Bug#1016321: boost1.74: FTBFS: runtime error: file /<>/tools/boostbook/xsl/annotation.xsl line 432 element element xsl:element: The effective name '' is not a valid QName.

[Andreas Beckmann]

There is also this error earlier in the logfile:

error: Problems running latex. Check your installation or look for typos 
in _formulas.tex and check _formulas.log!


Andreas