How to build docs from master?

Hi all.
 
I have installed PG (master) from git, but it seems the docs are not built
issuing "make install".
I've tried "make docs" but it fails with:
 
      interface Makefile:127: recipe for target 'HTML.index' failed
make[3]: *** [HTML.index] Error 1
make[3]: Leaving directory '/home/andreak/dev/postgresql/doc/src/sgml'
Makefile:8: recipe for target 'all' failed
make[2]: *** [all] Error 2
make[2]: Leaving directory '/home/andreak/dev/postgresql/doc/src'
Makefile:16: recipe for target 'all' failed
make[1]: *** [all] Error 2
make[1]: Leaving directory '/home/andreak/dev/postgresql/doc'
GNUmakefile:17: recipe for target 'docs' failed
make: *** [docs] Error 2
 
 
Any hints?
 
Thanks.

 
-- Andreas Joseph Krogh
CTO / Partner - Visena AS
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