documentation pdf build fail (HEAD)

Hello,

I build the pdf (for HEAD) almost daily without problems, but at the
moment I get the error below.

I am not sure whether to blame my particular setup (debian stretch), or
whether there might be an error in the .sgml. The html files still
build OK.

If anyone has a suggestion on how to tackle this I'd be grateful.

thanks,

Erik Rijkers

[...]
[INFO] FOUserAgent - Rendered page #526.
[INFO] FOUserAgent - Rendered page #527.
[INFO] FOUserAgent - Rendered page #528.
[INFO] FOUserAgent - Rendered page #529.
[[ERROR] FOP - Exception <org.apache.fop.apps.FOPException:
org.apache.fop.fo.ValidationException: The column-number or number of
cells in the row overflows the number of fo:table-columns specified for
the table. (See position 47337:52207)
javax.xml.transform.TransformerException:
org.apache.fop.fo.ValidationException: The column-number or number of
cells in the row overflows the number of fo:table-columns specified for
the table. (See position 47337:52207)>org.apache.fop.apps.FOPException:
org.apache.fop.fo.ValidationException: The column-number or number of
cells in the row overflows the number of fo:table-columns specified for
the table. (See position 47337:52207)
javax.xml.transform.TransformerException:
org.apache.fop.fo.ValidationException: The column-number or number of
cells in the row overflows the number of fo:table-columns specified for
the table. (See position 47337:52207)
at
org.apache.fop.cli.InputHandler.transformTo(InputHandler.java:289)
at
org.apache.fop.cli.InputHandler.renderTo(InputHandler.java:115)
at org.apache.fop.cli.Main.startFOP(Main.java:186)
at org.apache.fop.cli.Main.main(Main.java:217)
Caused by: javax.xml.transform.TransformerException:
org.apache.fop.fo.ValidationException: The column-number or number of
cells in the row overflows the number of fo:table-columns specified for
the table. (See position 47337:52207)
at
org.apache.xalan.transformer.TransformerIdentityImpl.transform(TransformerIdentityImpl.java:502)
at
org.apache.fop.cli.InputHandler.transformTo(InputHandler.java:286)
... 3 more
Caused by: org.apache.fop.fo.ValidationException: The column-number or
number of cells in the row overflows the number of fo:table-columns
specified for the table. (See position 47337:52207)
at
org.apache.fop.events.ValidationExceptionFactory.createException(ValidationExceptionFactory.java:38)
at
org.apache.fop.events.EventExceptionManager.throwException(EventExceptionManager.java:58)
at
org.apache.fop.events.DefaultEventBroadcaster$1.invoke(DefaultEventBroadcaster.java:175)
at com.sun.proxy.$Proxy4.tooManyCells(Unknown Source)
at
org.apache.fop.fo.flow.table.TableCellContainer.addTableCellChild(TableCellContainer.java:75)
at
org.apache.fop.fo.flow.table.TableRow.addChildNode(TableRow.java:95)
at
org.apache.fop.fo.FOTreeBuilder$MainFOHandler.startElement(FOTreeBuilder.java:324)
at
org.apache.fop.fo.FOTreeBuilder.startElement(FOTreeBuilder.java:179)
at
org.apache.xalan.transformer.TransformerIdentityImpl.startElement(TransformerIdentityImpl.java:1073)
at
org.apache.xerces.parsers.AbstractSAXParser.startElement(Unknown Source)
at
org.apache.xerces.xinclude.XIncludeHandler.startElement(Unknown Source)
at
org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanStartElement(Unknown
Source)
at
org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown
Source)
at
org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown
Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown
Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown
Source)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown
Source)
at
org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
at
org.apache.xalan.transformer.TransformerIdentityImpl.transform(TransformerIdentityImpl.java:485)
... 4 more