b2c7082c9a2948ac598dd0ad40657 fix ("Fix ld-version.sh to
> handle large 3rd version part").  So I think I should take this through
> the MIPS tree.

 FYI, I'm still getting a failure here, with:

$ mips64el-linux-ld --version
GNU ld (GNU Binutils) 2.20.1.20100303
[...]
$

-- so this is a plain upstream development snapshot as these have their 
date appended.  Can we just get rid of the subversion components beyond 
the third, as I already suggested?  I.e. stop on the third point and in 
any case on a non-point-non-digit.

 I'll post a minimal fix shortly, feel free to enhance it if needed.

  Maciej