Comment # 22 on bug 897284 from Johannes Meixner

FYI:

To verify whether or not a PostScript or EPS file needs any font,
use Ghostscript and watch its output about "Loading ... font".

For example in my case:
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$ gs -sDEVICE=nullpage -dBATCH -dNOPAUSE diagram.eps \
  | grep -o '^Loading .* font'

Loading NimbusRomNo9L-Regu font
Loading StandardSymL font
Loading NimbusRomNo9L-ReguItal font

$ gs -sDEVICE=nullpage -dBATCH -dNOPAUSE diagram.epswrite.eps \
  | grep -o '^Loading .* font'
[no output]
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