can someone explain "git" versus "gitr" wrt PREFERRED_VERSION?

["Robert P. J. Day" <rpjday@crashcourse.ca>]

  possibly a stupid question but i've never let that stop me before.
still rummaging around in the bitbake user manual and looking through
the oe and poky codebase, and i notice examples like this (from poky).

  first, there's the recipe and PREFERRED_VERSION for drm:

meta/recipes-graphics/drm/libdrm_git.bb:
  SRCREV = "e01d68f9f3acfc35fe164283904b5d058c2ab378"
  PV = "2.4.40+git${SRCPV}"

meta-yocto/conf/distro/include/poky-floating-revisions.inc:
  #PREFERRED_VERSION_libdrm ?= "2.4.0+git${SRCREV}"

  also, the recipe and PFEFERRED_VERSION for libxcb:

meta/recipes-graphics/xorg-lib/libxcb_git.bb:
  SRCREV = "625ed596cae6dd8175aeb6cb6f26784928042f22"
  PV = "1.1.90.1+gitr${SRCPV}"

meta-yocto/conf/distro/include/poky-floating-revisions.inc:
  #PREFERRED_VERSION_libxcb ?= "1.1.90.1+gitr${SRCREV}"


  admittedly, the PREFERRED_VERSION settings for both of those are
commented out, but why does the first use:

  git${SRCREV}

while the second uses:

  gitr${SRCREV}

so what's with "git" versus "gitr"? i see no mention of this in the
bitbake user manual (would that be the right place to explain that?).
or is that covered in one of the higher-level yocto manuals?

  also (and i realize this is outside the scope of the bitbake
manual), i noticed the meta-oe layer adds another git-based version
selector in the gitpkgv.bbclass. is *that* documented anywhere? i
don't see a single mention of the phrase "gitpkgv" in any of the
current yocto docs.

  thoughts?

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
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