DWARF Standard


HOME
SPECIFICATIONS
FAQ
ISSUES



180613.1 Andrew Cagney 0xffff in tables rendered with spaces Editorial Open Ron Brender


Section 7.5.3, pg 206

The PDF document, when viewed with evince and/or firefoxes 
builtin viewer, seems to have embedded spaces in some hex values.
For instance when trying to cut/pasting a value from a table tables,
some values copy ok while others contain spaces?

Table 7.3: Tag encodings, page 206:
     DW_TAG_lo_user                 0x4080
     DW_TAG_hi_user                 0x f f f f
Table 7.5: Attribute encodings, page 212:
     DW_AT_lo_user                  0x2000
     DW_AT_hi_user                  0x3 f f f

I suspect it is coming from:

\newcommand{\xffff}		{0x\hspace{1pt}f\hspace{2pt}f\hspace{2pt}f\hspace{2pt}f}

RESOLUTION

The scheme noted above for the hex value 0xffff (and similarly for 0xff, 0x3f and
0x3fff) came into use as a way to suppress the ligatures that were generated by
LaTeX for these values. The editor resorted to using horizontal space to disable
the ligatures because \/ and {} didn't work, nor did the DisableLigatures command
in the microtext package. Don't ask why...

As a result of this issue a different workaround has been devised that should avoid
the problem and still give satisfactory esthetics. For example, for 0xffff the new
command definition is

\newcommand{\xffff} {0x\texttt{ffff}}

This (and similarly for the other values) will be used in all future releases of the
document.

--
03/14/21 -- Updated


All logos and trademarks in this site are property of their respective owner.
The comments are property of their posters, all the rest © 2007-2021 by DWARF Standards Committee.