Have a large input that causes a failure
(e.g., a core dump) but this input is to
Example: gcc takes input and crashes!
Question: What is the smallest input
Developed by Andreas Zeller et al. Institute for Software Technology Institute for Software Technology
double mult(double z[], int n) { WHICH PART OF BUG.C CAUSES
double mult(double z[], int n) { CRASH?????
void copy(double to[], from[], int count) {
void copy(double to[], from[], int count) {
int main (.) { . return copy(y,x,SIZE);}
int main (.) { . return copy(y,x,SIZE);} Institute for Software Technology Institute for Software Technology t(double z[],int n){int
The resulting substring is substantially
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Testing function that takes a program
and tests whether it produces a failure.
There are three different outcomes of such a testing function:
test(x)
The test produces the failure (FAIL, 8)
The test produces indeterminate results
Delta Debugging Institute for Software Technology Institute for Software Technology
Given:
An input c‘ ⊆ c is said to be the global
A testing function test(x) mapping an input
minimum iff test(c‘) = 8 and there exists
no c‘‘ with |c‘‘|≤|c‘| where
An input c with test(c) = 8.
Goal: Search for a smaller c‘ ⊂ c so that
An input c‘ ⊆ c is said to be the local
minimum iff test(c‘) = 8 and there exists no c‘‘⊂ c‘ where test(c‘‘) = 8. Institute for Software Technology Institute for Software Technology Minimizing delta debugging algorithm
Input: Let test and c be given such that test(c)=8 and test(∅)=9 hold.
Output: A c‘ ⊆ c such that test(c‘)=8
An input c‘⊆ c is n-minimal iff test(c‘) =
8 and there exists no c‘‘⊂ c‘ with |c‘| -
|c‘‘| ≤ n where test(c‘‘) = 8. Institute for Software Technology Institute for Software Technology
ddmin2(c,n) = ddmin2(∆ ,2) if ∃i∈{1,.,n}: test(∆ )=8 ddmin2(∇ ,max(n-1,2)) ddmin2(c,min(|c|,2n)) else if n<|c| 4. DONE otherwise test(c)=8 and n≤|c|Institute for Software Technology Institute for Software Technology
ddmin returns a 1-minimal result.
The complexity of ddmin is O(|c|2).
In the best case the complexity of ddmin
test(x) = 8 iff “2“ ⊆ x ⊆ cInstitute for Software Technology Institute for Software Technology
test(x) = 8 iff “18“ ⊆ x ⊆ c
Not only for inputs of type STRING Extensions of ddmin can be used to
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REPUBBLICA ITALIANA In nome del popolo italiano Tribunale di Udine sezione civile Il Tribunale in composizione monocratica, in persona del dott. Andrea ZULIANI , ha pronunciato la seguente SENTENZA nella causa civile iscritta al n° 6846/10 R.A.C.C. promossa , con atto dicitazione notificato il 15.12.2010 cron. n° 23601 U .N.E.P. di Udine, da - (A) e (B), con i difensori
ANTIFUNGAL AGENTS Objectives : To learn the general classes of fungal infections To learn the subclassification of antifungal drugs To know the mechanism of action and basic uses for antifungal drugs Fungal infections (mycoses), though not as frequent as bacterial or viral infections, have nonetheless been increasing in incidence in the human population over the last 15 years or so, l
Have a large input that causes a failure
(e.g., a core dump) but this input is to
Example: gcc takes input and crashes!
Testing function that takes a program
and tests whether it produces a failure.
There are three different outcomes of such a testing function:
test(x)
ddmin2(c,n) =