By setting 'buildroot' in .jhbuildrc so that jhbuild builds stuffs from outside git source trees, totem-pl-parser fails to build, with the following messages:

---8<---
libtool: link: ( cd ".libs" && rm -f "libtotem-plparser-mini.la" && ln -s "../libtotem-plparser-mini.la" "libtotem-plparser-mini.la" )
make[4]: *** No rule to make target `/home/thep/vcs/gnome_git/totem-pl-parser/plparse/totemplparser-marshal.c', needed by `TotemPlParser-1.0.gir'.  Stop.
make[4]: Leaving directory `/home/thep/build/gnome_git/totem-pl-parser/plparse'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/home/thep/build/gnome_git/totem-pl-parser/plparse'
make[2]: *** [all] Error 2
make[2]: Leaving directory `/home/thep/build/gnome_git/totem-pl-parser/plparse'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/thep/build/gnome_git/totem-pl-parser'
make: *** [all] Error 2
---8<---

It's this line that caused the problem:

> TotemPlParser_1_0_gir_FILES = $(addprefix $(srcdir)/,$(introspection_sources))

$(introspection_sources) includes some files generated in $(builddir), namely totemplparser-marshal.c and totem-pl-parser-features.h. And adding $(srcdir) prefix to them is just wrong.

Note that this kind of problem may not be caught by 'make distcheck', as the generated files are included in the distributed tarball. But this is not the case for VCS builds, such as with jhbuild.