Re: [PATCH] configure: actually disable 'git_update' mode with --disable-git-update

[Dan Streetman <ddstreet@canonical.com>]

On Tue, Sep 22, 2020 at 12:34 PM Daniel P. Berrangé <berrange@redhat.com> wrote:
>
> On Wed, Jul 29, 2020 at 03:58:29PM -0400, Dan Streetman wrote:
> > The --disable-git-update configure param sets git_update=no, but
> > some later checks only look for the .git dir. This changes the
> > --enable-git-update to set git_update=yes but also fail if it
> > does not find a .git dir. Then all the later checks for the .git
> > dir can just be changed to a check for $git_update = "yes".
> >
> > Also update the Makefile to skip the 'git_update' checks if it has
> > been disabled.
> >
> > This is needed because downstream packagers, e.g. Debian, Ubuntu, etc,
> > also keep the source code in git, but do not want to enable the
> > 'git_update' mode; with the current code, that's not possible even
> > if the downstream package specifies --disable-git-update.
>
> Lets recap the original intended behaviour
>
>  1. User building from master qemu.git or a fork
>      a) git_update=yes (default)
>          - Always sync submodules to required commit
>
>      b) git_update=no  (--disable-git-update)
>          - Never sync submodules, user is responsible for sync
>          - Validate submodules are at correct commit and fail if not.
>
>  2. User building from tarball
>      - Never do anything git related at all
>
>
> Your change is removing the validation from  1.b).

Would you accept adding a --disable-git-submodules-check so downstream
packagers can keep the source in git, but avoid the submodule
validation?
Or do you have another suggestion for handling this?

Michael, Christian, do you have any suggestions or preference for how
this should be handled in Debian and Ubuntu?

> This is not desirable
> in general, because if a user has done a git pull and failed to sync the
> submodules, they are liable to get obscure, hard to diagnose errors later
> in the build process. This puts a burden on the user and maintainers who
> have to waste time diagnosing such problems.

Yep, this problem causes the same obscure, hard to diagnose errors
later in the build with downstream packages, but only if the .git dir
is present, because the build process is subtly changed in that case.

>
>
>
> > Signed-off-by: Dan Streetman <ddstreet@canonical.com>
> > ---
> > Note this is a rebased resend of a previous email to qemu-trivial:
> > https://lists.nongnu.org/archive/html/qemu-trivial/2020-07/msg00180.html
>
> NB, I'm removing qemu-trivial, because I don't think this patch
> qualifies as trivial.
>
>
> >
> >  Makefile  | 15 +++++++++------
> >  configure | 21 +++++++++++++--------
> >  2 files changed, 22 insertions(+), 14 deletions(-)
> >
> > diff --git a/Makefile b/Makefile
> > index c2120d8d48..42550ae086 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -25,6 +25,8 @@ git-submodule-update:
> >
> >  .PHONY: git-submodule-update
> >
> > +# If --disable-git-update specified, skip these git checks
> > +ifneq (no,$(GIT_UPDATE))
> >  git_module_status := $(shell \
> >    cd '$(SRC_PATH)' && \
> >    GIT="$(GIT)" ./scripts/git-submodule.sh status $(GIT_SUBMODULES); \
> > @@ -32,7 +34,12 @@ git_module_status := $(shell \
> >  )
> >
> >  ifeq (1,$(git_module_status))
> > -ifeq (no,$(GIT_UPDATE))
> > +ifeq (yes,$(GIT_UPDATE))
> > +git-submodule-update:
> > +     $(call quiet-command, \
> > +          (cd $(SRC_PATH) && GIT="$(GIT)" ./scripts/git-submodule.sh update $(GIT_SUBMODULES)), \
> > +          "GIT","$(GIT_SUBMODULES)")
> > +else
> >  git-submodule-update:
> >       $(call quiet-command, \
> >              echo && \
> > @@ -41,11 +48,7 @@ git-submodule-update:
> >              echo "from the source directory checkout $(SRC_PATH)" && \
> >              echo && \
> >              exit 1)
> > -else
> > -git-submodule-update:
> > -     $(call quiet-command, \
> > -          (cd $(SRC_PATH) && GIT="$(GIT)" ./scripts/git-submodule.sh update $(GIT_SUBMODULES)), \
> > -          "GIT","$(GIT_SUBMODULES)")
> > +endif
> >  endif
> >  endif
> >
> > diff --git a/configure b/configure
> > index 2acc4d1465..e7a241e971 100755
> > --- a/configure
> > +++ b/configure
> > @@ -318,7 +318,7 @@ then
> >      git_submodules="$git_submodules tests/fp/berkeley-testfloat-3"
> >      git_submodules="$git_submodules tests/fp/berkeley-softfloat-3"
> >  else
> > -    git_update=no
> > +    git_update=""
> >      git_submodules=""
> >
> >      if ! test -f "$source_path/ui/keycodemapdb/README"
> > @@ -1598,7 +1598,12 @@ for opt do
> >    ;;
> >    --with-git=*) git="$optarg"
> >    ;;
> > -  --enable-git-update) git_update=yes
> > +  --enable-git-update)
> > +      git_update=yes
> > +      if test ! -e "$source_path/.git"; then
> > +          echo "ERROR: cannot --enable-git-update without .git"
> > +          exit 1
> > +      fi
> >    ;;
> >    --disable-git-update) git_update=no
> >    ;;
> > @@ -2011,7 +2016,7 @@ fi
> >  # Consult white-list to determine whether to enable werror
> >  # by default.  Only enable by default for git builds
> >  if test -z "$werror" ; then
> > -    if test -e "$source_path/.git" && \
> > +    if test "$git_update" = "yes" && \
> >          { test "$linux" = "yes" || test "$mingw32" = "yes"; }; then
> >          werror="yes"
> >      else
> > @@ -4412,10 +4417,10 @@ EOF
> >      fdt=system
> >    else
> >        # have GIT checkout, so activate dtc submodule
> > -      if test -e "${source_path}/.git" ; then
> > +      if test "$git_update" = "yes" ; then
> >            git_submodules="${git_submodules} dtc"
> >        fi
> > -      if test -d "${source_path}/dtc/libfdt" || test -e "${source_path}/.git" ; then
> > +      if test -d "${source_path}/dtc/libfdt" || test "$git_update" = "yes" ; then
> >            fdt=git
> >            mkdir -p dtc
> >            if [ "$pwd_is_source_path" != "y" ] ; then
> > @@ -5385,7 +5390,7 @@ case "$capstone" in
> >    "" | yes)
> >      if $pkg_config capstone; then
> >        capstone=system
> > -    elif test -e "${source_path}/.git" && test $git_update = 'yes' ; then
> > +    elif test "$git_update" = "yes" ; then
> >        capstone=git
> >      elif test -e "${source_path}/capstone/Makefile" ; then
> >        capstone=internal
> > @@ -6414,7 +6419,7 @@ case "$slirp" in
> >    "" | yes)
> >      if $pkg_config slirp; then
> >        slirp=system
> > -    elif test -e "${source_path}/.git" && test $git_update = 'yes' ; then
> > +    elif test "$git_update" = "yes" ; then
> >        slirp=git
> >      elif test -e "${source_path}/slirp/Makefile" ; then
> >        slirp=internal
> > @@ -6776,7 +6781,7 @@ if test "$cpu" = "s390x" ; then
> >      roms="$roms s390-ccw"
> >      # SLOF is required for building the s390-ccw firmware on s390x,
> >      # since it is using the libnet code from SLOF for network booting.
> > -    if test -e "${source_path}/.git" ; then
> > +    if test "$git_update" = "yes" ; then
> >        git_submodules="${git_submodules} roms/SLOF"
> >      fi
> >    fi
> > --
> > 2.25.1
> >
> >
>
> Regards,
> Daniel
> --
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>