[pl-seminar] starting soon: seminar by Andreas Zeller

[Ben Liblit <liblit@xxxxxxxxxxx>]

Prof. Andreas Zeller's PL seminar talk will be starting soon!  Please 
join us at *11am* in room *2310 CS*:  <https://www.cs.wisc.edu/events/3628>.
*Abstract.* Knowing which part of a program processes which parts of an 
input can reveal the structure of the input as well as the structure of 
the program. In a URL "http://www.example.com/path/";, for instance, the 
protocol âhttp", the host âwww.example.com", and the path âpath" would 
be handled by different functions and stored in different variables. 
Given a set of sample inputs, we use _dynamic tainting_ to trace the 
data flow of each input character, and aggregate those input fragments 
that would be handled by the same function into lexical and syntactical 
entities. The result is a _context-free grammar_ that accurately 
reflects valid input structure; as it draws on function and variable 
names, it can be as readable as textbook examples:
	URL ::= PROTOCOL "://" HOST "/" PATH
	PROTOCOL ::= âhttpâ | âhttpsâ | â
	HOST ::= /[a-zA-Z0-9.]+/
	...

We expect inferred grammars to considerably ease the understanding of 
file and input formats. Their most important use, however, will be in 
automatic fuzz testing, where grammars can easily be turned into 
producers that help to quickly cover program features. Our grammar-based 
LANGFUZZ fuzzer is in daily use at Mozilla and has uncovered more than 
4,000 defects so far; mining grammars automatically will bring such 
techniques to a wide range of programs. For details on our work on 
grammar mining, see https://www.st.cs.uni-saarland.de/models/autogram/
*Bio.* Andreas Zeller is a full professor for Software Engineering at 
Saarland University in SaarbrÃcken, Germany, since 2001. His research 
concerns the analysis of large software systems and their development 
process. In 2010, Zeller was inducted as Fellow of the ACM for his 
contributions to automated debugging and mining software archives, for 
which he also was awarded 10-year impact awards from ACM SIGSOFT and 
ICSE. In 2011, he received an ERC Advanced Grant, Europe's highest and 
most prestigious individual research grant, for work on specification 
mining and test case generation. In 2013, Zeller co-founded Testfabrik 
AG, a start-up on automatic testing of Web applications, where he chairs 
the supervisory board.