Error in building documentation from source

[Joe Altman]

Greetings...
 
I've some sort of image error in building the docs from source. I've
copied it below, and wonder how it might be fixed? Sometimes, the
issue causes many runs of make in the directory
/usr/doc/en_US.ISO8859-1 before all errors are exhausted and other
times (like the most recent) only one or two errors occur.

*** Error code 1 (ignored)
===> articles/building-products (all)
/usr/local/bin/gs -q -dNOPAUSE -dBATCH -dSAFER -dDELAYSAFER
-sPAPERSIZE=letter
-r72 -sDEVICE=bbox  -sOutputFile=/dev/null  
/usr/doc/en_US.ISO8859-1/articles/building-products/../../../share/images/articles/building-products/freebsd-branches.ps
>
/usr/doc/en_US.ISO8859-1/articles/building-products/../../../share/images/articles/building-products/freebsd-branches.eps
2>&1
*** Error code 1

Stop in /usr/doc/en_US.ISO8859-1/articles/building-products.
*** Error code 1

Stop in /usr/doc/en_US.ISO8859-1/articles.
*** Error code 1

Stop in /usr/doc/en_US.ISO8859-1.

Followed by:

===> articles/building-products (all)
/usr/bin/perl /usr/doc/share/misc/epsgeom -offset 100 100 
/usr/doc/en_US.ISO8859-1/articles/building-products/../../../share/images/articles/building-products/freebsd-branches.eps
| /usr/local/bin/gs -q -dBATCH -dGraphicsAlphaBits=4 
-dTextAlphaBits=4  -dEPSCrop -r100x100  -dNOPAUSE -dSAFER -sDEVICE=pnm 
-sOutputFile=-  -g`/usr/bin/perl /usr/doc/share/misc/epsgeom -geom 100
100 
/usr/doc/en_US.ISO8859-1/articles/building-products/../../../share/images/articles/building-products/freebsd-branches.eps`
-  | /usr/local/bin/pnmtopng > 
/usr/doc/en_US.ISO8859-1/articles/building-products/../../../share/images/articles/building-products/freebsd-branches.png
Error: no BoundingBox found.
Error: no BoundingBox found.
pnmtopng: bad magic number - not a ppm, pgm, or pbm file
*** Error code 1

Stop in /usr/doc/en_US.ISO8859-1/articles/building-products.
*** Error code 1

Stop in /usr/doc/en_US.ISO8859-1/articles.
*** Error code 1

Stop in /usr/doc/en_US.ISO8859-1.

For both images in the
/usr/share/doc/en_US.ISO8859-1/articles/building-products/
directory, the result displayed in my browser is an image that
contains this text: 

The image "file:///usr/share/doc/en_US.ISO8859-1/articles/building-products/freebsd-branches.png"
cannot be displayed because it contains errors.

A similar condition exists for other image directories:

file:///usr/share/doc/en_US.ISO8859-1/books/handbook/geom/striping.png

All images in:
file:///usr/share/doc/en_US.ISO8859-1/books/handbook/security/
file:///usr/share/doc/en_US.ISO8859-1/books/handbook/vinum/
file:///usr/share/doc/en_US.ISO8859-1/articles/releng/

Unless someone here knows the fix, I think that a bug report should go
to the doc project mailing list; is that correct?

Regards,

Joe