https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95385
Bug ID: 95385
Summary: GCC stop detect UBs after a divide by zero in for
statement
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: haoxintu at gmail dot com
Target Milestone: ---
This code test1.cc
#include<iostream>
int main () {
int a = 1;
for (int i = 0; i < 10; ++i) {
a /= i; // Error: division by zero on the first iteration
}
int b = 0;
int bb = 0 / b;
0 / 0;
std::cout << "ok" << std::endl;
return 0;
}
$./g++ -w -fsanitize=integer-divide-by-zero test1.cc ; ./a.out
test.cc:5:11: runtime error: division by zero
Floating point exception (core dumped)
GCC only detects one runtime error in for statement but leaves out detecting
the statements following ones.
In test2.cc
#include<iostream>
int main () {
/*
int a = 1;
for (int i = 0; i < 10; ++i) {
a /= i; // Error: division by zero on the first iteration
}
*/
int b = 0;
int bb = 0 / b;
0 / 0;
std::cout << "ok" << std::endl;
return 0;
}
$./g++ -w -fsanitize=integer-divide-by-zero test2.cc ; ./a.out
test.cc:11:16: runtime error: division by zero
test.cc:12:7: runtime error: division by zero
ok
Should the main function return from "return 0" rather than exit directly from
the for statement?
