[PATCHv2] openocd: avoid documentation rebuild to fix build issues

On PowerPC64(le), we patch all configure scripts. Due to this, the
version.texi in OpenOCD files gets regenerated, and then since it has
a newer date than openocd.info, openocd build system rebuilds the
documentation. Unfortunately, this documentation rebuild fails on old
machines.

We work around this by faking the date of the generated version.texi
file, to make the build system believe the documentation doesn't need
to be regenerated.

Fixes:

  http://autobuild.buildroot.net/results/3cbe65a46e75b8e67846d593884c96df97dec7a4

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
Changes since v1: fix commit title

This is an alternative proposal to:

  https://patchwork.ozlabs.org/patch/724932/

and to:

  https://github.com/ntfreak/openocd/pull/4/commits/2c0cc66d5388e07679ac9f07c1ce0f8469931f02

which was submitted upstream but not accepted.
---
 package/openocd/openocd.mk | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

On Sun, Feb 26, 2017 at 11:22:16PM +0100, Thomas Petazzoni wrote:
> On PowerPC64(le), we patch all configure scripts. Due to this, the
> version.texi in OpenOCD files gets regenerated, and then since it has
> a newer date than openocd.info, openocd build system rebuilds the
> documentation. Unfortunately, this documentation rebuild fails on old
> machines.
> 
> We work around this by faking the date of the generated version.texi
> file, to make the build system believe the documentation doesn't need
> to be regenerated.

Looks good to me.

I just have a comment about your comment:

I don't think modifying the configure script is sufficient to cause
version.texi to be rebuilt, it just causes the timestamp file to be
checked. It's the timezone issue that actually causes the rebuild and it
happens even though version.texi isn't out of date. (That's why I
couldn't reproduce the autobuilder failure, it doesn't happen in my TZ.)

i.e. This causes a doc rebuild on my system (with freshly unpacked
source):
touch configure && ./configure && env TZ="US/Eastern" make -C doc

But this doesn't:
touch configure && ./configure && env TZ="Australia/Sydney" make -C doc

(So it's actually a bug in their build system, maybe they'd fix it
upstream? ;-))

Reviewed-by: Sam Bobroff <sam.bobroff@au1.ibm.com>

Cheers,
Sam.

> Fixes:
> 
>   http://autobuild.buildroot.net/results/3cbe65a46e75b8e67846d593884c96df97dec7a4
> 
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> ---
> Changes since v1: fix commit title
> 
> This is an alternative proposal to:
> 
>   https://patchwork.ozlabs.org/patch/724932/
> 
> and to:
> 
>   https://github.com/ntfreak/openocd/pull/4/commits/2c0cc66d5388e07679ac9f07c1ce0f8469931f02
> 
> which was submitted upstream but not accepted.
> ---
>  package/openocd/openocd.mk | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/package/openocd/openocd.mk b/package/openocd/openocd.mk
> index 21a302f..0d18365 100644
> --- a/package/openocd/openocd.mk
> +++ b/package/openocd/openocd.mk
> @@ -99,5 +99,20 @@ HOST_OPENOCD_CONF_OPTS = \
>  
>  HOST_OPENOCD_DEPENDENCIES = host-libftdi host-libusb host-libusb-compat
>  
> +# Avoid documentation rebuild. On PowerPC64(le), we patch the
> +# configure script. Due to this, the version.texi files gets
> +# regenerated, and then since it has a newer date than openocd.info,
> +# openocd build system rebuilds the documentation. Unfortunately, this
> +# documentation rebuild fails on old machines. We work around this by
> +# faking the date of the generated version.texi file, to make the
> +# build system believe the documentation doesn't need to be
> +# regenerated.
> +define OPENOCD_FIX_VERSION_TEXI
> +       touch -r $(@D)/doc/openocd.info $(@D)/doc/version.texi
> +endef
> +OPENOCD_POST_BUILD_HOOKS += OPENOCD_FIX_VERSION_TEXI
> +HOST_OPENOCD_POST_BUILD_HOOKS += OPENOCD_FIX_VERSION_TEXI
> +
> +
>  $(eval $(autotools-package))
>  $(eval $(host-autotools-package))
> -- 
> 2.7.4

>>>>> "Thomas" == Thomas Petazzoni <thomas.petazzoni@free-electrons.com> writes:

 > On PowerPC64(le), we patch all configure scripts. Due to this, the
 > version.texi in OpenOCD files gets regenerated, and then since it has
 > a newer date than openocd.info, openocd build system rebuilds the
 > documentation. Unfortunately, this documentation rebuild fails on old
 > machines.

 > We work around this by faking the date of the generated version.texi
 > file, to make the build system believe the documentation doesn't need
 > to be regenerated.

 > Fixes:

 >   http://autobuild.buildroot.net/results/3cbe65a46e75b8e67846d593884c96df97dec7a4

 > Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
 > ---
 > Changes since v1: fix commit title

Committed, thanks.

Hello,

On Tue, 28 Feb 2017 11:26:25 +1100, Sam Bobroff wrote:

> i.e. This causes a doc rebuild on my system (with freshly unpacked
> source):
> touch configure && ./configure && env TZ="US/Eastern" make -C doc
> 
> But this doesn't:
> touch configure && ./configure && env TZ="Australia/Sydney" make -C doc
> 
> (So it's actually a bug in their build system, maybe they'd fix it
> upstream? ;-))

I'm not sure it's really a bug.

The version.texi file contains a date, which will be 17 May 2015 or 18
May 2015 depending on your time zone.

In one case, the version.texi file generated will be the same as the
one in the tarball, and in this case, it is careful not to change the
timestamp. In other case, the version.texi file really has changed, and
therefore its timestamp is updated, causing the rebuild.

That's my explanation of the issue. Of course, there's always the
possibility that I did not fully understand the origin of the issue.

Best regards,

Thomas