This is pdfTeX, Version 3.14159265-2.6-1.40.18 (TeX Live 2017) (preloaded format=pdflatex 2019.1.9)  6 JUN 2019 15:32
entering extended mode
 restricted \write18 enabled.
 %&-line parsing enabled.
**Penrose19.tex

! Emergency stop.
<*> Penrose19.tex
                 
*** (job aborted, file error in nonstop mode)

 
Here is how much of TeX's memory you used:
 3 strings out of 493041
 104 string characters out of 6137191
 53127 words of memory out of 5000000
 3652 multiletter control sequences out of 15000+600000
 3640 words of font info for 14 fonts, out of 8000000 for 9000
 1137 hyphenation exceptions out of 8191
 0i,0n,0p,1b,6s stack positions out of 5000i,500n,10000p,200000b,80000s
!  ==> Fatal error occurred, no output PDF file produced!