concern with pdebuild --pbuilder cowbuilder

[Patrice Duroux <duroux.patrice@orange.fr>]

Hi,

It seems that pdebuild somehow calls 'debian/rules' before going to the pbuilder
environment and so it fails as some build-deps are required to run this
'debian/rules' but not available in the call environment.
In my case it is 'debian/rules' that includes some .mk files that are provided
by the build-deps.
 
I just found the following lines in the pdebuild script that may be responsible
for this (not sure at all!):

$ grep -H -n -C 3 "rules" /usr/bin/pdebuild 
/usr/bin/pdebuild-86-    SOURCE_OPTIONS=$(get_source_options)
/usr/bin/pdebuild-87-    eval dpkg-source ${SOURCE_OPTIONS} --before-build .
/usr/bin/pdebuild-88-    if should_clean_source; then
/usr/bin/pdebuild:89:        "${BUILDSOURCEROOTCMD}" debian/rules clean
/usr/bin/pdebuild-90-    fi
/usr/bin/pdebuild-91-    eval dpkg-source ${SOURCE_OPTIONS} -b .
/usr/bin/pdebuild-92-    if ! [ "../${DSC}" -ef "${BUILDRESULT}/${DSC}" ]; then

Why such a step is not done inside the pbuilder environment if this is required?
Then is there a way to avoid such a step in my case?

Thanks,
Patrice